Reservoirs Of Nosocomial Pathogens Research Articles

Reservoirs of Nosocomial Pathogens in Intensive Care Units: A Systematic Review.

Nosocomial pathogens are known to exacerbate morbidity and mortality in contemporary critical healthcare. Hospital fomites, which include inanimate surfaces, have been identified as "breeding grounds" for pathogens that cause nosocomial infections. This systematic review aimed to deliver incisive insights on nosocomial pathogens in intensive care units (ICUs) and the role of fomites as potential reservoirs for their transmission. An extensive exploration of electronic databases, including PubMed and Scopus, from 1990 to 2023, was carried out between 25th and 29th May 2023, per standard PRISMA guidelines. Information were extracted from articles that reported on fomites in the ICU. Studies that did not quantitatively report the fomite contamination, and those that exclusively took samples from patients in the ICU were excluded from the analysis. About 40% of the total samples collected on fomites from all the studies yielded microbial growth, with species of Staphylococcus being the most predominant. Other prevalent microbes were Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Candida spp., Enterococcus sp., and Enterobacter sp. The neonatal intensive care unit (NICU) had the highest proportion of contaminated fomites. Among known fomites, the sphygmomanometer exhibited a 100% detection rate of nosocomial pathogens. This included E. aerogenes, Staphylococcus aureus, coagulase-negative Staphylococci (CoNS), E. coli, and K. pneumoniae. Multidrug-resistant (MDR) bacteria, such as methicillin-resistant S. aureus (MRSA), vancomycin-resistant Enterococci (VRE), extended-spectrum beta-lactamase (ESBL)-producing E. coli, and MDR Pseudomonas aeruginosa were commonly isolated on fomites in the ICUs. Many fomites that are readily used in patient care in the ICU harbour nosocomial pathogens. The most common fomite appeared to be mobile phones, sphygmomanometers, and stethoscopes, with Staphylococcus being the most common contaminant. Consequently, the need for rigorous disinfection and sterilization protocols on fomites in the ICU cannot be overemphasized. Additionally, heightened awareness on the subject among health professionals is crucial to mitigating the risk and burden of nosocomial infections caused by drug-resistant bacteria.

The role of water distribution system in HCAIs

Abstract Introduction The water distribution system in hospitals may constitute a source of healthcare-associated infections. Understanding the means of acquisition, sources and reservoirs of nosocomial pathogens is crucial for developing methods to reduce the incidence of nosocomial infections. The aim of our study was to evaluate the microbiological contamination by Pseudomonas aeruginosa in the water system of the University Hospital “G. Martino” in Messina over a period of nine years, in order to a) clarify possible relationship between the presence of aerators and contamination, b) to highlight the presence of a yearly variation and c) to verify the statistical difference between microbiological contamination of taps with and without filters. Materials and Methods We carried out a retrospective study for nine year through the collection of water samples that were analysed for total bacteria count and Pseudomonas aeruginosa. The differences between the results recorded over the nine-year study period were evaluated using variance analysis. P values of < 0.05 were considered statistically significant. Software R was used for statistical assessment. Results We analysed a total of 6168 samples with a positive rate of 9.31% and a decreasing trend over the nine years to a value of 2.44% (p < 0.001), due to the elimination of the aerators of taps without filters and also to the introduction of filters in taps of high-risk wards and surgical rooms. We found statistical difference between taps with or without filter (p < 0.001) and a higher positive rate during the summer season compared to the other months. Also, an increase of the positivity rate was detected in some year due to the lack of monthly replacement of the filter. Conclusions These results reveal a high level of contamination of taps by opportunistic bacteria with severe implications especially for high-risk settings and therefore, the need to improve the management of these devices. Key messages Particular attention must be reserved to the water distribution systems in hospitals in order to prevent the spread of healthcare associated infections. The continued application and strengthening of guidelines and procedures is essential to limit the spread of multidrug resistant pathogens.

1211. Microbiologic Evaluation of Mobile Phones and Hands of Healthcare Professionals in Two Intensive Care Units in a Brazilian University Hospital

BackgroundHealthcare-associated infections (HAIs) are a worldwide concern because of their high morbidity, mortality, and associated costs. Mobile phones (MP) are an important work tool in the healthcare setting, but they can be a reservoir of nosocomial pathogens if not carefully cleaned and cause re-contamination of the healthcare professional’s (HCP) hands. We aimed to evaluate bacterial colonization of HCP’s hands and their respective MPs.MethodsA cross-sectional study was performed in two Intensive Care Units (ICUs), an internal medicine and a burn unit, of a Brazilian tertiary university hospital. These units were chosen because of their different hand hygiene (HH) compliance. We assessed HH and MP handling practices by an electronic inquiry and collected samples from the dominant hand (DH) by the sterile bag technique and of MPs by moistened sterile swab. MALDI-TOF was used for bacterial identification and Dilution Agar (DA) was used to screen Gram-negative bacteria (GNB) susceptibility to carbapenems and colistin.ResultsForty-seven HCPs were evaluated; of whom, 30% were medical residents, 19% nurses, 17% nurse-technicians, 17% physiotherapists, 13% cleaning staff, and 4% radiology technicians.Overall, 85% of HCPs reported use of MP at work, 26% had never cleaned it, and 34% reported optimal HH compliance practices. All of them believed that MPs can have HAIs agents. DH culture showed 94% of colonization and the most common Gram-positive bacteria (GPB) and GNB were S. epidermidis (n = 17∕44) and A. baumannii complex (n = 11∕44), respectively. MP were colonized in 89% of the cases and the most common GPB and GNB were S. epidermidis (n = 16∕42) and Pseudomonas spp (n = 9∕42), respectively. Overall, in the screening 38% of GNB were resistant to meropenem and 22% to colistin. A. baumannii was the most common meropenem (n = 4) and colistin (n = 2) resistant GNB. In the two units, 32% of HCPs had the same microorganism species isolated in the MP and in the DH (Table 1).ConclusionThere was a high rate of bacterial colonization on the MP and DH of HCPs and some of these bacteria were carbapenem or colistin resistant. A policy for MP handling in the healthcare setting should be implemented in order to avoid cross-contamination between the MP and the hand of HCPs. Disclosures All authors: No reported disclosures.

Photodynamic antimicrobial polymers for infection control.

Hospital-acquired infections pose both a major risk to patient wellbeing and an economic burden on global healthcare systems, with the problem compounded by the emergence of multidrug resistant and biocide tolerant bacterial pathogens. Many inanimate surfaces can act as a reservoir for infection, and adequate disinfection is difficult to achieve and requires direct intervention. In this study we demonstrate the preparation and performance of materials with inherent photodynamic, surface-active, persistent antimicrobial properties through the incorporation of photosensitizers into high density poly(ethylene) (HDPE) using hot-melt extrusion, which require no external intervention except a source of visible light. Our aim is to prevent bacterial adherence to these surfaces and eliminate them as reservoirs of nosocomial pathogens, thus presenting a valuable advance in infection control. A two-layer system with one layer comprising photosensitizer-incorporated HDPE, and one layer comprising HDPE alone is also described to demonstrate the versatility of our approach. The photosensitizer-incorporated materials are capable of reducing the adherence of viable bacteria by up to 3.62 Log colony forming units (CFU) per square centimeter of material surface for methicillin resistant Staphylococcus aureus (MRSA), and by up to 1.51 Log CFU/cm2 for Escherichia coli. Potential applications for the technology are in antimicrobial coatings for, or materials comprising objects, such as tubing, collection bags, handrails, finger-plates on hospital doors, or medical equipment found in the healthcare setting.

Attitudes and beliefs, not just knowledge, influence the effectiveness of environmental cleaning by environmental service workers

Hospital environmental service workers (ESWs) play an important role in interrupting the chain of infection because the environment is a reservoir for nosocomial pathogens. Improving ESWs' knowledge through education has been shown to improve ESW cleaning, but the behavioral determinants of their work have not been studied. Understanding and targeting ESWs' attitudes and beliefs may inform strategies to improve environmental cleaning. With the theory of planned behavior as framework, we used questionnaires and focus groups to examine intensive care unit ESWs' attitudes, beliefs [behavioral, normative, and control], and control) and intent about their job. Baseline quantitative microbial cultures of high-touch services were performed before and after cleaning. After an educational intervention addressing their attitudes, beliefs, and general infection control knowledge, attitudes, beliefs, and microbial contamination were reassessed. Beliefs were uniformly strong (4.5/5-5/5), and normative beliefs correlated best with intent to clean (R(2) = 0.3). Themes elicited from the focus groups included "me versus them," lack of appreciation, pride in work, and "if it were me." The rate of environmental contamination was significantly improved after the intervention (P = .0074 vs P = .0023, respectively); the measured relationship among attitudes, beliefs, and intent was not significantly changed. ESWs' attitudes and beliefs about their job may impact their intent to clean and in turn the effectiveness of their efforts. Understanding and addressing these attitudes and beliefs can be used to inform strategies for sustained improvement of environmental cleaning.

Neonatal intensive care unit: reservoirs of nosocomial pathogens.

Improvement in the care and treatment of neonates had contributed to their increased survival. Nosocomial infection remains an important problem in intensive care units. Hospital wards had been shown to act as reservoirs of pathogenic microorganisms associated with infection. To assess the prevalence of pathogenic organisms in the environment of the neonatal unit, 92 swabs were randomly collected from cots, incubators and various equipments in the unit and were cultured on Blood agar and MacConkey agar plates. Air contamination was detected by exposing the same types of agar plates for 3 hours in several areas of the unit. After 48 hours incubation, isolates were identified biochemically. There is marked congestion in the unit. Ninety one percent of swabs yielded growth, with coagulase negative Staphylococcus being the predominant organism (44%), followed by Bacillus species (20%), E. coli (12.5%), and Klebsiella (8.5%), Pseudomonas species (3.6%) and moulds (3.6%). Sedimentation plates had colony counts of from 10 - 100 per plate and the majority of the cultures were polymicrobial cultures. The presence of various Gram-negative bacili including known neonatal pathogens (like E. Coli and Pseudomonas) especially on ward equipment and congestion in the ward has the potential to cause nosocomial infection.

Enteral feeding tubes are a reservoir for nosocomial antibiotic-resistant pathogens

Background: Patients and their surroundings are known reservoirs for nosocomial pathogens. Enteral feeding tubes and formula are not thought of as reservoirs for nosocomial organisms. Methods: A prospective observation study was conducted comparing methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) cultured from nosocomial infections and MRSA/VRE cultured from enteral feeding tubes used in the same neonatal intensive care unit during the same time period but in different babies. DNA fingerprinting then was used to compare MRSA and VRE cultured from feeding tubes with MRSA/VRE isolates cultured from clinical infections. Results: There were 23 S aureus isolates; 12 of 23 were methicillin resistant (MRSA). There were 4 MRSA infections in patients without feeding tubes. DNA fingerprinting showed that the MRSA species causing each of the clinical infections also was found in the feeding tubes of other babies. There were no vancomycin-resistant Enterococcus infections during the study period. Conclusion: Feeding tubes are a reservoir for antibioticresistant pathogens that can be transmitted to other infants. J Pediatr Surg 37:1011-1012. Copyright 2002, Elsevier Science (USA). All rights reserved.

Computer keyboards and faucet handles as reservoirs of nosocomial pathogens in the intensive care unit

Purpose: We postulate that computer keyboards and faucet handles are significant reservoirs of nosocomial pathogens in the intensive care unit (ICU) setting. Methods: Sterile swab samples were obtained from 10 keyboards and 8 pairs of faucet handles in the medical ICU at Tripler Army Medical Center during a period of 2 months. Methicillin-resistant Staphylococcus aureus (MRSA) obtained from the environmental and patient specimens were sent for DNA identification by using pulsed-field gel electrophoresis. Results: A total of 144 samples were obtained (80 keyboards and 64 faucet handles), yielding 33 isolates. The colonization rate for keyboards was 24% for all rooms and 26% in occupied rooms. Rates for faucet handles in all rooms and occupied rooms were 11% and 15%, respectively. The environmental isolates annd their prevalence were: MRS, 49%; Enterococcus, 18%; Enterobacter, 12%; and all other gram-negative rods, 21%. Fourteen individual patient isolates were recorded: MRSA, 43%; Enterobacter, 21%; other gram-negative rods, 36%; and Enterococcus, 0%. By using pulsed-field gel electrophoresis, an indistinguishable strain of MRSA was identified in two patients, the keyboards and faucet handles in their respective rooms, and on other keyboards throughout the ICU, including the doctors’ station. Conclusions: The colonization rate for keyboards and faucet handles, novel and unrecognized fomites, is greater than that of other well-studied ICU surfaces in rooms with patients positive for MRSA. Our findings suggest an associated pattern of environmental contamination and patient infection, not limited to the patient’s room. Pulsed-field gel electrophoresis results have documented an indistinguishable strain of MRSA present as an environmental contaminant on these two fomites and in two patients with clinical infections patients during the same period. We believe these findings add evidence to support the hypothesis that these particular surfaces may serve as reservoirs of nosocomial pathogens and vectors for cross-transmission in the ICU setting. New infection control policies and engineering plans were initiated on the basis of our results. (AJIC Am J Infect Control 2000;28:465-70)

Reservoirs of Nosocomial Pathogens at a University Teaching Hospital In Nigeria

Two hundred and seventy seven microorganisms were isolated between February and August 1998 from surgical and medical wards including the haemodialysis unit and microbiology laboratory of a University Teaching Hospital in Lagos, Nigeria. Environmental Contamination was high. Medical and surgical wards accounted for the highest contamination rates of 67% and 63% respectively; followed by the microbiology laboratory, 48% and the Haemodialysis unit, 30%. Within the wards, the areas most contaminated were the sinks, bedpans, wastebins, mattresses and toilet seats, Staphylococcus aureus was the most commonly isolated organism with a prevalence rate of 39.3% closely followed by Klebsiella pneumoniae, 24.6%. Others were coagulase-negative Staphylococci, 13.7%; Escherichia coli, 8.3% Pseudomonas aeruginosa, 9.0%, Proteus mirabilis, 1.8%; Citrobacter freundii, 1.1%; Proteus vulgaris, 0%; Salmonella paratyphi A, 0.7%; Enterobacter aerogenes, 0.4% and Salmonella typhi, 0.4%. Antibiograms of the isolates suggested three clusters of Staphylococcus aureus, groups SA1, SA2 and SA3. The largest group SA!, present in the Medical wards, Surgical wards, Microbiology laboratory and the haemodialysis unit, was Methicillin-sensitive. SA2 was present in only the medical and surgical wards while SA3 was only found in the surgical wards. Two clusters each, KP1 and KP2 of Klebsiella pneumoniae and EC1 and EC2 of Escherichia coli were obtained while there was only one cluster, PA1, of Pseudomonas aeruginosa. KP1, EC1 and PA1 were found in all the wards. Lack of adequate running water and poor environmental sanitation were major contributory factors to the high contamination rates. [J. of the Nig. Infection Control Assn. Vol.3(2) 2000: 18-24]

Water as a Reservoir of Nosocomial Pathogens

Understanding the means of acquisition, sources, and reservoirs of nosocomial pathogens is crucial for developing methods to reduce the incidence of nosocomial infections. The article in this issue by Graman et all highlights the continued importance of the environment, especially water sources, as a reservoir for nosocomial pathogens. Important water reservoirs in the hospital include potable water, sinks, faucet aerators, showers, tub immersion, toilets, dialysis water, ice and ice machines, water baths, flower vases, eyewash stations, and dental-unit water stations (Table). This editorial will review water as an important reservoir of nosocomial pathogens, with a focus on methods for prevention and control.

Water as a Reservoir of Nosocomial Pathogens

Water as a Reservoir of Nosocomial Pathogens