Category: Infection

Problem

Cather-associated urinary tract infections (CAUTIs) are the main causes of secondary infection in the blood stream, making up around 76% of all UTIs, due to the wrong use of urinary catheter (Kuriyama et al., 2017). There are three types of catheters, as indicated by the World Health Organization [WHO]: indwelling, external, and short-term (2018). Indwellling which include urethral and subrapubic, external catheters recommended for men with severe cognitive impairment, and short-term catheters for use over a short duration of time, for example, after surgery. The duration of using urinary catheterization is the main determinant of developing CAUTI.

Setting

Urinary catheters are mainly used on bed-ridden patients; hence their presence is higher in intensive care units at 60% while the rest consists of other divisions. Based on the different types of urinary catheters, other than the ICU, it is evident that residential institutions and medical wards are places where one can find patients with CAUTIs. Urinary catheters are ideal for use during surgery or when one has urinary retention or a condition that requires an accurate attainment of urinary output (Hu et al., 2018). Nonetheless, individuals receiving home-base care and with the aforementioned conditions also warrant urinary catheter use.

Description

CAUTIs account for 34% of all health-care associated infections, as highlighted by Hu et al (2018). Hu et al. (2018) further indicate that these catheters tend to be inappropriately used on the elderly even when they do not have a medical indication. Taha et al. (2017) state that while urinary catheters are inserted for the wrong reasons, healthcare providers are not aware of the catheterization. Sequentially, there is prolonged use which is unnecessary and bound to have a negative effect on the health of a patient. 60% of the CAUTIs can be prevented in the correct guidelines are followed. As a result, there should be clear indications for the need of a urinary catheter which should be well-maintained and removed in a timely manner.

Effects

CAUTIs have negative implications on the social and economic aspects of a patients life along with their physical health. While it results in patient discomfort and serious comorbidities such as endocarditis, urinary tract trauma, and sepsis, 13, 000 deaths in the United States are due to UTIs acquired from healthcare (Letica-Kriegel et al., 2019; Wooller et al., 2018). These infections are comorbidities that arise as an individual receives care within a health facility and are not the main diagnosis. CAUTIs cause 13,000 estimated deaths yearly, increase the length of hospital stays by 2 to 4 days, and escalate healthcare costs for each individual by $1200 to $2400 (Taha et al., 2017). These effects sequentially affect ones quality of life negatively and drain an individuals as well as the societys resources.

Significance

The issue of CAUTIs is important to nursing because at least 69% of these infections can be avoided if the right measures are applied. Healthcare workers need to be educated on the appropriateness of urinary catheter use because wrong indications have been seen in an estimated 50% of indwelling catheters (Kuriyama et al., 2017; Safdar et al., 2016). Gaps in practice should be identified with the help of a multidisciplinary team periodically and training provided to healthcare workers to attain efficacy and efficiency in practice.

Solution

Collaboration among healthcare workers in different departments and on-job training are useful system interventions that could help ameliorate the problem. The implementation of a multidisciplinary team in a study by Taha et al. (2017) and an evidence-based paper by Pérez et al. (2017) yielded positive outcomes as the players are able to highlight issues within the system, leading to collective decision-making. Such a process is effective in resolving all of the issues bound to thwart the successful implementation of urinary catheter guidelines compared to a focus on a single department.

References

Hu, F. W., Shih, H. I., Hsu, H. C., Chen, C. H., & Chang, C. M. (2018). Dynamic changes in the appropriateness of urinary catheter use among hospitalized older patients in the emergency department. PloS One, 13(3). Web.

Kuriyama, A., Takada, T., Irie, H., Sakuraya, M., Katayama, K., Kawakami, D., Iwasaki, H., Fowler, K. E., Tokuda, Y., & Saint, S. (2017). Prevalence and appropriateness of urinary catheters in Japanese intensive care units: Results from a multicenter point prevalence study. Clinical Infectious Diseases, 64(suppl_2), S127S130. Web.

Letica-Kriegel, A. S., Salmasian, H., Vawdrey, D. K., Youngerman, B. E., Green, R. A., Furuya, E. Y., Calfee, D. P., & Perotte, R. (2019). Identifying the risk factors for catheter-associated urinary tract infections: a large cross-sectional study of six hospitals. BMJ Open, 9(2), e022137. Web.

Pérez, E., Uyan, B., Dzubay, D. P., & Fenton, S. H. (2017). Catheter-associated urinary tract infections: challenges and opportunities for the application of systems engineering. Health Systems, 6, 6876. Web.

Safdar, N., Codispoti, N., Purvis, S., & Knobloch, M. J. (2016). Patient perspectives on indwelling urinary catheter use in the hospital. American Journal of Infection Control, 44(3), e23e24. Web.

Taha, H., Raji, S. J., Khallaf, A., Abu Hija, S., Mathew, R., Rashed, H., Du Plessis, C., Allie, Z., & Ellahham, S. (2017). Improving catheter associated urinary tract infection rates in the medical units. BMJ Quality Improvement Reports, 6(1). Web.

Wooller, K. R., Backman, C., Gupta, S., Jennings, A., Hasimja-Saraqini, D., & Forster, A. J. (2018). A pre and post intervention study to reduce unnecessary urinary catheter use on general internal medicine wards of a large academic health science center. BMC health services research, 18(1), 642. Web.

World Health Organization [WHO]. (2018). Advanced infection prevention and control training: prevention of catheter-associated urinary tract infection (CAUTI): A student handbook. Web.

Effective infection prevention is one of the most pressing problems that emergency departments (ED) have to face. Since overcrowding is not a rare case in EDs, patients have to stay in close proximity to one another for a considerable period of time, which increases the risk of infection transmission. Acutely ill patients not only put the personnel and other patients at risk of catching the infections but can also acquire new diseases as their immune system is highly vulnerable.

Moreover, such a rapid-paced and complex clinical environment makes decision making and risk recognition highly challenging: in case of life-threatening issues, infection prevention can simply be overlooked, which will have substantial consequences for patients. The situation with elderly people is aggravated by the fact that their resistance to infections is low. It is highly important to provide such patients with personal protective equipment or to put them in isolation to protect from infections (Hallak et al., 2016).

The paper at hand is going to examine the use of isolation precautions compared to the application of PPE in male and female patents aged 70-90 being admitted to the ED in terms of their ability to affect the levels of hospital acquired infections within one month. It is postulated that isolation wards are more effective in preventing infections in elderly patients. The literature review encompassing five articles will attempt to prove this claim. The opposing viewpoint will also be considered to present a holistic picture of the issue.

Methods

Five peer-reviewed articles have been covered by the analysis. For this purpose, the search of academic databases (such as PubMed and Google Scholar) was conducted. The year of publication of the articles chosen for further consideration ranges from 2011 to 2016.

This is an important factor ensuring that the information is relevant. The keywords used for the search are directly related to the topic of the paper: e.g. hospital acquired infections, elderly patients, isolation precautions, personal protection equipment. Another criterion of choosing the articles was the study design: to ensure that the research will be multifaceted, both qualitative and quantitative studies were selected (2 and 3 articles respectively). Only two of the five articles use literature review as a method whereas three others present research results obtained by the authors (laboratory screenings and tests, statistical analysis, experiment), which allows claiming that the materials are not altogether secondary.

Review of Literature

Key Components of the Articles

In the study conducted by Hallak et al. (2016), the effectiveness of Ultrarapid PCR in combination with preemptive precautions is compared to traditional screening and isolation methods. The authors of the research analyzed a number of cases of infection for 15 months before any intervention was made. After that, they performed laboratory screening and tests in order to find out the results of applying Ultrarapid PCR and preemptive precautionary methods during one month.

The research proved high effectiveness of Ultrarapid PCR in conjunction with isolation, especially for high-risk patients. Such results are significant for the current paper as they not only allow seeing the statistics of isolation precautions in patients that run high risks of being infected but also reveal that the effectiveness of isolation implemented as the only measure is considerably lower than when it is applied in combination with modern methods.

Hinkin, Gammon, & Cutter (2013) attempted to evaluate the effectiveness of PPE in hospital settings in order to improve its application. For this purpose, they conducted an extensive search in CINAHL for studies on the subject of PPE and related terms, dated between 1995 and 2007. This allowed identifying all key types of PPE applied for infection prevention, estimate their impact, and dwell upon the ways to increase it. The authors of the study conclude that PPE is effective in infection control; however, they also admit that this effectiveness can be diminished owing to the lack of knowledge and compliance with standard PPE protocols. Compliance should be ensured by introducing related policies. The information obtained if valuable for the present research as PPE assessment is required to be able to compare it to isolation.

Avci, Ozgenc, Coskuner, & Olut (2012) did a research to identify how HAI affect elderly patients (over 65) compared to younger patients (below 65) in terms of frequency, outcome, type, and microbiological characteristics. They performed statistical analysis of 60585 using the T-test for numeric and Chi-square and Fishers test for exact variables. The results showed that HAI rate per 100 admissions was 1.95 for elderly and 1.05 for younger patients. To improve this situation, dedicated geriatric wards were recommended for the risk group. This article is especially valuable for the given research since it promotes isolation proposed by this study as an effective measure.

Adams, Johnson, & Lynch, (2011) studied the effects of pressure differentials on the containment of airborne pathogens and observed the impact produced by care provider movements on isolation effectiveness. They conducted an experiment releasing fluorescent microspheres into the test room with negative pressure, and studied the effects of changing pressure and movements of care providers on containment levels. It was found out that containment levels improved with increased negative pressure whereas increased movement from care providers diminished containment effectiveness. The researches recommended equipping all isolation wards with negative pressure apparatuses while decreasing needless movement. The article is helpful for this study as it presents an innovative way to improve effectiveness of an isolation ward.

Sprague, Reynolds, & Brindley (2016) questioned the benefits provided by isolation as there is too little evidence to make conclusions. Researchers reviewed literature for the last 25 years to single out various factors that involve the use of isolation, including effectiveness, costs, and psychological effects on patients. They also considered de-isolation as an alternative, which was admitted to be more advantageous in some cases. The article is necessary for this study as it provides an alternative and opposing view to the proposed intervention, which cannot be ignored before making final conclusions.

Comparison of the Articles

All the articles taken for the analysis are quite different in their focus, methods, and conclusions. Only two articles resorted to literature review as the major method of the study. However, the scope of the review is quite different: Hinkin et al. (2013) managed to analyze studies from 1995 to 2007 whereas Sprague et al. (2016) covered a longer period of 25 years, which makes their research more comprehensive and relevant. Besides, the focus of these studies is also different: the former is concerned with proving the effectiveness of PPE while the latter dwells upon ineffectiveness of isolation (Hinkin et al., 2013; Sprague et al., 2016).

The research by Avci et al. (2012) stands apart from all the others since the authors are the only ones to resort to statistical analysis. Moreover, this is the only research that touches upon the difference between infection risks in young and elderly patients (Avci et al., 2012). Like Hallak et al. (2016) and Adams et al. (2011), the researchers recommend using isolation ward as a preventive measure. Yet, the two latter articles have more in common than the rest. Both studies come to the conclusion that the effectiveness of an isolation ward can be increased if modern methods are applied in combination with it.

However, the methods they propose are different and include Ultra-rapid PCR and negative pressure apparatuses (Hallak et al., 2016; Adams et al., 2011). The research performed by Sprague et al. (2016) can be called the most controversial one as the position of the authors concerning isolation is rather vague. Still, they managed to indicate the major limitation of all the mentioned studies: the primary research on the topic is too scarce to be able to make definite conclusions. Another limitation is the time of the experiments (not exceeding one month of close supervision), which was too short to be positive about the effectiveness of the intervention. In addition, all the researchers took a one-sided perspective to prove their points and did not provide any alternatives to the proposed measure.

Areas of Further Study

There are ample opportunities to use isolation wards for prevention of the ED-associated infections. There is too little support of any particular method, which makes it reasonable to state that comparative studies in a variety of settings and populations are required to make conclusions (Hallak et al., 2016). The criteria to assess each area should include the percentage of prevented infections, the speed of the implementation, resources required to introduce the method, and obstacles that may arise in the process.

What is already known is that both PPE and isolation wards can be effective; however, the conditions under which one method is preferable over the other are unknown. Thus, the given research will rely upon the following thesis: Despite the fact that both PPE and isolation wards are currently applied for decreasing infection risks in elderly patients, the latter are still more effective, especially in combination with other interventions.

References

Adams, N. J., Johnson, D. L., & Lynch, R. A. (2011). The effect of pressure differential and care provider movement on airborne infectious isolation room containment effectiveness. American Journal of Infection Control, 39(2), 91-97.

Avci, M., Ozgenc, O., Coskuner, S. A., & Olut, A. I. (2012). Hospital acquired infections (HAI) in the elderly: Comparison with the younger patients. Archives of Gerontology and Geriatrics, 54(1), 247-250.

Hallak, G., Neuner, B., Schefold, J. C., Gorzelniak, K., Rapsch, B., Pfüller, R.,& Walter, M. (2016). Preemptive isolation precautions of patients at high risk for methicillin-resistant staphylococcus aureus in combination with Ultrarapid polymerase chain reaction screening as an effective tool for infection control. Infection Control & Hospital Epidemiology, 37(12), 1489-1491.

Hinkin, J., Gammon, J. H., & Cutter, J. (2013). Review of personal protection equipment used in practice. British Journal of Community Nursing, 13(1), 15-19.

Sprague, E., Reynolds, S., & Brindley, P. (2016). Patient isolation precautions: Are they worth it?. Canadian Respiratory Journal. Web.

Bloodstream infections take a tremendous toll on patients health and reduce their chances for recovery by a large margin, which is why the problem of CLABSI needs to be addressed in the clinical setting. Typically caused by intravascular devices, CLABSI represents a significant health concern, which is why the proposed idea of changing the healthcare staffs behaviors and attitudes toward workplace sanitation, particularly, hand hygiene, is vital (Maxfield, 2021). While introducing new standards for CLABSI prevention is crucial, these are the change in attitudes and the acceptance of responsibility that will help to minimize the threat of CLABSI.

Therefore, a balanced approach toward compliance and education appears to be quite reasonable. Indeed, while education is typically seen as the key prerogative of improving the management and prevention of CLABSI, increasing compliance with set guidelines is rarely regarded as a vital objective. Thus, paying attention to the specified aspect of CLABSI prevention seems to be a reasonable change to implement.

Additionally, it appears that the program aimed at reducing the threat of CLABSI would benefit from the inclusion of standardization approaches and the use of nurse leadership as the means of teaching staff members to avoid CLABSI in patients. While controlling compliance and education is admittedly important, the choice of a leadership model, which will define the efficacy of nurses learning, is also essential (Ingale et al., 2020).

Therefore, the use of the Transformational Leadership approach as the quickest way to introduce staff members to new information and change their attitudes toward workplace responsibility and acceptance of proposed guidelines is also indispensable (Moss et al., 2020). Once an appropriate leadership model is in place, nurses will be ready to accept a new range of responsibilities and tasks to avoid CLABSI in the hospital setting.

References

Ingale, S. A., More, M. V., & Shinde, M. (2020). Effectiveness of comprehensive nursing care towards prevention of catheter accompanying blood stream infection. Journal of Critical Reviews, 7(13), 93-96. Web.

Maxfield, M. D. (2021). Hematology/Oncology Unit champions promote care plans for CLABSI prevention. Mount St. Joseph University.

Moss, M., Ehni, J., Herbison, I., Rabii, K. B., Koepsell, C., Devries, E.,& Javaid, W. (2020). 505. Use of CLABSI prevention bundle audits to decrease CLABSI rates in COVID positive ICU patients in an acute care hospital in New York City during the COVID-19 epidemic. Open Forum Infectious Diseases, 7(Supplement_1), pp. S318-S319. Web.

The most common injuries that the athletes can meet with during the sports activities are the skin injuries. Nowadays, epidemics of bacterial infections that affect skin take place in amateur and professional sports teams more often. Some skin infections are non-hazardous and can be treated easily, but the others can represent a threat to an infected person’s life. The antibiotic-resistant skin infections are the dangerous ones, and they usually are characterized by the high-level morbidity and in some cases they can even lead to a fatal outcome. Thus, those infections need a special treatment and require the skills of the fast and correct recognition. Methicillin-resistant Staphylococcus aureus (MRSA) infection is one of the most prevalent in the sports environment, and according to the recent reports, nowadays it frequently requires hospitalization. Sports medicine specialists and physicians need to be aware of the new data related to skin injuries and infections in the athletic community to diagnose accurately, efficiently treat skin diseases, and prevent the infection outbreaks.

MRSA: Types, Symptoms, Treatments

MRSA is “an isolate of Staphylococcus aureus characterized by antibiotic resistance to penicillins and cephems, including methicillin, oxacillin, and other narrow spectrum β-lactamase resistant penicillin antibiotics” (Diduch et al. 557). MRSA can develop virulently, and in some particularly severe cases the hospitalization is required for a person diagnosed with MRSA. The several cases of death caused by the infection were reported. The potentiality of the fatal outcomes is taken seriously by the public, and currently MRSA infection research gains more attention.

Nowadays there are two types of MRSA recognized. In the recent past, MRSA was “traditionally viewed as a hospital pathogen,” but nowadays the infection is frequently met in the other communities, and particularly in group sports, such as football, volleyball, wrestling, rugby, etc. (Winterstein 189). Thus, MRSA can be hospital-associated (HA-MRSA) or community-associated (CA-MRSA). The HA-MRSA’s treatment always was problematic and had many issues. This kind of infection “affects primarily those in hospitals and nursing homes, those with immune disorders, and those with recent antibiotic usage” (Micheli 504). These requirements and conditions are not necessary for CA-MRSA, and it can affect even healthy people.

The threat of MRSA is in its virulence and the resistance to several antibiotics. CA-MRSA can be found in the skin lesions caused by many of the known infections, the damage from which is usually mild. “MRSA can be the pathogen involved in many skin conditions,” such as folliculitis, scabies, impetigo, furunculosis and others (Micheli 504). The neglecting of the symptoms and inappropriate treatment can cause the development of MRSA. The cases of the severe skin damage, necrotizing fasciitis and abscesses are often reported. “Fully invasive CA-MRSA is not common, but it can cause significant mortality and disabling outcomes” (Winterstein 189).

CA-MRSA infection can be recognized by skin lesions, “which can appear in a variety of ways including folliculitis, impetigo, mild to moderate cellulitis, large soft tissue abscesses measuring up to 7 cm in diameter, and can occur simultaneously on different areas of the body” (Diduch et al. 559). Sports medicine specialist need to pay attention to the fact that MRSA lesions often imitate other skin and soft tissue lesions. The systemic symptoms such as fever, vomiting, malaise, and nausea should be recognized timely.

The treatment of the infection usually includes the drainage of abscesses and usage of the oral antibiotics. Usually, the treatment procedures can be defined only after obtaining results of culture and antibiotic sensitivity analysis. Hospitalization and surgical treatment, and intravenous antibiotics are required in cases of severe lesions caused by infection. The appropriate treatment of skin and soft tissue lesions is determined by clinical presentation. The period of treatment usually lasts up to 14 days, but it depends directly on the severity of infection and the recovery process. The correct treatment of the individual cases helps to prevent the widespread dissemination of infection that can lead to an outbreak in the community.

The Impact of MRSA on Sports Activities and Professions

Like all the other diseases, skin infections interfere with the athletic activities and performance. Trainers and athletes need to pay a significant attention to any manifestations of skin infections in teams. Even the infections that are in fact do not affect the health severely, without the appropriate medical therapy can become infected with MRSA. In the case of MRSA infection, the diagnosis must be especially quick and correct because “once contracted by one athlete, the disease can transmit rapidly throughout the team,” and so the one athlete can infect the whole team and provoke the infection epidemic (Eaves 216). An athlete who was diagnosed with the symptoms of MRSA infection should be immediately withdrawn from all the sportive activities, and separated from the team members. The medical treatment must be provided for the infected individual. The athletes can return to practice only when the infection lesions are completely dried, the antibiotic treatment is accomplished, and no new lesions appear on his or her skin within 48 hours (Fincher and O’Connor 303).

Along with the individual cases of MRSA infection, the multiple cases of mass infections that occurred in the various US athletic teams since 2003 were reported by the Center for Disease Control and Prevention (Diduch et al. 558). The risk factors that could be responsible for the infection development were sharing the contaminated equipment and towels, skin traumas, and cosmetic shaving. According to the latest research, the main risk factors that cause MRSA infection development are the skin-to-kin contacts, contacts with the contaminated items, crowding, poor hygiene, and the disturbed skin integrity (Fincher and O’Connor 302). Thus, it is evident that the athletic teams are especially prone to the dissemination of infection because of the close and prolonged contacts that are inherent in the sports environment. According to recent reports, the continuance of contacts is crucial for contamination process. The infection is more often passed to the teammates rather than to the opponents in the athletic competitions, and it means that “the repetitive, close contact predisposes players to infection with CA-MRSA” (Diduch et al. 558).

It was proven by many researchers that MRSA is highly contagious. As it was observed, the contamination more often occurred through the physical contacts, and often it occurs on uncovered the parts of the body: elbows, forearms, and knees (Diduch et al. 558). Nevertheless, the areas covered with the clothes are also exposed to infection because of abrasions caused by shaving. Even the superficial abrasions, scratches or traumas make athletes prone to infection. Sharing of the personal athletic equipment and towels also provoke the infection transmitting.

The level of participation of the infected athlete in the sportive activities and competitions is usually determined individually and is dependent on the particular conditions. But it is important to keep the diagnose athlete out of the group and to stick to the safety precautions; otherwise the consequences may be serious.

The criteria that can cause disqualification due to skin disorders are defined by the National Collegiate Athletic Association. The document concerns wrestling because this sport has a “long history of dermatologic issues” (Eaves 216). The football players also meet the high risk of CA-MRSA contamination. According to the latest research the MRSA manifestations are the most common in the football environment, and most of the players are treated with the surgical drainage (Diduch et al. 558).

Since many infections can be transmitted by skin-to-skin contacts, the sportive group activities are at risk. The contamination factors include “exposure to infection, compromised skin integrity, and transmission via person-to-person or person-to-object contact” (Diduch et al. 558). As it can be observed, the infection development within the group of athletes is usually caused by ignorance and lack of compliance with the rules of personal hygiene, inappropriate treatment or the lack of recognition of the individual infections that later develop through the physical contacts.

To prevent CA-MRSA infection one needs to keep up to the rules of the personal hygiene. Athletes need to wash their hands thoroughly, especially before and after treating wounds. It is necessary to take showers after activities. The towels and other personal equipment shouldn’t be shared, and they must be kept clean. The athletes with wounds and lesions must be provided with the proper first aid treatment, and those with the suspicious lesions should be diagnosed. During the participation in athletic activities, even the smallest wounds must be covered (Fincher and O’Connor 302).

It is possible to assume that the risk of dissemination of all the skin infections and disorders can be reduced by proper cleaning of the training rooms, equipment, and facilities. The trainers and athletes must gain awareness of the infection impacts on the sportive performance. Thus, the proper education is required. Athletes must be told to report about abrasions to their coaches or physicians, and the coaches in their turn need must be trained to recognize the symptoms and signs of MRSA infection.

Conclusion

The treatment of MRSA infections is problematic because it is highly contagious and resistant to the variety of antibiotics. For few decades, the infection often occurs in the athletic communities. CA-MRSA commonly transmitted through physical contacts, the skin traumas also make the transmitting fast. Within the athletic teams, the cases of MRSA infection epidemic are frequent. Usually, the infection development happens because of the noncompliance with the rules of hygiene, the infection symptoms neglecting, and the incorrect treatment. To avoid the infection outbreaks, first of all, the personal hygiene rules must be followed, and the thorough cleaning of the training rooms must be provided. The trainers need to be more alert of the skin infection manifestations among the team members. All the skin lesions have to be treated, and in case if the athlete shows the symptoms of CA-MRSA, he or she must be immediately excluded from the team and participation in the sports activities until the complete health recovery. The timely infections recognition and their appropriate treatment support the reduction in the MRSA proliferation and epidemics.

Works Cited

Diduch, David, Terry Grindstaff, Joseph Hart, John MacKnight, Dilaawar Mistry, Daniel Redziniak, and Kimberly Turman. “Methicillin-resistant Staphylococcus Aureus (MRSA) in the Athlete.” International Journal of Sports Medicine 30 (2009): 557-562. Print.

Eaves, Ted. The Practical Guide to Athletic Training, London, UK: Jones and Bartlett Publishers, 2010. Print.

Fincher, Louise and Daniel O’Connor. Clinical Pathology for Athletic Trainers: Recognizing Systemic Disease. Thorofare, NJ: Slack Incorporated, 2008. Print.

Micheli, Lyle. Encyclopedia of Sports Medicine. London, UK: Sage Publications, 2010. Print.

Winterstein, Andrew. Athletic Training Student Primer: A Foundation for Success. Thorofare, NJ: Slack Incorporated, 2009. Print.

Salmonellosis is one of the most dangerous infections which exists in the modern world. Many people (especially infants and children) suffer from this infection every year. Eggs are the sources for the infection. Layer-hen breeding farms are created with the purpose to increase the level of eggs and fowl on the markets.

At the same time, the violation of different norms, regulations and laws may be harmful not only to the industry but to the whole society. The infection is identified after 4-7 hours of bad products consumption, and may be led to hospitalization.

The research shows that acute salmonellosis is a reason for death of 400 people every year (“Salmonella”). The main focus of the discussion is a risk assessment of Salmonella hazards on the layer-hen breeding farms from different perspectives, managers, regulatory agents and scientists.

Industry Manager’s Brief

The highest risk the managers may wait for is the occurrence of salmonella on the whole farm, when all the products are infected. The hazard analysis and critical control points (HACCP) are created with the purpose to help managers conduct that control.

The managers on the layer-hen breeding farms should conduct the following actions on the basis of HACCP: analyze hazards; identify critical control points; provide some preventive actions; monitor critical control points’ correct some procedures, if necessary; test the manufacturing to make sure it works properly and organize a work in such a way that the HACCP documentary is record-kept effectively (Swanger).

On the basis of the mentioned steps, the managers of the layer-hen breeding farms should test for salmonella poultry and identify whether the required norms are met, check whether the current food safety regulations are appropriate, highlight the risk, appoint those who are going to be responsible for monitoring the jeopardy, reduce it in case of occurring, and provide some changes to the manufacturing process if necessary.

The critical control points.

Managers should know that if Salmonella enterica is found in the waste areas of the farm, the whole area should be disinfected as well as the checking actions should be provided on the farm. The instances of Salmonella Enteritidis in trash show that problem has affected the whole production chain.

The isolation of the trash from the production may only the reduce problem rate, not eliminate it (Davies, Liebana and Breslin 234). The manager of the farm is legally responsible for the products he/she supplies the markets with, so he/she is responsible for the food safety.

Following the rules of production, managers still cannot protect their products from hazards of infection.

Still, there are three key legal obligations managers should provide to assure product safety, “assurance programs on farms, the rapid and sustained refrigeration of eggs from farm to consumer, and the education of consumers and food workers about the risks associated with pooling, handling, and consuming raw or undercooked eggs” (Braden 516).

To make the reduction of salmonellosis cases effective and productive, the managers should listen to the information provided by scientists and regulatory agencies. These two categories of institutions work on the reduction of Salmonella Enteritidis. Scientists work on the identification of the source of the problem.

The integration of the discoveries they make into manufacturing may save many layer-hen breeding farms from spending money on the elimination of the problem. The pieces of advice provided by the regulatory agencies should be used by managers as they give hints on how to protect the production chain from microbiological risk.

Thus, it should be stated that the managers on the layer-hen breeding farms are responsible for both the production chain and the elimination of the hazards which may occur. Scientists and regulatory advisers are people who are aimed at helping the managers to reduce, if not to eliminate absolutely, the instances of Salmonella Enteritidis in the manufacturing.

Table of risk management for the reasons of salmonella occurrence in eggs

If one wants to follow the critical control points when the food is considered to be safety and the salmonella hazards are eliminated, the following table should be considered (Food Safety and Inspection Service 710).

Table. Pasteurization requirements 1

Regulatory Adviser’s Brief

Dwelling upon the appropriate level of protection for the main microbiological risk connected with the Salmonella Enteritidis, it should be mentioned that it is a level of the protection considered to be safe and appropriate for inhabitants of the country.

Referencing to the case, both people and chickens should be protected. The main purpose of the regulatory brief is to check whether food safety objectives meet an appropriate level of protection, define whether there is an effective high priority management intervention available to manage the particular microbiological risk and evaluate the plan of the industry management.

Getting down to identification of the appropriate level of protection, it should be mentioned that there are two main institutions which should work in this direction, managers of the farms and people themselves. Managers are responsible for the products they create, so on the final stage of production they should pack the product and deliver it in such a way that no any bacteria can reach it.

It should be remembered that desiccation is not a threat for Salmonella enterica. Furthermore, cleaning and disinfection on the regular basis are not harmful for this infection as well. Thus, to approach the necessary level of the protection from Salmonella enteric on the microbiological level, the farmers and managers should conduct some additional control devoted to these specific bacteria.

There is a risk that infected parents will contaminate other generations. The level of protection should be really high as the ability of the bacteria to resist to different outside influences sometimes frustrates (Pedersen, Olsen and Bisgaard 421).

To support the idea of food safety protection, the regulation was created to monitor the protection actions in the relation to the Salmonella Enteritidis. Regulation EC 1177/2003 states, (1) Salmonella should not be controlled by antimicrobials, and (2) mandatory vaccination should be provided in the countries where the infection spread is more than 10%.

Commission Regulation (EC) No. 1168/2006 identifies the terms for testing flocks in rear, (1) on the first day (the day of the chicken delivery from the hatchery) and (2) two weeks prior to entering laying phase (Carrique-Mas and Davies 2).

Furthermore, there are a lot of different agencies which follow the process and can influence it by means of different regulations. These agencies are state, local, and federal health departments (“PulseNet”).

The main objective of food safety regulation is to assure the citizens of the country that the products they consume are clean and safe. At the same time, it is impossible to protect people if they do not follow some specific rules for personal maintenance. Appropriate hygiene and food keeping in accordance with the norms are the main rules for food safety.

So authors say that “reduction of intestinal colonization of Salmonella enterica during the grow-out period is crucial to provide safer eggs, minimize economic losses, and reduce the spread of human salmonellosis” (Kassaify and Mine 753).

It is possible to follow all the regulations mentioned above. Furthermore, it is even profitable for the manager, as in case of violation of the norms and the infection incidents occurrence, high fines should be set on him/her.

Scientific Advisor’s Brief

The main purpose of this brief is to provide the reader with the scientific hazard characteristics of the Salmonella enterica occurrence in eggs and other items produced on layer-hen breeding farms. Referencing to the risk management table, the following information may be provided. Wildlife species influence the rate of poultry infected with Salmonella enterica.

The molecular research conducted in the sphere shows that farms should be protected from rats, flies, litter, foxes and some other wild species (Liebana, et al 1028). The hazard to infection widespread may be caused by the age of the hen.

Scientists proved that the age influences the rate of Salmonella introduction via egg shell penetration (Messens, Grijspeerdt, and Herman 694). The understanding of this penetration and age influence may improve the quality of antivirus activities provided by managers and regulators.

It goes without saying that the ovaries and the oviducts are the main places for bacteria colonization. Thus, eggs are infected and it is impossible to identify which one is safe and which one is not. The vaccination is one of the best ways to reduce the hazard of the problem. The research proved that inoculations may be helpful if provided in time and if the necessary prescriptions were followed (Withanage 586).

It is possible to state that egg-packaging plants are also responsible for the contamination of the products. The failure to follow some specific norms of storage and packing is a great hazard to the products from the point of view of Salmonella appearance.

Davies, Liebana and Breslin also stated that wastes may be extremely dangerous if there are Salmonella bacteria there. The cleaning should be provided not only of the trash that was considered, but of the whole poultry on the farm (234).

The hazard may lie in human carelessness and imprudence. Dirty hands, raw products and uncooked dishes are the sources for Salmonella occurrence (Braden 516). There are specific norms which should be followed in relation to temperature and time of cooking. A failure to follow those norms may be a great hazard for consumers. The combination of all those hazards is dangerous for human life.

The high concentration of salmonella bacteria in the may also lead to the health problems. The infection is identified after 4-7 hours of bad products consumption, and may be led to hospitalization. The research shows that acute salmonellosis is a reason for death of 400 people every year (“Salmonella”).

Thus, coming out of the information mentioned above it may be stated that the main hazard for Salmonella is the violation of different norms and regulations.

If the farm follows all the regulations, makes the cleaning and disinfection operations in time and uses hazard analysis and critical control points for checking the bacteria presence in the products, it may be sure that all the actions are provided to reduce the possibility of infection occurrence. In addition, the scientific pieces of advice should be considered.

They mostly search for the sources of Salmonella and try to warn the managers on the layer-hen breeding farms against the threads. If the industry managers follow those pieces of advice it may reduce the costs on cleaning and inoculations in the future. Furthermore, the outbreaks of the salmonellosis in the society may be reduced to minimum, if not absolutely eliminated.

Works Cited

Braden, Christopher R. “Salmonella enterica Serotype Enteritidis and Eggs: A National Epidemic in the United States.” Clinical Infectious Diseases 43.4 (2006): 512-517. Print.

Carrique-Mas, Juan J. and Rhodri H. Davies. “Salmonella Enteritidis in commercial layer flocks in Europe: Legislative background, on farm sampling and main challenges.” Brazilian Journal of Poultry Science 10.1 (2008): 1-9. Print.

Davies, Robert, Liebana, Ernesto, and Mark Breslin. “Investigation of the distribution and control of Salmonella enterica serovar Enteritidis PT6 in layer breeding and egg production.” Avian Pathology: Journal of the W.V.P.A 32.3 (2003): 225-237. Print.

“Food Safety and Inspection Service, Department Of Agriculture.” 9 CFR – Code of Federal Regulations. Web.

Kassaify, Z. G. and Y. Mine. “Effect of Food Protein Supplements on Salmonella enteritidis Infection and Prevention in Laying Hens.” Poultry Science 83 (2004): 753–760. Print.

Liebana, E, et al. “Molecular fingerprinting evidence of the contribution of wildlife vectors in the maintenance of Salmonella Enteritidis infection in layer farms.” Journal of Applied Microbiology 94.6 (2003): 1024-1029. Print.

Messens, W., Grijspeerdt, K., and L. Herman. “Eggshell characteristics and penetration by Salmonella enterica serovar Enteritidis through the production period of a layer flock.” British Poultry Science 46.6 (2005): 694-700. Print.

Pedersen, Tina Broennum, Olsen, John Elmerdahl, and Magne Bisgaard. “Persistence of Salmonella Senftenberg in poultry production environments and investigation of its resistance to desiccation.” Avian Pathology 37.4 (2008): 421-427. Print.

“PulseNet.” Centers for Disease Control and Prevention. 28 Apr. 2009. Web.

“Salmonella.” Centers for Disease Control and Prevention. 27 Sept. 2010. Web.

Swanger, Nancy “HACCP (hazard analysis of critical control points).” International Encyclopedia of Hospitality Management. 2005. Web.

Withanage, G. S. K., et al. “Increased lymphocyte subpopulations and macrophages in the ovaries and oviducts of laying hens infected with Salmonella enterica serovar Enteritidis.” Avian Pathology 32.6 (2003): 583-590. Print.

Introduction

Background

Respiratory tract infections (RTIs) are common viral and bacterial infections that affect the lungs, throat, sinuses, and airways. The identification of these pathogens is necessary for specific and effective treatment of RTIs [1]. Usually, the identification of pathogenic organisms is cumbersome as they are harmful and adherence to strict precautionary steps in handling and confirming their identity is required. Equipment used in handling pathogens ought to be sterilised to avoid contaminating surfaces and exposing people to the risk of infections [1, 2]. Together with proper sterilisation procedures, wearing appropriate protective clothing is a precautionary measure that effectively reduces the risk of exposure to pathogens.

As microorganisms are pervasive, they are always interacting with humans and become part of everyday life. From this viewpoint, it is important to identity microorganisms for their profiles are critical in ascertaining their impact on humans, other animals, and the environment [2]. Ample evidence shows that bacteria are pathogens that can cause serious diseases amongst humans and animals, while others are important because they are used in beneficial production systems such as fermentation. The process of identifying unknown bacteria normally starts with their morphological features, followed by staining, biochemical reactions, and susceptibility tests. Genome sequencing is an advanced method that can be applied as a confirmatory test. In general, the bacterial nomenclature has no basis on genetic relatedness but on physical traits and metabolic aspects [2, 3], which comprise a set of unique traits making it possible to differentiate between bacteria.

Significant Infections of the Respiratory Tract

RTIs refer to infections affecting both the lower and upper respiratory tract. Comparatively, the upper RTIs are less pathogenic than the lower RTIs. Numerous RTIs-related deaths occur due to infections of the lower respiratory tract. Common infections of the lower respiratory tract include bronchitis, influenza, and pneumonia [4, 5]. Evidence shows pneumonia as the most common and serious form of RTIs despite the fact that influenza affects both the upper and lower respiratory tracts.

Normally, RTIs that affect the throat, sinuses, lungs, and airways occur due to viral infections and, to some extent, bacterial infections too. In humans, children are more susceptible to RTIs because their immune system is weaker than that of adults [1]. Nonetheless, the elderly are also prone to RTIs due to their advanced age [2]. It is, therefore, important to have a comprehensive understanding of RTIs because these infections spread in a variety of ways. Airborne matter bearing the viruses or bacteria has the capability of travelling far and spreading infections to large numbers of people. Direct and indirect contact with contaminated surfaces also contributes to the spread of the infections [2]. Proper hygiene practices are encouraged to minimise the proliferation and spread of RTIs. The use of a handkerchief in covering the nose and mouth during sneezing is one of the simplest ways of decreasing airborne and contact spread of microorganisms in sputum.

Though most RTIs subside without any treatment, taking painkillers, drinking plenty of water, and having ample rest effectively relieve symptoms. Antibiotics are discouraged unless a causative organism of RTIs has been established [1]. Since prevention is more appropriate than treatment, the observation of good hygiene is effective in avoiding and controlling the spread of RTIs [2]. However, in case the RTIs are serious, one ought to take over-the-counter medications such as antibiotics or painkillers. Otherwise, symptoms of RTIs mostly ease off after one to two weeks without the use of medication.

Microbiological Investigations on the Elderly

Generally, medical-related tests provide an accurate diagnosis of RTIs and offer reliable methods of drawing conclusions. Respiratory diseases among the old are among the main causes of morbidity and mortality. These tests are important among the old because symptoms can overlap due to viral and bacterial pathogens and cause inaccurate diagnosis and prognosis [2, 3]. Subsequently, opportunistic infections take advantage of RTIs and complicate their diagnosis and treatment. RTIs are prevalent among the elderly due to the existence of chronic conditions and deterioration of health. The elderly have underlying medical conditions that be complicated by infections such as RTIs. In addition, the deterioration of health with age reduces the immunity and increases the risk of bacterial or viral infections.

Benefits of Investigating the Respiratory Tract

RTIs are deadly infections to vulnerable groups, especially children and the elderly. Tests to establish the integrity of the respiratory system are important in ensuring the health of these vulnerable groups. The expectation is that specimens collected from the elderly have viral or bacterial pathogens [2], which have the potential of causing RTIs. Since RTIs are common, people often seek medications and most of the time they take medications without diagnosing their conditions. Acute sinusitis and bronchitis are some of the most common cases of RTIs that contribute to the abuse of antibiotics [3]. The general recommendations are that people should visit a physician when they present symptoms of RTIs, particularly when they appear serious. It is important for people, especially the elderly, with pre-existing medical conditions such as heart disease, diabetes, lung or kidney conditions, or on steroid medication, to seek medication even with the slightest signs of RTIs [2, 4]. Therefore, one should not overlook the symptoms of RTIs under such conditions since the mildest form of the condition can have detrimental effects.

The aim of the laboratory report was to explore the basic tests that form the foundation of microbiological methods employed in identifying unknown bacteria species. The tests revolve around a clinical sample obtained from an elderly person in intensive care. The patient seems to have underlying factors that have worsened his health condition. To understand the nature of RTIs, the specimen was tested to identify pathogenic microbes that are responsible for the condition. Tests indicated opportunistic infections that exploited the weak immune system of the elderly under investigation.

Materials and Methods

The sputum specimen (coded 7) was gram stained on horse blood agar (HBA), chocolate agar (CHA), and MacConkey agar (MCA), and then it was incubated for 24 hours at 37⁰C. The identification process started with the observation of lactose fermentation [3] on the MacConkey media. Biochemical tests such as catalase and oxidase reactions were done following Mosby’s Manual of Diagnostic and Laboratory Tests [6]. The catalase test ascertained the organism’s ability to carry out a reduction reaction that led to the colour change and production of gas. MacConkey agar was used to establish fastidiousness of the organism.

Subsequently, the nitrate reduction test and growth on nutrient agar (NA) at 42⁰C tests were done, according to the protocol in Textbook of Diagnostic Microbiology [7], and then used to identify the organism in this test. Susceptibility tests were done according to the protocol in Susceptibility Methods: Dilution and Disk Diffusion Methods [8] on Mueller Hinton Agar (MHA). The antibiotics used included Gentamicin, Ciprofloxacin, Imipenem, and Ceftazidime. The bacterium was cultured on plates containing each of the antibiotics and the inhibited region was observed. The responses of bacteria in terms of growth were recorded as either sensitive or not.

Results

The gram staining results revealed the presence of gram-negative bacilli and polymorphs. However, the bacteria were visible as rod-shaped bacteria in the MacConkey growth media. On the other hand, the HBA and CHA media had large and heavy growths as the colonies had metallic sheens and the characteristic smell of Pseudomonas. Though the MCA media had good growth, no lactose fermentation was observed.

Table 1: Summary of Biochemical Tests on Specimen 7.

Legend: (+) positive test (-) negative test.

Biochemical tests (Table 1) indicate the presence of gram-negative bacilli that was either Pseudomonas or Vibrio. The nitrate reduction test was positive for there was gas production. After zinc was added, the absence of a red/pink colour change was positive for nitrate reduction. The growth at 42⁰C on nutrient agar was positive with dense growth observed. The susceptibility test indicated fluorescent pigment visible on the MHA agar. Figure 1 shows the workflow that led to the identification of RTIs in the sputum.

Table 2: Susceptibility Test Results.

Legend: S = sensitive.

Therefore, the susceptibility test confirms that the organism was Pseudomonas aerugenosa.

Discussion

MacConkey Agar is a selective growth medium exclusively used for detecting gram-negative bacteria. MacConkey Agar has been formulated to suppress the growth of gram-positive bacteria. When Specimen 7 was streaked on the media, rod-shaped microorganisms were seen on MacConkey [3]. Further, MacConkey has both selective and differential properties where the bacteria ferment mannitol and release acidic by-products that either promote or inhibit further growth of the bacteria, as the acidic concentrations build up. Although the organism was incapable of fermenting mannitol, growth on the MacConkey agar was indicative of the presence of fastidious gram-negative bacteria in the specimen.

HBA is for the cultivation of non-fastidious and fastidious microorganisms with the indication that haemolysis took place in the bacterial cultures. Chocolate agar is non-selective, enriched, and crucial for the isolation of pathogenic organisms. The media is appropriate for culturing fastidious respiratory organisms. The growth characteristics observed in Specimen 7 meets the criteria for respiratory bacteria [6, 7]. HBA is a nonspecific media, which does not distinguish between gram-negative and gram-positive organisms. A selective media for either kind of bacteria would have indicated if organisms in the specimen were gram-negative or gram-positive [5]. Whereas CHA confirmed the organism to be fastidious, HBA revealed it as a non-electrolytic one. The varying levels of specificities in these two media proved important in distinguishing microorganisms in the sputum and pinpointing the pathogenic one as Pseudomonas. Vibrio carries out haemolytic reactions on HBA but not Pseudomonas.

As the bacteria produced catalase that broke down hydrogen peroxide [9], the organism was sensitive to antibiotics in all the susceptibility tests done. Other biochemical tests, such as the oxidase test, were positive and exhibited a colour change. In the test, the presence of cytochrome oxidase in bacteria was ascertained. The enzyme facilitates the transportation of electrons between donors and a redox component, tetramethyl-p-phenylene diamine dihydrochloride, which is reduced to a deep purple colour [9, 10]. The organism being studied produces catalase and is oxidative (Table 1). These two tests are characteristic of Pseudomonas and Vibrio organisms that are mostly screened using this procedure.

A nitrate test determines the ability of organisms to reduce nitrate (NO₃) to nitrite (NO₂). This reaction is dependent on the production of a nitrate reductase enzyme by the organism [6]. The nitrate reduction test was positive with the production of gas. After zinc was added, the absence of a red/pink colour change was positive for nitrate reduction. In this case, the colour change did not occur for there was no reduction of nitrate. The enzyme had already performed denitrification, leading to the formation of ammonia or nitrogen. Thus, the test confirmed the presence of aerugenosa in the specimen.

The specimen colour (light green mucoid sputum) was indicative of the presence of aerugenosa. In part, the sample was obtained from an elderly man in the intensive care unit with pneumonia. Literature indicates that the bacterium is a common cause of gram-negative infections in patients who have a weak immune system, such as the old and hospitalised patients [1, 9, 10, and 11]. The medical conditions of the patient are therefore suggestive of Pseudomonas but not Vibrio.

Antibiotic susceptibility tests done involved the use of Gentamicin CN10, Ciprofloxacin CIP5, Imipenem IMP10, and Ceftazidime CAZ30 to determine the organism’s effectiveness. The testing on organism treatment options followed the Kirby-Bauer method [9]. The minimum and maximum zones of inhibition were recorded at 18 and 38 for Gentamicin and Ciprofloxacin, respectively (Table 2). The sensitivity test proved that Ciprofloxacin had the minimum effect against the organism, whereas Gentamicin had the maximum inhibitory effect, and hence a suitable drug against the organism.

The bacterium, aeruginosa, causes infections that have been considered a great threat due to the high mortality rate recorded for both pneumonia and bacteraemia conditions. Recently, the organism has developed resistance to antibacterial drugs. The bacteria have been documented to be highly adaptable because of its big genome [1, 9]. The adaptation has made the bacteria to be a multi-drug resistance (MDR) organism [10]. The elderly are prone to pseudomonal infection because of underlying factors such as diabetes, lung diseases, and the presence of invasive devices. Age is also a considerable factor that has increased the occurrence of MDR organisms [10, 11]. Such predisposing health conditions compromise the immune system and render the elderly vulnerable to opportunistic diseases and microorganisms. The rule of the thumb is to undertake comprehensive medical exams on elderly patients to establish their vulnerabilities.

The symptoms associated with aerugenosa infection in the bloodstream include malaise, chills, body aches, faintness, nausea, diarrhoea, and declined urination [1, 10]. In the case of pneumonia, symptoms include fever and chills, difficulty in breathing, cough and bloody mucus that can be yellow or green. The incubation period of the bacteria is usually between 24 and 72 hours. The complications associated with the infection are life-threatening and range from compromising the host immune system, with constant pneumonia attacks, urinary tract infections, and bacteraemia [10]. Perhaps the greatest challenge with monitoring and evaluating RTIs is their overlapping symptoms with other medical conditions. Normally, lack of adequate medical skills to diagnose and the existence of overlapping medical conditions make patients overlook or take a long time before seeking medical services. Studies have found that most people prefer to take easily dispensable medication for conditions that might be more serious [1, 9, and 11]. The development of multi-drug resistance in most pathogens perhaps arises from the patients’ use of antibiotics in an unwarranted manner.

As an opportunistic pathogen, aeruginosa exists in healthy individuals without necessarily causing harm. Pathogenesis of this bacterium is dependent on a complex group of factors because of its toxigenic and invasive attributes. The bacterium attaches to a surface and colonises it [1, 10], causing infection at the point of attachment [9, 10], then multiplies and spreads in the bloodstream, causing systemic infection [11]. Elucidation of the infection mechanism shows that attachment on the cell surface is crucial for systemic infection to occur. The attachment step increases virulence at one point before the pathogen spreads to the rest of the body through the bloodstream.

Although aerugenosa is increasingly becoming resistant to drugs, a combination of drugs is effective in minimising its effects on the host [10]. Evidence shows that a combination of penicillin and aminoglycoside are effective in the elimination of the bacterium [9, 10, and 11]. For antimicrobial susceptibility tests, results indicated that Gentamicin is the most effective and specific for aerugenosa [9]. The use of a two-drug regimen is subject to physician’s advice. The use of a combination of beta-lactams and aminoglycosides such as gentamicin, amikacin, and tobramycin are desirable for patients who have been on a single drug regimen.

References

Jones C, Valeig S, Sova R, Weiss C. Inside-out ultraviolet-c sterilisation of Pseudomonas aeruginosa biofilm in vitro. Photochem Photobiol. 2016; 92(6): 835-841.

Jain S, Self WH, Wunderink RG, Fakhran S, Balk R, Bramley AM, et al. Community-acquired pneumonia requiring hospitalization among US adults. N Engl J Med. 2015; 373(5): 415-427.

Tille P. Bailey & Scott’s diagnostic microbiology. 14th ed. St. Louis, MO: Elsevier Health Sciences; 2015.

Reed KD. Respiratory tract infections: a clinical approach. In: Tang, Y, Sussman M, Liu D, Poxton I, Schwartzman J, editors. Molecular medical microbiology. 2nd ed. London: Academic Press; 2014. p. 1499-1506.

Kenny SL, Shaw TD, Downey DG, Moore JE, Rendall JC, Elborn JS. Eradication of Pseudomonas aeruginosa in adults with cystic fibrosis. BMJ Open Resp Res. 2014; 1(e000021): 1-7.

Pagana KD, Pagana TJ. Mosby’s manual of diagnostic and laboratory tests. 6th ed. New York, NY: Elsevier Health Sciences; 2017.

Mahon CR, Mahon R. Textbook of diagnostic microbiology. 5th ed. New York, NY: Elsevier Health Sciences; 2014.

Jorgensen JH, Turnidge JD. Susceptibility test methods: dilution and disk diffusion methods. In: Jorgensen J, Pfaller M, Carroll K, Funke G, Landry M, Richter S, et al., editors. Manual of clinical microbiology, 11th ed. Washington, WA: ASM Press; 2015. p. 1253-1273.

Garge S, Azimi S, Diggle SP. A simple mung bean infection model for studying the virulence of Pseudomonas aeruginosa. BioRXIV. 2017; 1(229757): 1-6.

Potron A, Poirel L, Nordmann P. Emerging broad-spectrum resistance in Pseudomonas aeruginosa and Acinetobacter baumannii: mechanisms and epidemiology. Int J Antimicrob Agents. 2015; 45(6): 568-585.

Streeter K, Katouli M. Pseudomonas aeruginosa: a review of their pathogenesis and prevalence in clinical settings and the environment. Infect Epidemiol Microbiol. 2016; 2(1): 25-32.

Abstract

The main purpose of this experiment was to identify organisms that cause infection of the urinary tract and to prescribe effective antibiotics that the organism could not resistant. The selected methods in this experiment include Gram stain, spot test, biochemical testing, sensitive plate set up, reading biochemical testing and reading sensitive plate set up. The results of the experiment indicate presence of pathogens responsible for urinary tract infection mainly staphylococcus aureus as well asserting the patient’s sensibility certain antibiotics. These antibiotics included Flucloxicillin Fox 10, Vancomycin Va 5, PencillinP.05 and Clindamycin.

Aim

The aim of this experiment is to identify the pathogen responsible for Urinary Tract Infection in the patient and to prescribe suitable medication for the condition. Standard microbiology techniques will be employed to establish the most appropriate measure to address the patient’s condition.

Introduction

According to Mayo Clinic Staff (2010), urinary tract infection starts in the urinary system. The Kidneys, bladder and urethra form the urinary system. This system can become infected, but most infections involve the bladder and the urethra, which form the lower urinary system. Microbiologists can confirm a urinary tract infection by testing a patient’s tissue sample to identify the microorganism responsible.

This experiment will employ some tests including agar streaking and differential split agar plate, which isolates and differentiate the bacteria responsible for urinary tract infection (Friedman et al. 1991). Strain testing that involves performing biochemical testing and colony morphology and gram stain to identify responsible organism (Mortensen 2009). Antibiotic sensitivity testing that includes setting up of sensitivity plates (Dennis Guttmann 1963).These tests are done to ascertain the degree of sensitivity or resistance of organism isolated from patient’s tissue sample to an appropriate variety of antibiotic drugs.

Method

The first test conducted was the Gram stain test. A single drop of saline was dropped onto a slide, after which a single colony was selected and immersified in saline then spread over the 1.5-centimeter slide. The slide was air dried, then heated and finally allowed to cool. Three to four drops of 1% crystal violet was added to the smear and left to stand for 30 seconds. Before the smear could dry, it was rinsed with distilled water and Gram’s iodine added. After 30 seconds, it was rinsed with 95% ethanol until the run-off was colorless. Safranin, was added and left to stand for 30 seconds. The slide was dried by gently blotting it on paper towel. It was examined under a compound microscope using 100X oil immersion objective to identify individual microorganisms.

Two biochemical tests were conducted to validate bacterial identification. First, was the test to validate oxidase positive bacteria, where an oxidase strip was touched to a loopful of bacteria. The other test was the microbact 12A strip, where a bacterial suspension was made by picking 1 to 3 isolated colonies from culture plate re-suspended in 2.5 milliliters of sterile saline. After opening the microbsct strip, 4 drops of bacterial suspension were added to each of the 12 wells. Three wells( 1,2,3) were overlaid with mineral oil using a sterile Pasteur pipette, resealed and incubated for 24 hours. After the 24 hours, 2 drops of Indole reagent was added to the eighth well and evaluated within 2 minutes. In well 10, 1 drop each of VPI and VPII reagent were added and evaluated after 15 minutes. In well 12, 1 drop of TDA reagent was added and results recorded immediately. The reaction in each well was recorded as either positive or negative by comparing to a color chart.

For the Sensitivity plate setup, nutrient agar plate was divided into 4 sections. Using a sterile swab, a single colony was transferred into a 2.5 milliliters sterile bottle. It was mixed gently but thoroughly and poured over the entire plate then allowed to dry for 15 minutes. A different antibiotic disk was placed into each quadrant using forceps. The plates were sealed with parafilm, inverted and incubated for 24 hours for later observation.

Results

Specimen used was from the wound of the patient and several tests ran. As recorded in the figure below (i), Colony morphology test turned grey and many small colonies were observed. They were circular in shape with a flat margin elevation. The mannitol salt test revealed a yellow coloring while the gram test turned purple an indication of positive result. Bergey et al. (1994) outline gram stain as the separation of all bacteria into either primary dye, which is gram-positive or secondary dye, which is gram-negative. In this test, when the bacteria was treated with iodine they assumed the crystal violet in their thick layer of peptidoglycan. The catalase test produced bubbles and the coagulae test showed positive revealing the presence of the suspected organism.

Figure i. Results of the wound swab tests.

Figure ii. Results of the antibiotic sensitivity tests.

The sensitivity test was done on four antibiotics. Flucloxicillin Fox 10 and Clindamycin did not show sensitivity as indicated in figure (ii).penicilin showed no results as the antibiotic disk was moved away. The only sensitive antibiotic was Vancomycin Va 5.

Discussion

This practical was to identify microorganisms that are responsible for the urinary tract infection in the patient and to establish suitable remedy for the condition using antibiotics. The gram stain test revealed existence of staphylococcus- aureous. The specimen showed sensitivity to antibiotics.

Using the microbact 12A system to identify the pathogenic bacteria, a positive reaction in glucose and mannitol tests, but a negative reaction in Xylose test indicates the presence of Staphylococcus species, which live in areas of high salt concentration.

Oxidase test shows organisms that secretes cytochrome oxiase enzyme. Cytochrome oxidase is involved in an electron movement link as it transfers electrons to oxygen from donor molecule. Oxydase reagent possesses a chromogenic agent, a compound that when oxidized, changes color.The reagent turns blue within 15 seconds if the organism tested produces cytochrome oxidase. It is a test used to determine if an organism cytochrome oxidase (MacFaddin (ed.) 2000).

References

Allen, ME 2010, ‘MacConkey Agar Plates Protocols’, American Society for Microbiology.

Bergey, D, Holt, JG, Krieg, N & Sneath, P 1994, Bergey’s Manual of Determinative Bacteriology, 9th edn, Lippincott Williams & Wilkins.

Beveridge, T & Davies, JA 1983, ‘Cellular responses of Bacillus subtilis and Escherichia coli to the Gram stain’, Journal of bacteriology , p. 156.

Dennis Guttmann 1963, ‘Diagnosis of Urinary infection:Comparison of a Pour-Plate Counting Method with a Routine Method’, British Journal of Medicine.

Friedman, MP, Danielski, JM, Day, T, Dunne, J, Evangelista, A & Freeman, T 1991, ‘Rapid Isolation and Presumptive Diagnosis of Uropathogens by Using Membrane Filtration and Differential Media’, JOURNAL of Clinical Microbiology, vol 29, no. 11, p. 2385.

MacFaddin, J (ed.) 2000, ‘Biochemical Tests for Identification of Medical Bacteria’, 3rd edn, Lippincott Williams and Wilkins, Philadelphia.

Mayo Clinic Staff 2010, Urinary tract infection, Web.

Mortensen, N 2009, ‘STUDIES IN URINARY TRACT INFECTIONS:Biochemical Characteristics of Coagulase-negative Staphylococci Associated with Urinary Tract Infections’, Journal of Internal Medicine, vol 186, no. 6.

Swenson, JM, Facklam, RR & Thornsberry, C 1990, ‘Antimicrobial susceptibility of vancomycin-resistant Leuconostoc, Pediococcus and Lactobacillus species’, in Antimicrob Agents Chemother.

Abstract

Bloodborne infections are infectious ailments that can be transmitted from one person to another through contact with infected blood or body fluids. Human immunodeficiency virus (HIV) is a common example of a blood-borne disorder that is a public health concern globally. HIV is a retrovirus that attacks white blood cells, particularly CD4 cells, thereby lowering the body’s capacity to fight infections.

The disease is spread through unprotected sexual encounters with infected people, mother-to-child transmission, sharing of needles among drug users, transfusion with contaminated blood, or transplants with infected organs. The major symptoms of HIV infection include fever, headaches, muscle pain, and swollen lymph nodes. These symptoms are characteristic of a process known as seroconversion when the body reacts to the virus. The diagnosis of HIV infections involves the detection of antibodies in the blood. There is no cure for this bloodborne infection. However, patient compliance with antiretroviral therapy is helpful and can help infected people to live healthy, productive lives.

Introduction

A bloodborne infection can be defined as a contagious disorder that is disseminated through making contact with contaminated blood. Body fluids may also be responsible for the spread of bloodborne infections. Common examples of bloodborne infections include hepatitis B, Human immunodeficiency virus (HIV), hepatitis C, and viral hemorrhagic fevers such as Marburg, Ebola, and yellow fever, and Lassa (Fernando, 2018). The purpose of this paper is to discuss the HIV virus as an example of bloodborne infection. The mode of spread, symptoms, diagnosis, treatment, and prevention of the disease are also explained.

The HIV Virus

HIV is a virus that attacks the immune system and changes it, thereby leading to increased susceptibility to other infections. The disease may proceed to an advanced state known as Acquired Immunodeficiency Syndrome (AIDS) if the infected person does not undergo treatment. It takes approximately 10 to 15 years for an untreated, infected person to develop AIDS (Maartens, Celum, & Lewin, 2014). HIV targets specific cells of the immune system known as CD4 cells, which are part of T-helper cells. The purpose of T cells is to identify aberrant cells and infecting microorganisms. Therefore, HIV infection hampers the functioning of these cells and predisposes the affected person to opportunistic infections.

HIV is a ribonucleic acid (RNA) virus belonging to a family known as retroviruses. The genes of retroviruses are encoded in RNA instead of deoxyribonucleic acid (DNA). When retroviruses attack the host cell, they inject a copy of their genome into the new cell and alter its genome (Mailler et al., 2016). Reverse transcriptase, which is an enzyme that converts RNA to DNA, is then used to change the viral RNA to DNA. The new viral DNA is then integrated into the host DNA. As a result, the virus can multiply within the cell. Therefore, the life cycle of the HIV virus is grouped into seven key phases: binding, fusion, reverse transcription, integration, replication, assembly, and budding as shown in Figure 1 (U. S. Department of Health and Human Services, 2018).

In the binding phase, the virus attaches to a CD4 cell through gp41 and gp120 proteins that are found on the viral surface (Mailler et al., 2016). In the fusion stage, the virus is absorbed into the cell following attachment to the CD4 cell. During this process, the external coat of the virus is lost, leaving behind the capsid containing HIV RNA and three important enzymes. Reverse transcriptase then converts the single-stranded viral RNA into double-stranded DNA to match the human DNA in the cell in the reverse transcription stage.

Integration happens when the newly synthesized DNA virus traverses the nuclear membrane of the CD4 cells to reach the central nucleus where it is incorporated into the human DNA. The altered CD4 nucleus now receives instructions from the virus to produce raw materials for more new viruses. The assemblage of a new virus entails cutting up and joining of the viral particles, which is mediated by the enzyme protease. The newly formed virus leaves the cell by a process known as budding and infects new CD4 cells, which begins a new cycle. The old CD4 cell then dies. This process continues until most of the CD4 cells are destroyed.

Mode of Spread of the Infection

HIV is spread when mucous membrane or injured tissue of a healthy person make contact with blood, semen, breast milk, pre-seminal fluid, vaginal, and rectal fluids from an infected person (Joly, Odloak, & Rondó, 2016). Areas of the body that contain mucous membranes include the inner lining of the mouth, vagina, rectum, and opening of the penis. Infection may also occur when these fluids are introduced directly into the bloodstream through injection (Vun et al., 2016).

The most common method of HIV infection is unprotected sexual intercourse (anal or vaginal) with an infected person. Injection drug users who share needles can transmit the infection among themselves. Blood transfusions with infected blood or organ transplants can also spread HIV. However, the likelihood of contracting HIV through this method is minimal due to stringent measures taken to screen blood and organs before transfusions and transplants respectively.

HIV-positive mothers can spread the disease to their babies in the course of gestation, during childbirth, or breastfeeding in what is referred to as mother-to-child transmission. Healthcare workers can also get infected through unintentional contact with contaminated fluids through injuries from infected sharps or handling body fluids from infected patients (Rice, Tomkins, & Ncube, 2015). Contrary to misinformed myths and perceptions, one cannot contract HIV from hugging, handshakes, or a closed-mouth kiss with an infected person. In addition, sharing items such as utensils, toilet seats, and doorknobs cannot spread HIV.

Epidemiology

HIV is among the leading public health challenges all over the world. UNAIDS statistics show that approximately 36.9 million people all over the world were HIV-positive in 2017. Out of this number, 1.8 million were children below the age of 15. About 5000 new HIV infections per day occurred in 2017, bringing the total number of infected to 1.8 million people. It is also estimated that 10% of these new infections occurred in children under 15 years through breastfeeding, pregnancy, or childbirth.

About 75% of the infected people were aware of their status, whereas the remaining 25% still required access to HIV-testing services. In the same year, nearly 940,000 people succumbed to HIV-related infections globally, which was a significant reduction from 1.4 million in 2010 and 1.9 million in 2004 (Global Statistics, 2018).

The prevalence of HIV is higher in low- and middle-income countries compared to developing countries. For example, the 2017 statistics show that 53% of the global HIV infections were reported in eastern and southern regions of Africa, whereas 16% of the contagions were observed in central and western Africa (Global Statistics, 2018). On the other hand, 14% of the infections were reported in Asia, whereas only 6% were noted in Europe and America.

HIV infections affect not only individual health but also the well-being of households and communities. The disease is linked to negative economic growth. Furthermore, other public health problems such as food insecurity and other infectious diseases are also rampant in countries with high HIV infections (Global Statistics, 2018).

Symptoms

The symptoms of HIV differ from one person to another. However, most people often experience flu-like signs in the first few days following infection. These symptoms are attributed to the body’s response to the virus in a process known as seroconversion (Lin, Gianella, Tenenbaum, Little, & Hoenigl, 2017). Specific indications include fever, fatigue, sore throat, headache, joint pain, muscle aches, and enlarged lymph nodes. When these symptoms appear, the virus has gained access into the bloodstream and began multiplying. Therefore, the body reacts by mounting an immune response. Fatigue is also evident in later stages of HIV infection.

The function of lymph nodes is to protect the body by ridding it of infectious bacteria and viruses. Therefore, lymph nodes become inflamed when there is an infection. Rashes may also develop in the form of pinkish breakouts or itchy boils.

Gastrointestinal disturbances such as queasiness, vomiting, and diarrhea may also be experienced in the advanced stages of HIV infection. Unrelenting dry coughs that are not relieved by antibiotics or inhalers can be experienced in HIV patients with severe infections. Night sweats can also be experienced in the early and later stages of HIV even in cool temperatures. Since HIV presents with a wide array of unspecific symptoms that may be observed in other illnesses, it is necessary to get tested.

Diagnosis

The diagnosis of HIV infection involves testing blood for the presence of antibodies specific to the HIV1 or HIV2 virus, which the body usually develops to ward off infections. However, it may take between 6 weeks and 3 months for the body to develop HIV antibodies. This period is known as the window period. An individual in the window period may still pass on the virus to other people. Enzyme-linked immunosorbent assay (ELISA) is an antibody test that is used to diagnose HIV. However, the test may not be very accurate in the initial stages of infection before the body mounts a proper antibody response. Positive ELISA tests should be Western blotting. Saliva tests can also be used to diagnose the disease. Nonetheless, positive saliva tests need to be confirmed by blood tests.

After diagnosing HIV infection, it is important for the patient to undergo viral load testing to quantify the amount of virus in the bloodstream. A viral load test can also be used to diagnose early infection. Furthermore, the efficacy of treatment can be monitored by viral load findings. Three main techniques used to measure HIV viral load are branched DNA, reverse transcription-polymerase chain reaction, and nucleic acid sequence-based amplification assay (Gullett & Nolte, 2015). The three tests use the same basic principles where HIV is identified using DNA sequences that are complementary to those in the virus.

Treatment

No cure is available for HIV. However, various treatment methods can be used to prevent the multiplication of the virus thus boosting the immunity of the infected person. These drugs are referred to as antiretroviral therapy (ART). Different drugs can be used to target specific phases of the HIV life cycle. For example, HIV drugs that block the binding of the virus to CD4 receptors are referred to as entry inhibitors.

The reverse transcription stage can be blocked by two different reverse transcriptase inhibitors: nucleoside/tide and non-nucleoside (Rai, Pannek, & Fichtenbaum, 2018). On the other hand, medications that impede the viral integration process are referred to as integrase inhibitors, whereas the production of new viruses by assembling different components is blocked by protease inhibitors. Budding inhibitors block the exit of the new HIV virus from the old CD4 cells while maturation inhibitors impede the last assembly process.

Current recommendations show that HIV treatment should commence at the time of diagnosis to lower the probability of sickness and death by up to 57% (Poorolajal, Hooshmand, Mahjub, Esmailnasab, & Jenabi, 2016). Initiating treatment when CD4 cell count has dropped to 350 cells per milliliter increases adverse effects and reduces the survival period. Timely treatment maintains immunity by preserving the CD4 cells and minimizes the likelihood of transmitting the infection through low viral loads.

Prevention

Preventing HIV infection can be achieved by targeting each mode of infection. For example, couples are advised to avoid risky sexual behavior by getting tested and knowing each other’s HIV status. Consistent and correct condom use is also recommended with each sexual encounter for people who do not know each other’s HIV status, particularly commercial sex workers and men who have sex with other men. Limiting the number of sexual partners is also important to minimize the likelihood of contracting HIV.

Abstinence from injecting drugs also lowers the risk of becoming infected with HIV. However, drug users should use only sterile injections and avoid sharing them. Sexually transmitted infections (STIs) increase the likelihood of getting HIV because of damaged mucous membranes (Pelligrino, Zaitzow, Sothern, Scribner, & Phillippi, 2017). Therefore, testing and getting treated for STIs is necessary to prevent HIV infection.

Currently, pre-exposure prophylaxis (PrEP) is available for individuals who are HIV-negative but perceive themselves to be at risk of HIV infection. PrEP entails taking a drug called Truvada, which is a combination of two medications, every day (Straub, Berger, & Cruz, 2017). The presence of the PrEP medication in the bloodstream prevents the development of infection in the event that a person is exposed to the virus. PrEP is recommended for discordant couples, people who engage in risky sexual behavior, or injection drug users who share needles. PrEP has been shown to reduce the risk of HIV infection by 90% through sexual intercourse and by 70% through injection use (Dimitrov, Mâsse, & Donnell, 2016).

Conversely, post-exposure prophylaxis (PEP) is a prevention regimen that is administered to people following potential exposure to HIV. It may be given to someone who has had unprotected intercourse with an infected person or healthcare workers who may have been inadvertently exposed to HIV at work. For PEP to be effective, it should be taken within the first 3 days of exposure and continued for 4 weeks (Maartens et al., 2014).

HIV-positive mothers can protect their babies from the virus by attending antenatal clinics during pregnancy. The prevention of mother-to-child transmission entails giving specific drugs to pregnant women all through pregnancy as well as the newborn babies for 4 to 6 weeks (Cohn, Whitehouse, Tuttle, Lueck, & Tran, 2016). The medications prevent the development of infection in case the baby contracted the virus during childbirth.

Conclusion

HIV is a deadly bloodborne infection that is marked by immunosuppression. There is no cure for the disease, but infected people can stay healthy for a long time through antiretroviral therapy. On the other hand, new HIV infections can be prevented by taking adequate precautions that are specific to each mode of infection.

References

Cohn, J., Whitehouse, K., Tuttle, J., Lueck, K., & Tran, T. (2016). Pediatric HIV testing beyond the context of prevention of mother-to-child transmission: A systematic review and meta-analysis. The Lancet HIV, 3(10), e473-e481.

Dimitrov, D. T., Mâsse, B. R., & Donnell, D. (2016). PrEP adherence patterns strongly impact individual HIV risk and observed efficacy in randomized clinical trials. Journal of Acquired Immune Deficiency Syndromes (1999), 72(4), 444-451.

Fernando, D. (2018). The AIDS pandemic: Searching for a global response. Journal of the Association of Nurses in AIDS Care, 29(5), 635-641.

Global Statistics. (2018). Web.

Gullett, J. C., & Nolte, F. S. (2015). Quantitative nucleic acid amplification methods for viral infections. Clinical Chemistry, 61(1), 72-78.

Joly, M., Odloak, D., & Rondó, P. H. (2016). Human immunomodulation and initial HIV spread. Computers & Chemical Engineering, 84, 255-280.

Lin, T. C., Gianella, S., Tenenbaum, T., Little, S. J., & Hoenigl, M. (2017). A simple symptom score for acute human immunodeficiency virus infection in a San Diego community-based screening program. Clinical Infectious Diseases, 67(1), 105-111.

Maartens, G., Celum, C., & Lewin, S. R. (2014). HIV infection: Epidemiology, pathogenesis, treatment, and prevention. The Lancet, 384(9939), 258-271.

Mailler, E., Bernacchi, S., Marquet, R., Paillart, J. C., Vivet-Boudou, V., & Smyth, R. (2016). The life-cycle of the HIV-1 Gag–RNA complex. Viruses, 8(9), 1-19.

Pelligrino, N., Zaitzow, B. H., Sothern, M., Scribner, R., & Phillippi, S. (2017). Incarcerated black women in the Southern USA: A narrative review of STI and HIV risk and implications for future public health research, practice, and policy. Journal of Racial and Ethnic Health Disparities, 4(1), 9-18.

Poorolajal, J., Hooshmand, E., Mahjub, H., Esmailnasab, N., & Jenabi, E. (2016). Survival rate of AIDS disease and mortality in HIV-infected patients: A meta-analysis. Public Health, 139, 3-12.

Rai, M. A., Pannek, S., & Fichtenbaum, C. J. (2018). Emerging reverse transcriptase inhibitors for HIV-1 infection. Expert Opinion on Emerging Drugs, 23(2), 149-157.

Rice, B. D., Tomkins, S. E., & Ncube, F. M. (2015). Sharp truth: Health care workers remain at risk of bloodborne infection. Occupational Medicine, 65(3), 210-214.

Straub, D. M., Berger, T., & Cruz, F. (2017). Truvada as pre-exposure prophylaxis (Prep): One site’s clinical experiences. Journal of Adolescent Health, 60(2), S81-S82.

U. S. Department of Health and Human Services. (2018). Life cycle. Web.

Vun, M. C., Galang, R. R., Fujita, M., Killam, W., Gokhale, R., Pitman, J.,… Rouet, F. (2016). Cluster of HIV infections attributed to unsafe injection practices—Cambodia, December 1, 2014–February 28, 2015. MMWR Morbidity Mortality Weekly Report, 65(6), 142-145.

Introduction

Background

Pseudomonas aeruginosa, a gram-negative bacteria, is a significant cause of nosocomial infections among immuno-compromised patients. Wounds, abdomen, urinary tract, and respiratory tracts are primary sites of P. aeruginosa, leading to bacteraemia, which is a systemic infection of the bloodstream.¹ However, since P. aeruginosa is infectious, it can cause bacteraemia among immuno-competent individuals. Pseudomonal infection is life-threatening because the bacteria is resistant to most antibiotics, causes sepsis, and triggers the occurrence of septic shock in individuals.² Consequently, P. aeruginosa has a poor prognosis and exhibit mortality rates of between 26-39%, which is higher than that of related gram-negative pathogens.¹ In this view, medical researchers have focused on understanding the mechanism of pathogenesis to prevent and manage the occurrence of bacteraemia due to P. aeruginosa.

Justification

The study of the progression of infection caused P. aeruginosa to bacteraemia is essential because it provides additional information that is critical in elucidating the mechanism of pathogenesis. As one of the nosocomial infections in healthcare settings, P. aeruginosa threatens the lives of patients and contribute significantly to their comorbidities.³ Healthcare providers experience the challenges of treating nosocomial infections associated with P. aeruginosa due to their ability to colonise infection sites, penetrate tissues, and resist most antibiotics. Patients with severe burns are susceptible to bacteraemia because they have low immunity and burn sites that allow pathogens to colonise and penetrate their blood easily.⁴ As reliable animal models, mice allow effective monitoring of P. aeruginosa and its progression to bacteraemia in immuno-suppressed mice.

Statement of Research Question and Hypotheses

The study seeks to establish how health status and immune response varies following infection of healthy and immune-compromised mice by P. aeruginosa. The hypothesis of the study is that P. aeruginosa infection decreases health status as indicated by the loss of body weight and diminishes immune response among immuno-suppressed mice.

Methods

Data Collection

The experiment was set up to examine the influence of bacteraemia on body weight and leukocyte production on normal and immuno-compromised mice. Ten healthy mice (N = 10) were selected and randomly assigned to control group (n = 5) and test group (n = 5). At the commencement of the experiment, mice in the test group were treated with cyclophosphamide (CY) at the dosage of 200mg/kg to subdue their immunity. In contrast, mice in the control group were not given any treatment for their immune system to function normally. On day 0, mice in both the control and test groups were infected with P. aeruginosa through subcutaneous injection. For nine consecutive days of the experiment, the body weight was measured in grams as an indicator of the health status of mice. The blood sample of each mouse was obtained daily during the first six days, and the level of the immune response was assessed using the number of white blood cells produced in millions per millilitre.

Data Analysis

Descriptive statistics were used to explore data and establish patterns of central tendency and dispersion of body weight and leukocytes level in blood. Preliminary analysis requires the use of descriptive statistics because they provide a meaningful statistical summary that enhances understanding of raw data.⁵ Specifically, means and standard deviations provided critical information for interpreting variations in body weight and leukocytes level in successive days of the study. Subsequently, means of both body weight and the level of leukocytes were depicted in a clustered graph using lines and bars. The clustered graph with secondary scale was used because body weight and the level of leukocytes have different measures. T-test was also used to determine if the apparent differences in body weight and the level of leukocytes were statistically significant.

Results

Graph

The body weight of mice in both the test and control groups remained almost the same for the first four days. However, the means of body weight of CY mice declined gradually during the fourth day to the ninth day from about 26 grams to 20 grams, but that of control mice were relatively constant. Regarding the immune response, mice in both control and test groups exhibited the same level of leukocytes during the first three days. Comparatively, while the level of leukocytes rapidly diminished in CY mice, it increased to about 100 during the fourth day but stagnated at about 60 million white cells per millilitre of blood. Figure 1 below summarises trends of variation in body weight and leucocyte level in CY and control mice.

References

Migiyama Y, Yanagihara K, Kaku N, Harada Y, Yamada K, Nagaoka K et al. Pseudomonas aeruginosa bacteraemia among immuno-competent and immuno-compromised patients: relation to initial antibiotic therapy and survival. Jpn J Infect Dis. 2016;69(2):91-6. Web.

Rhee C, Jones TM, Hamad Y, Pande A, Varon J, O’Brien C, Anderson DJ, et al. Prevalence, underlying causes, and preventability of sepsis-associated mortality in US acute care hospitals. JAMA Netw Open. 2019;2(2):1-14. Web.

Kim HS, Park BK, Kim SK, Han SB, Lee JW, Lee DG, et al. Clinical characteristics and outcomes of Pseudomonas aeruginosa bacteraemia in febrile neutropenic children and adolescents with the impact of antibiotic resistance: a retrospective study. BMC Infect Dis. 2017;17(500): 1-10. Web.

Greenhalgh DG. Sepsis in the burn patient: a different problem than sepsis in the general population. Burns Trauma. 2017;5(23):1-10. Web.

Holcomb, ZC. Fundamentals of descriptive statistics. Los Angeles: Taylor & Francis; 2016.

Introduction

Babesiosis is a communicable infection caused by protozoa that belong to the phylum Apicomplexa and genus Babesia (Hunfeld, Hildebrant and Gray 1219). These parasites invade the red blood cells to cause disease and have the ability to infect a wide range of vertebrate hosts such as cattle, human beings, and birds. Babesiosis has high incidence rates in North America particularly in the United States through other cases have been reported in countries such as Egypt, Korea, and South Africa (Gray et al. 3). Human babesiosis is caused by Babesia microtia, which is “a rodent-borne piroplasm, and also occasionally by a newly recognized species, the so-called WA1 piroplasm” (Homer et al. 451). Babesia microti needs proficient vertebrate and nonvertebrate hosts to sustain its transmission cycle (Homer et al. 451). In this case, ixodid ticks are responsible for the dissemination of the parasites to the vertebrate host. Other species such as Babesia divergens, Babesia venatorum, and Babesia duncani are also known to affect humans (Gray et al. 4).

Human babesiosis may present slight flu-like signs or no symptoms at all in approximately a quarter of infected adults and half of the infected children making the disease go undiagnosed in many instances (Gray et al. 4). However, if the patient is splenectomized or is on immunosuppressive medication very severe symptoms such as hemoglobinuria (the presence of hemoglobin in the urine), relentless high fever, severe sweating, headache, and abdominal pain may occur. These symptoms greatly resemble those experienced in malaria. Babesiosis may also induce critical difficulties such as acute malfunction of the respiratory system, congestive heart breakdown, coma, and failure of the kidney.

This paper looks at the pathogenesis of Babesia microti, which is the most common Babesia species that cause human babesiosis. It pays attention to the life cycle of the parasite in the progression of the disease as well as the accompanying side effects.

Pathogenesis

The life cycle of Babesia microti in the human host begins with the transfer of sporozoites from the salivary gland of the tick into the host bloodstream during feeding. Blood transfusion with contaminated blood may also introduce sporozoites into the bloodstream of healthy individuals. The effectiveness of sporozoite transmission is directly proportional to the duration of contact between the tick and the host (Homer et al. 454). The sporozoites infect red blood cells (erythrocytes) where they multiply by binary fission. In the erythrocytes, the sporozoites develop into multinucleated schizonts, which undergo further differentiation to form merozoites. The merozoites grow off from the schizonts. They then lyse the red blood cells and continue infecting other red blood cells. The parasites exhibit a high rate of reproduction that causes immense harm to the host cells.

The key pathological occurrence of serious infection is hemolysis (the bursting of the red blood cells) as a consequence of erythrocyte infestation by sporozoites. This leads to hemolytic anemia and jaundice (Gray et al. 4), which can further lead to anoxia and toxic outcomes thereby causing loss of life and organ breakdown in the absence of medical intervention. The extent of anemia does not correlate with the parasitemia (magnitude of infection or number of parasites in the system) suggesting that other mechanisms play a significant role in the progression of the disease. It is thought that pro-inflammatory cytokines are produced in abundance leading to symptoms such as fever, renal deficiency, clotting difficulties, muscle pain, and low blood pressure.

There is an immense correlation between the pathogenesis of babesiosis and the normal host immune response to infections and parasite-generated alterations in the membrane of the red blood cells (Vannier and Krause 2401). According to Hunfeld et al., the changes in the surface of the membranes of the red blood cells promote their clearance in the spleen (1227). In the mild instances of babesiosis, “inflammatory cytokines (e.g., tumor necrosis factor α [TNF-α] and interleukin-6) and adhesion molecules (e.g., E-selectin, intracellular adhesion molecule 1 [ICAM-1], and vascular-cell adhesion molecule 1 [VCAM-1]) are up-regulated” (Vannier and Krause 2401). The overproduction of cytokines amplifies the magnitude of the immune response thereby leading to severe babesiosis and its related difficulties such as high fever and immense pain.

The sequestration of white blood cells and the parasite-infected red blood cells may result in the blockage of the microvasculature as well as a reduction in the oxygen content of the tissues. Proteins may also be transported to the exterior of the affected red blood cells. Such protein-coated red blood cells tend to stick to the inner surface (endothelium) of the blood vessels and in so doing slow down their elimination by the spleen. While trying to get rid of infected red blood cells, the body’s immune system may also eliminate uninfected erythrocytes. Such nonhemolytic machinery also worsens anemia in patients suffering from babesiosis.

In vitro experiments and studies on B. microti using animal models (mice and cattle) provide information on the pathogenesis of human babesiosis. It is shown from such studies that cellular immunity has an upper hand over humoral immunity in containing babesiosis (Hunfeld et al. 1227). This is evident in mice experiments where T helper cells play a significant role in keeping parasitemia under control. These findings are consistent with the inability of immunocompromised patients to control unrelenting parasitemia. In the same way, a reduction of natural killer cells and macrophages makes individuals more vulnerable to babesiosis infection. All these findings lead to the conclusion that the pathobiology of babesiosis is not a consequence of the parasite, but the host immune response.

Splenectomy, which is the surgical removal of the spleen, increases the risk of babesiosis. This is because the spleen performs a crucial function in host protection by eliminating infected red blood cells from the bloodstream. In addition, the spleen is a secondary lymphoid organ and participates in intensifying a protective immune rejoinder.

Conclusion

Babesiosis is a rare ailment that can occur in mild or severe forms. The mild form of babesiosis is asymptomatic and may resolve itself without any treatment. On the other hand, the severe form of babesiosis exhibits conspicuous symptoms such as fevers, chills, fatigue, and aches. The symptoms and pathogenesis of babesiosis closely resemble those of malaria infection. In addition, both parasites belong to the phylum Apicomplexa making it hard to distinguish between the two infections. The immune system plays a crucial role in controlling babesiosis thereby making immunocompromised individuals and the elderly highly predisposed to infections. It is also known that most symptoms experienced during the illness are consequences of the host immune response against the disease. Therefore, there is a need to establish efficient diagnostic tools to help in the distinction between babesiosis and malaria infections and ensure that patients get timely interventions to minimize the loss of lives from babesiosis.

Works Cited

Gray, Jeremy, Annetta Zintl, Anke Hildebrandt, Klaus-Peter Hunfeld, and Louis Weiss. “Zoonotic Babesiosis: Overview of the Disease and Novel Aspects of Pathogen Identity.” Ticks and Tick-Borne Diseases 1.1 (2010): 3–10. Print.

Homer, Mary J., Irma Aguilar-Delfin, Sam R. Telford, Peter J. Krause, and David H. Persing. “Babesiosis.” Clinical Microbiology Reviews 13.3 (2000): 451-469. Print.

Hunfeld, K.-P., A. Hildebrandt and J. S. Gray “Babesiosis: Recent Insights into an Ancient Disease.” International Journal for Parasitology 38.11 (2008): 1219–1237. Print.

Vannier, Edouard and Peter J. Krause. “Human Babesiosis.” The New England Journal of Medicine 366.25 (2012): 2397-2407. Print.