Infections contribute to the adverse health consequences more probably in hospital settings. A myriad of pathogenic agents contends to invade the hygienic chain of susceptible individuals. The underlying reasons that are responsible for the problem may be a sterile-free hospital environment that has become a breeding ground for the pathogenic microorganisms.
The microorganisms even become drug-resistant and continue their life cycle. The management of such microorganism-led infections has become a major task for health care professionals. These infections are better regarded as nosocomial infections.
These infections contribute to conditions like sepsis to a higher degree. It was reported that most infections originate in departments of pediatrics or neonatal units, intensive care units (ICU) (www.cdc.gov/ncidod/dhqp/nnis_pubs.html). Adults also run the risk of acquiring infections. Adult nosocomial infection rates in ICUs are 5-10 times more than that of general ward patients (Trilla, 1994). Emerging incidence rates claim 1.7 million infections and 99,000 mortalities per annum in countries like the United States. (www.cdc.gov/ncidod/dhqp/nnis_pubs.html). There are several research reports across the globe as far as the adverse health impact of nosocomial infections. There is a need to explore them to gain better insights into the emerging trends in nosocomial infections. The surveillance data from Japan has indicated a high incidence of nosocomial infections in ICUs across various hospitals of the country (Machi Suka, Katsumi Yoshida & Jun Takezawa, 2008). This was found to be significantly correlated with mortality and duration of hospital stay (Machi Suka, Katsumi Yoshida & Jun Takezawa, 2008). This study has compared their findings with that of the United States and described that they had a narrow focus on the nosocomial infection epidemiology, indicating the need for a good number of surveillance studies. The ultimate objective was to prepare a curriculum and methodology for determining the data related to the surveillance of infection which might facilitate the infection monitoring authorities to build –up their independent or surveillance paradigms for a smooth flow of work (Machi Suka, Katsumi Yoshida & Jun Takezawa, 2008).
Hence, the risk management of emerging nosocomial infections should require strong support from the surveillance data obtained through multinational collaboration.
With the advancements in the field of Molecular Biology, much emphasis was given to the process of genotyping important pathogens. In a study, researchers have chosen the genotypes G and P of rotavirus (Jung Oak Kang et al., 2006. These are reported to be distributed among children of age range 2-12 and who have a record of hospitalization with complaints like diarrhea (Jung Oak Kang et al., 2006). Here, isolates have been characterized through isolation and genes amplified by the multiplex PCR (polymerase chain reaction) technology (Jung Oak Kang et al., 2006). The severity in the emergence of this pathogen was better found when there were common strains with their parentages escalating from 1, 5 % to 65 % for the strains like G1P, G4P, G3P, and G2P (Jung Oak Kang et al., 2006). Most of the victims were newborns with an infection percentage of 82.6 characteristics of G4P. it was found that the infection has resulted in the manifestation of dehydration, fever, diarrheal illness, nausea, fever (Jung Oak Kang et al., 2006). This genotype has implications because of its potential to exist in diverse G4P, forms that could be important for its epidemiology (Jung Oak Kang et al., 2006). To say, the chief high-risk strain is G4P in newborns but the latest research has shed light on the G9P  as the novel emerging strain worldwide when it was discovered in developing countries like Korea(Jung Oak Kang et al., 2006).
This could indicate that pathogens have the inherent property of causing infections with the diversity in their localization or habitat. Newborns susceptible to rotavirus infections are at high risk of developing complications that could lead to even fatal conditions in the most adverse cases. There may be a high chance of both strains gaining entry into the hygienic life of a newborn and causing serious problems. Hence, it was inferred that the genotype that is playing the leading role in the emergence of nosocomial rotavirus infections is G4P and G9 in hospital settings.
The next pathogen to be discussed in the context is Candida parapsilosis. This microbe was considered one of the emerging pathogenic agents of human beings. Its importance and prevalence rates have become a concern as it was reported to contribute to invasive candidal disease. The individuals who fall victims to this pathogen are hospitalized patients and neonates more particularly staying in ICUs.
Infections characteristic of C. parapsilosis are strongly connected to the use of indwelling catheters, prosthetic devices, hyperalimentation solutions, and health care workers with their contaminated hands (David Trofa, Attila Gácser &Joshua, 2008). The emergence of this infection could be attributed to the hydrolytic enzyme secretion, prosthetic adhesion, and formation of biofilms (David Trofa, Attila Gácser & Joshua, 2008). Molecular biology has made feasible the management of virulence of C. parapsilosis. Severely low birth neonates carry a high risk of acquiring Nosocomial infection typical of C. parapsilosis(David Trofa, Attila Gácser & Joshua, 2008). This pathogen mainly inhabits the skin or gastrointestinal (GI) tract for penetration. As neonates are delicate in their skin roughness or texture, they are vulnerable to GI tract infection resulting in the enhanced requirement of central venous catheters, and even endotracheal intubation for a long duration(David Trofa, Attila Gácser & Joshua, 2008). The emergence of infection is also attributed to the roots linked to the hands of health care workers more probably, nurses and physicians. (David Trofa, Attila Gácser & Joshua , 2008). Candida species is responsible for the emergence of nosocomial infections more pertaining to central nervous system disorders meningitis like neutrophilic meningitis(David Trofa, Attila Gácser & Joshua, 2008). Lymphocytic meningitis is caused by Cryptococcus neoformans whereas granulomatous meningitis is by Coccidioides species(David Trofa, Attila Gácser & Joshua, 2008). The disease is manifested by fever, headache, delirium, and nuchal rigidity. (David Trofa, Attila Gácser & Joshua , 2008)
Similarly, Candida also causes peritonitis for which the death rate was reported to be 44%(David Trofa, Attila Gácser & Joshua, 2008).
This disease was reported to affect individuals with complaints related to end-stage renal disease patients on therapy with continuous ambulatory peritoneal dialysis (CAPD) (David Trofa, Attila Gácser & Joshua, 2008). Further, Candida species also plays role in the development of Fungal arthritis in elderly individuals. Occular infections of Candida lead to endophthalmitis and keratitis. The emergence of this disorder has become problematic with the associated requirements like corticosteroid eye drop and cataract extraction (David Trofa, Attila Gácser & Joshua, 2008). Ear infections are known as Otomycosis rarely contribute to otitis media or externa and other related severe ear complications. Onychomycosis, nail infections, Ulvovaginitis, and Urinary Tract Infections(David Trofa, Attila Gácser & Joshua, 2008). Therefore, with the above-mentioned disease-causing spectrum of Candida species, the emergence has evolved into an ever-growing problem for healthcare professionals Hence there is a need to circumvent the spread of Candia species at the earliest stage(David Trofa, Attila Gácser & Joshua, 2008)
The other microbe to be discussed is Leuconostoc species’’. These are well-known gram-positive microbes most commonly cause various infections in humans (Germán Bou et al., 2008). This microbe was reported to emerge as the problematic pathogen in individuals receiving treatment with drugs like vancomycin and those with their immune system compromised (Germán Bou et al., 2008). This pathogen is reported to cause outbreaks through hospital transmission. Nearly 88 cases of infections caused by Leuconostoc have been reported from various parts of the world in the past 25 years. This may indicate the emergence of this pathogen as the important source of nosocomial infections
However, data is further needed to establish a strong genetic association among the strains involved in the episodes of nosocomial infections (Germán Bou et al., 2008).
Vancomycin-resistant Enterococci (VRE) are one of the leading health problems in the US (www.phageinternational.com). Nearly, 300,000 patients who have developed malignant tumors are susceptible becoming susceptible to the risk of developing infection with VRE each year in the U. S. Earlier in 1999 ICUs have a good record of acquiring VRE-associated bacterial infections which were reported to be a 47% increase from 1974(www.phageinternational.com).VRE infections are more in those individuals who spent a long duration in hospitals and ICU stays. VRE infection is most common in 14% of patients in adult oncology units (www.phageinternational.com). The other patient groups who run the risk of VRE infection are those on chemotherapy, radiotherapy, or immunosuppressive compounds (www.phageinternational.com)
In a previous study, an emerging health issue was associated with the microbe Pseudomonas aeruginosa in a hospital-based setting (Anthony et al., 2002). This pathogen was reported to acquire resistance to antibiotics like piperacillin-tazobactam in individuals on long hospital stays (Anthony et al., 2002).
Pseudomonas aeruginosa is the major contributor of nosocomial infections and has achieved 5th position among the pathogens recorded in the database of the National Nosocomial Infection Surveillance System (Anthony et al., 2002). This pathogen was responsible for causing emerging incidence rates and has become mandatory in the research due to several reasons(Anthony et al., 2002). This pathogen offers a platform for high-risk individuals, with resistance to microorganisms, to be noticed at an earlier stage (Anthony et al., 2002).
This could facilitate the health care professionals easy management of the infections
This pathogen also helps in smooth access of information relate to the disease incidence, epidemiology, etiopathogenesis caused by antibiotic-resistant organisms (Anthony et al., 2002). It also enables us to understand the risk factors that play a vital role in the process like shifts in the mode of the utility of antibiotic usage which could lessen the emergence of microorganisms that cause antibiotic resistance in patients (Anthony et al., 2002).
Nosocomial pneumonia is considered to be an important nosocomial infection in the USA as it is the second most common nosocomial infection (www.wrongdiagnosis.com). The affected patients develop respiratory tract and cause nosocomial pneumonia: bacterial pneumonia, Legionnaires’ disease, pulmonary aspergillosis, Mycobacterium tuberculosis, and viral pneumonia such as Respiratory Syncytial Virus (RSV) and influenza (www.wrongdiagnosis.com).
The other factors identified are the duration of hospital or ICU stay, shifting between medical institutions, overall high rate of admissions in the earlier year(Anthony et al., 2002).Much case – control investigations were focused on nosocomial isolation of piperacillin-tazobactam-resistant P. aeruginosa, and piperacillin-tazobactam-susceptible P. aeruginosa(Anthony etal., 2002). It was revealed that there were differences in the mode of susceptibility of antibiotics to the bacterium (Anthony et al., 2002). In other words, the antibiotics that show piperacillin-tazobactam-susceptibility to P. aeruginosa were different from antibiotics that show piperacillin-tazobactam-resistance to P. aeruginosa (Anthony et al., 2002). This has indicated that nosocomial infections caused by P. aeruginosa may have multidrug antibiotic resistance. Therefore, it was described that piperacillin-tazobactam was considered as the potential risk contributing agent for inducing resistance in P. aeruginosa (Anthony et al., 2002). The emerging trends in nosocomial infections could be attributed to the mode of action of multiple antibiotics (Anthony et al., 2002). However, restricting the utility of piperacillin-tazobactam would not alleviate the problems concerned with the emerging strains of piperacillin-tazobactam-resistant P. aeruginosa (Anthony et al., 2002). The research may need better approaches to address this problem which could be more likely anticipated in the near future. The next microbe is known to cause nosocomial infections is Staphylococcus aureus. This microbe has acquired the name methicillin-resistant Staphylococcus aureus (MRSA), due to its potent drug resistance.
In the US, many people were reported to die due to MRSA in hospital settings when compared to AIDS as per the CDC report. Further, MRSA contributed to 94,000 life-threatening infections and 18,650 deaths in 2005, according to the Journal of the American Medical Association. Next, in the US adult, more than 65 years were reported to run the risk more than the general population to get an MRSA infection. Nearly, 128 cases were reported to occur for every 100,000 adult individuals more than 65 years of age.
For this purpose, MRSA isolates have to be collected from a large population screening study. The ultimate objective is to pool up nosocomial isolates and identify 3 major pulsotypes (A, B, and C) (Jann-Tay Wang et al., 2007). The pulse type A should be isolated in the first six months followed by the subsequent types B and C in the next twelve months (Jann-Tay Wang et al., 2007). This facilitates a smooth characterization and hectic free research methodology. Multiplex PCR may offer the broad choice for easy identification of MRSA. Hence its utility should be considered in addressing the problem.
In view of the above, nosocomial infections have become the good choice of life science researchers to address the problems evolving at a high rate. Infections related to MRSA, Vancomycin, and Pneumonia are escalating the health problems in countries like the US.
So, there is a need for the health care policymakers to interfere at the earliest in order to circumvent the ever-increasing incident cases which could be possible with a large number of studies.
Prevalence and current status
Nosocomial infections carry a high risk of hospital-acquired infections. Surveillance data reported from various studies have indicated infections close to 2 million and 100000 mortalities per year in developed countries (www.cdc.gov/ncidod/dhqp/nnis_pubs.html).
Types of cases
The most frequent nosocomial infection and their incident cases are pneumonia – 517 cases, sepsis -106 cases, wound infection -102 cases, urinary tract infection – 43 cases, and catheter-related bloodstream infection-42 cases (Machi Suka, Katsumi Yoshida & Jun Takezawa, 2008).
Nosocomial infections were reported to carry drug resistance due to the action of a good number of microbes, identified to date.
- Vulnerable sites: These are mostly associated with hospital-based settings, ICU’s neonatal units, and with the utility of devices like urinary catheters and hands of health care professionals like nurses and physicians.
- High-risk groups and types of pathogens: Neonates and children carry a high risk of acquiring nosocomial infections due to their susceptible body development. This is the case with the genotypes G and P of rotavirus. Patients staying in ICUs have become targets for pathogens like Candida species. The nonsocial infections characteristic of this pathogen invades skin, nails, ear, and central nervous system urinary system, which results in severe deformities. Next, Leuconostoc species are among the microbes carrying potential risk for nosocomial infections in clinical settings and in patients on unhygienic parenteral nutrition. (Germán Bou et al., 2008). Pseudomonas aeruginosa is one of the contributing agents of nosocomial infections due to its ability to combat the action of antibiotics like piperacillin-tazobactam (Anthony et al., 2002).
The last and most important microbe in the description is that of Staphylococcus aureus. This pathogen is responsible for severe infections due to its resistance to methicillin and hence the name methicillin-resistant Staphylococcus aureus (MRSA) (Jann-Tay Wang et al., 2007).
Control of infection
The management of nosocomial infections related to the above-mentioned microbes could be made feasible by the large population screening for the isolation and characterization of isolates, genotyping and sequencing of potential strains that exhibit remarkable diversity.
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