Significance of methicillin-resistant Staphylococcus aureus (MRSA) survey in a university teaching hospital

In vitro study on the transmission of multidrug-resistant bacteria from textiles to pig skin

BACKGROUND

The survival of microorganisms on textiles and specifically on healthcare professionals' (HCP) attire has been demonstrated in several studies. The ability of microorganisms to adhere and remain on textiles for up to hours or days raises questions as to their possible role in transmission from textile to skin via HCP to patients.

AIM

To evaluate the presence, survival and transmission of different multidrug-resistant bacteria (MDRB) from HCP attire onto skin.

METHODS

Three MDRB [methicillin-resistant Staphylococcus aureus (MRSA); vancomycin-resistant Enterococcus faecium (VRE); carbapenem-resistant Klebsiella pneumoniae, CRKP)] were inoculated on textiles from scrubs (60% cotton-40% polyester) and white coat (100% cotton) at concentrations of 108 colony-forming units (CFU), 105 CFU, and 103 CFU per mL. The inoculation of swatches was divided in time intervals of 1 min, 5 min, 15 min, 30 min, 1 h, 2 h, 3 h, 4 h, 5 h, and 6 h. At the end of each period, textiles were imprinted onto pig skins and each skin square was inverted onto three different selective chromogenic media. Growth from the pig skin squares was recorded for the 3 MDRB at the three above concentrations, for the whole length of the 6-h experiment.

RESULTS

MRSA was recovered from pig skins at all concentrations for the whole duration of the 6-h study. VRE was recovered from the concentration of 108 CFU/mL for 6 h and from 105 CFU/mL for up to 3 h, while showing no growth at 103 CFU/mL. CRKP was recovered from 108 CFU/mL for 6 h, up to 30 min from 105 CFU/mL and for 1 min from the concentration of 103 CFU/mL.

CONCLUSION

Evidence from the current study shows that MRSA can persist on textiles and transmit to skin for 6 h even at low concentrations. The fact that all MDRB can be sustained and transferred to skin even at lower concentrations, supports that textiles are implicated as vectors of bacterial spread.

Contamination of Clinical White Coats with Potential Pathogens and their Antibiotic Resistant Phenotypes Among a Group of Sri Lankan Medical Students

Background: Clinical white coats worn by the medical students can be contaminated at hospitals and act as a potential reservoir for pathogens including antibiotic-resistant bacteria. This study aimed to identify the contamination rates of clinical white coats worn by medical students with selected potential pathogens and their antibiotic resistant phenotypes. Methods: A cross-sectional study was done among 151 4th year medical students of Faculty of Medicine, University of Peradeniya, Sri Lanka in September 2020. The participants belonged to two batches undergoing clinical training at two settings. Swabs from pockets and sleeves of the clinical white coats were taken. Potential pathogens and their resistant phenotypes were identified with routine tests. Results: Fifty-three participants (35.1%) had coats contaminated with Staphylococcus aureus; 15 (9.9%) had coats contaminated with Methicillin-Resistant S.aureus (MRSA).  One Enterobacterales (0.7%) was an AmpC producer.  Enterococcus species were isolated from 19 (12.6%) coats and 2 (1.3%) had coats contaminated with vancomycin resistant enterococci.  Molecular testing on the MRSA isolates identified that 5(20%) of the MRSA isolates were PVL positive while all were mecA positive. Sex, type of clinical appointment, and frequency of washing white coats were not associated with contamination. The “batch” was significantly associated with contamination with S.aureus and Enterococcus species.  Conclusions: We found that clinical white coats worn by medical students recruited for the study were contaminated with S.aureus, MRSA and Enterococcus species. There was a notably high-rate of contamination with S. aureus.  All MRSA isolates were mecA positive while the rate of PVL positivity was low.

Study of the persistence of selected Gram-negative bacteria pathogens of healthcare-associated infections on hospital fabrics

BACKGROUND

The ability of healthcare associate infection (HAI) pathogens to persist on fomites is crucial to their transmission within the healthcare setting, this study evaluated the persistence of 3 common HAI pathogens on fabrics materials commonly used in healthcare settings.

METHODS

Persistence of bacteria species on fabric was investigate by inoculating standardized inoculum prepared from the clinical isolates of Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumannii on sterile swatches of 100% cotton, microfiber and polyester. Viable bacteria persisting on the inoculated fabrics were evaluated immediate after inoculation and subsequently at 96-hour interval for 32 days using the drop plate technique. The effect of moisture on the persistence of the studied bacteria isolates was also evaluated.

RESULTS

Between 3 and 6 log reduction in the viability of the inoculated bacteria cells were observed after 32 days of inoculation on fabrics. Generally, lower viable cells were recovered from the microfiber fabrics compared to others, while higher viable cells were recovered from wet fabrics compared to the dry fabrics in this study.

DISCUSSION AND CONCLUSIONS

This study demonstrated that HAI bacteria pathogens can persist for more than a month on hospital fabrics, and that their persistence can be enhanced by moisture.

Presence of Methicillin-Resistant Staphylococcus aureus (MRSA) on Healthcare Workers' Attire: A Systematic Review

Contaminated healthcare workers' (HCW) clothing risk transferring methicillin-resistant Staphylococcus aureus (MRSA) in healthcare facilities. We performed a systematic review in Pubmed and Scopus for 2000-2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to analyze evidence of MRSA on HCW attire. The primary study outcome was MRSA isolation rates on HCW clothing in healthcare settings. Out of 4425 articles, 23 studies were included: 18 with 1760 HCWs, four with 9755 HCW-patient interactions and one with 512 samples. There was a notable variation in HCWs surveyed, HCW attires, sampling techniques, culture methods and laundering practices. HCW attire was frequently colonized with MRSA with the highest rates in long-sleeved white coats (up to 79%) and ties (up to 32%). Eight studies reported additional multidrug-resistant bacteria on the sampled attire. HCW attire, particularly long-sleeved white coats and ties, is frequently contaminated with MRSA. Banning certain types and giving preference to in-house laundering in combination with contact precautions can effectively decrease MRSA contamination and spread.

The role of textiles as fomites in the healthcare environment: a review of the infection control risk

BACKGROUND

Infectious diseases are a significant threat in both healthcare and community settings. Healthcare associated infections (HCAIs) in particular are a leading cause of complications during hospitalisation. Contamination of the healthcare environment is recognised as a source of infectious disease yet the significance of porous surfaces including healthcare textiles as fomites is not well understood. It is currently assumed there is little infection risk from textiles due to a lack of direct epidemiological evidence. Decontamination of healthcare textiles is achieved with heat and/or detergents by commercial or in-house laundering with the exception of healthcare worker uniforms which are laundered domestically in some countries. The emergence of the COVID-19 pandemic has increased the need for rigorous infection control including effective decontamination of potential fomites in the healthcare environment. This article aims to review the evidence for the role of textiles in the transmission of infection, outline current procedures for laundering healthcare textiles and review studies evaluating the decontamination efficacy of domestic and industrial laundering.

METHODOLOGY

Pubmed, Google Scholar and Web of Science were searched for publications pertaining to the survival and transmission of microorganisms on textiles with a particular focus on the healthcare environment.

RESULTS

A number of studies indicate that microorganisms survive on textiles for extended periods of time and can transfer on to skin and other surfaces suggesting it is biologically plausible that HCAIs and other infectious diseases can be transmitted directly through contact with contaminated textiles. Accordingly, there are a number of case studies that link small outbreaks with inadequate laundering or infection control processes surrounding healthcare laundry. Studies have also demonstrated the survival of potential pathogens during laundering of healthcare textiles, which may increase the risk of infection supporting the data published on specific outbreak case studies.

CONCLUSIONS

There are no large-scale epidemiological studies demonstrating a direct link between HCAIs and contaminated textiles yet evidence of outbreaks from published case studies should not be disregarded. Adequate microbial decontamination of linen and infection control procedures during laundering are required to minimise the risk of infection from healthcare textiles. Domestic laundering of healthcare worker uniforms is a particular concern due to the lack of control and monitoring of decontamination, offering a route for potential pathogens to enter the clinical environment. Industrial laundering of healthcare worker uniforms provides greater assurances of adequate decontamination compared to domestic laundering, due to the ability to monitor laundering parameters; this is of particular importance during the COVID-19 pandemic to minimise any risk of SARS-CoV-2 transmission.

Molecular typing of methicillin-resistant Staphylococcus aureus: Comparison of PCR-based open reading frame typing, multilocus sequence typing, and Staphylococcus protein A gene typing

The recently developed PCR-based open reading frame typing (POT) method is a useful molecular typing tool. Here, we evaluated the performance of POT for molecular typing of methicillin-resistant Staphylococcus aureus (MRSA) isolates and compared its performance to those of multilocus sequence typing (MLST) and Staphylococcus protein A gene typing (spa typing). Thirty-seven MRSA isolates were collected between July 2012 and May 2015. MLST, spa typing, and POT were performed, and their discriminatory powers were evaluated using Simpson's index analysis. The MRSA isolates were classified into 11, 18, and 33 types by MLST, spa typing, and POT, respectively. The predominant strains identified by MLST, spa typing, and POT were ST8 and ST764, t002, and 93-191-127, respectively. The discriminatory power of MLST, spa typing, and POT was 0.853, 0.875, and 0.992, respectively, indicating that POT had the highest discriminatory power. Moreover, the results of MLST and spa were available after 2 days, whereas that of POT was available in 5 h. Furthermore, POT is rapid and easy to perform and interpret. Therefore, POT is a superior molecular typing tool for monitoring nosocomial transmission of MRSA.

Healthcare Personnel Attire and Devices as Fomites: A Systematic Review

BACKGROUND Transmission of pathogens within the hospital environment remains a hazard for hospitalized patients. Healthcare personnel clothing and devices carried by them may harbor pathogens and contribute to the risk of pathogen transmission. OBJECTIVE To examine bacterial contamination of healthcare personnel attire and commonly used devices. METHODS Systematic review. RESULTS Of 1,175 studies screened, 72 individual studies assessed contamination of a variety of items, including white coats, neckties, stethoscopes, and mobile electronic devices, with varied pathogens including Staphylococcus aureus, including methicillin-resistant S. aureus, gram-negative rods, and enterococci. Contamination rates varied significantly across studies and by device but in general ranged from 0 to 32% for methicillin-resistant S. aureus and gram-negative rods. Enterococcus was a less common contaminant. Few studies explicitly evaluated for the presence of Clostridium difficile. Sampling and microbiologic techniques varied significantly across studies. Four studies evaluated for possible connection between healthcare personnel contaminants and clinical isolates with no unequivocally direct link identified. CONCLUSIONS Further studies to explore the relationship between healthcare personnel attire and devices and clinical infection are needed. Infect Control Hosp Epidemiol 2016;1-7.

Antibiotic Resistance Profiling of Staphylococcus aureus Isolated from Clinical Specimens in a Tertiary Hospital from 2010 to 2012

MRSA infection can affect a wide array of individuals that may lead to treatment failure. Also, the infection has the potential to spread from one area to another particularly health care facilities or communities eventually causing minor outbreaks. With this premise, the study aimed to describe MRSA infections using the hospital-based data of a tertiary hospital in Bacolod City, Philippines, from 2010 to 2012. Specifically, this study aimed to evaluate the antimicrobial resistance of S. aureus isolated from clinical specimens and to put emphasis on the prevalence of MRSA and Inducible Clindamycin Resistance. A total of 94 cases from 2010 to 2012 were diagnosed to have S. aureus infection using conventional bacteriologic methods. From these cases, 38 (40.6%) were identified as MRSA and 37 (39.4%) were inducible clindamycin resistant. Wounds and abscesses were considered to be the most common specimens with MRSA infections having 71.05% while blood was the least with 5.3%. For drug susceptibility, out of the 94 S. aureus cases, including MRSA, 100% were susceptible to linezolid making it the drug of choice for this study. It was then followed by tetracycline having a mean susceptibility of 95%;, while penicillin G was ineffective with 94 cases having 0% susceptibility.

Bacterial contamination of healthcare workers' uniforms: a randomized controlled trial of antimicrobial scrubs

BACKGROUND

Healthcare workers' (HCWs) uniforms become contaminated with bacteria during normal use, and this may contribute to hospital-acquired infections. Antimicrobial uniforms are currently marketed as a means of reducing this contamination.

OBJECTIVE

To compare the extent of bacterial contamination of uniforms and skin when HCWs wear 1 of 2 antimicrobial scrubs or standard scrubs.

DESIGN

Prospective, randomized, controlled trial.

SETTING

University-affiliated, public safety net hospital

PARTICIPANTS

Hospitalist physicians, nurse practitioners, physician assistants, housestaff, and nurses (total N = 105) working on internal medicine units.

INTERVENTION

Subjects were randomized to wear standard scrubs or 1 of 2 antimicrobial scrubs.

MEASUREMENTS

Bacterial colony counts in cultures taken from the HCWs' scrubs and wrists after an 8-hour workday.

RESULTS

The median (interquartile range) total colony counts was 99 (66-182) for standard scrubs, 137 (84-289) for antimicrobial scrub type A, and 138 (62-274) for antimicrobial scrub type B (P = 0.36). Colony counts from participants' wrists were 16 (5-40) when they wore standard scrubs and 23 (4-42) and 15 (6-54) when they wore antimicrobial scrubs A and B, respectively (P = 0.92). Resistant organisms were cultured from 3 HCWs (4.3%) randomized to antimicrobial scrubs and none randomized to standard scrubs (P = 0.55). Six participants (5.7%) reported side effects to wearing scrubs, all of whom wore antimicrobial scrubs (P = 0.18).

CONCLUSIONS

We found no evidence that either antimicrobial scrub product decreased bacterial contamination of HCWs' uniforms or skin after an 8-hour workday.

Vestuário de profissionais de saúde como potenciais reservatórios de microrganismos: uma revisão integrativa

Objetivou-se identificar na literatura, artigos sobre a ocorrência de contaminação por microrganismos, em jalecos, aventais e uniformes dos profissionais de saúde, e a similaridade com aqueles associados às Infecções Relacionadas à Assistência à Saúde, considerando o perfil de resistência aos antimicrobianos. Realizou-se busca por artigos nas seguintes bases de dados: MEDLINE, LILACS e SCOPUS, publicados entre 2000 e 2010. Foram selecionados nove artigos. Os estudos evidenciaram a contaminação dos jalecos, aventais e uniformes. Nos estudos analisados, verificou-se a presença de bactérias, principalmente, nos bolsos, punhos e região abdominal. Quanto ao perfil de sensibilidade, verificou-se recuperação de Staphylococcus aureus meticilina resistente, seguidos dos Gram negativos resistentes aos antimicrobianos. Identificou-se semelhança entre as cepas isoladas no vestuário dos profissionais de saúde e aquelas relacionadas à ocorrência de infecções. Assim, jalecos, aventais e uniformes devem ser considerados na cadeia de disseminação de microrganismos resistentes.

Newly cleaned physician uniforms and infrequently washed white coats have similar rates of bacterial contamination after an 8-hour workday: a randomized controlled trial

BACKGROUND

Governmental agencies in the United Kingdom and Scotland have recently instituted guidelines banning physicians' white coats and the wearing of long-sleeved garments to decrease nosocomial transmission of bacteria.

OBJECTIVE

Our aim was to compare the degree of bacterial and methicillin-resistant Staphylococcus aureus contamination of physicians' white coats with that of newly laundered, standardized short-sleeved uniforms after an 8-hour workday and to determine the rate at which bacterial contamination of the uniform ensued.

DESIGN

The design was a prospective, randomized controlled trial.

SETTING

The setting was a university-affiliated public safety-net hospital.

PARTICIPANTS

One hundred residents and hospitalists on an internal medicine service participated.

INTERVENTION

Subjects wore either a physician's white coat or a newly laundered short-sleeved uniform.

MEASUREMENTS

Bacterial colony count and the frequency with which methicillin-resistant Staphylococcus aureus was cultured from both garments over time were measured.

RESULTS

No statistically significant differences were found in bacterial or methicillin-resistant Staphylococcus aureus contamination of physicians' white coats compared with newly laundered short-sleeved uniforms or in contamination of the skin at the wrists of physicians wearing either garment. Colony counts of newly laundered uniforms were essentially zero, but after 3 hours of wear they were nearly 50% of those counted at 8 hours.

CONCLUSIONS

Bacterial contamination occurs within hours after donning newly laundered short-sleeved uniforms. After 8 hours of wear, no difference was observed in the degree of contamination of uniforms versus infrequently laundered white coats. Our data do not support discarding long-sleeved white coats for short-sleeved uniforms that are changed on a daily basis.

Aspectos de biossegurança relacionados ao uso do jaleco pelos profissionais de saúde: uma revisão da literatura

O estudo objetivou analisar a literatura publicada a respeito dos aspectos da biossegurança relacionados ao uso do jaleco pelos profissionais da saúde. Trata-se de uma revisão narrativa da literatura publicada no período de 1991 a 2008. Utilizou-se as bases de dados MEDLINE, LILACS e SciELO, sendo selecionados 22 artigos que foram agrupados para análise considerando os enfoques priorizados em: infecções cruzadas causadas por jalecos; jalecos contaminados; flora bacteriana em jalecos dos profissionais de saúde. O jaleco foi abordado como fonte de contaminação e como equipamento de proteção individual na prevenção das infecções. Portanto, são necessárias campanhas educativas no sentido de orientar os profissionais de saúde sobre o uso de jaleco.

Bacterial contamination of health care workers' white coats

BACKGROUND

Patient-to-patient transmission of nosocomial pathogens has been linked to transient colonization of health care workers, and studies have suggested that contamination of health care workers' clothing, including white coats, may be a vector for this transmission.

METHODS

We performed a cross-sectional study involving attendees of medical and surgical grand rounds at a large teaching hospital to investigate the prevalence of contamination of white coats with important nosocomial pathogens, such as methicillin-sensitive Stapylococcus aureus, methicillin-resistant S aureus (MRSA), and vancomycin-resistant enterococci (VRE). Each participant completed a brief survey and cultured his or her white coat using a moistened culture swab on lapels, pockets, and cuffs.

RESULTS

Among the 149 grand rounds attendees' white coats, 34 (23%) were contaminated with S aureus, of which 6 (18%) were MRSA. None of the coats was contaminated with VRE. S aureus contamination was more prevalent in residents, those working in inpatient settings, and those who saw an inpatient that day.

CONCLUSION

This study suggests that a large proportion of health care workers' white coats may be contaminated with S aureus, including MRSA. White coats may be an important vector for patient-to-patient transmission of S aureus.

Molecular analysis of Clostridium difficile at a university teaching hospital in Japan: a shift in the predominant type over a five-year period

Clostridium difficile isolates recovered from patients admitted to a teaching hospital in Japan over a 5-year period were analyzed. Two molecular typing systems, PCR ribotyping and pulsed-field gel electrophoresis (PFGE) analysis, were used. Twenty-six PCR ribotypes were found among the 148 isolates. The predominant type at our hospital appeared to shift during the study period, from PCR ribotype a in 2000 (15/33, 45%) to PCR ribotype f in 2004 (18/28, 64%). By using PFGE with thiourea added to both the gel and running buffer, all 148 Clostridium difficile isolates were successfully classified into 37 types and 61 subtypes. The PCR ribotype f isolates were further classified into four types and 11 subtypes by PFGE. The PFGE patterns of the 11 subtypes differed from each other by only 1 to 4 bands, suggesting that these differences might reflect genetic changes during patient-to-patient transmission over the 5-year period analyzed, and that PCR ribotype f isolates might be outbreak-related. In addition, the PCR ribotype f was identical to the PCR ribotype designated smz, which is reported to have caused multiple outbreaks in Japan. These results confirmed that PCR ribotype f (type smz) has specific virulence or survival factors that make it more likely to cause nosocomial outbreaks at Japanese hospitals. PCR ribotype 027, which has been reported to have caused recent outbreaks in North America and Europe, was recovered from one patient in this study; however, this strain was community-acquired. Our findings emphasize the importance of monitoring specific strains to control and prevent nosocomial infection.

Methicillin-resistant Staphylococcus aureus colonization in veterinary personnel

TOC Summary: Prevalence of colonization was 6.5%, and employment within a large-animal practice was a significant risk factor.

Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from nares of 27/417 (6.5%) attendees at an international veterinary conference: 23/345 (7.0%) veterinarians, 4/34 (12.0%) technicians, and 0/38 others. Colonization was more common for large-animal (15/96, 15.6%) than small-animal personnel (12/271, 4.4%) or those with no animal patient contact (0/50) (p<0.001). Large-animal practice was the only variable significantly associated with colonization (odds ratio 2.9; 95% confidence interval 1.2–6.6). Pulsed-field gel electrophoresis identified 2 predominant clones with similar distribution among veterinarians as previously reported for horses and companion animals. Canadian epidemic MRSA-2 (CMRSA) was isolated from 11 small-animal and 2 large-animal personnel from the United States (n = 12) and Germany (n = 1). In contrast, CMRSA-5 was isolated exclusively from large-animal personnel (p<0.001) in the United States (n = 10), United Kingdom (n = 2), and Denmark (n = 1). MRSA colonization may be an occupational risk for veterinary professionals.

Analysis of Antimicrobial Resistance for Staphylococcus aureus Strains by WHONET 5: Microbiology Laboratory Database Software

OBJECTIVES

To analyze our hospital laboratory microbiological data by using WHONET 5-Microbiology laboratory database software-, and to acquire information about antimicrobial resistance of Staphylococcus aureus strains among every ward.

MATERIALS AND METHODS

The database of Staphylococcus aureus strains had been brought to our hospital microbiology laboratory from every ward in our hospital from September 2001 till December 2002. Analysis was performed under the condition as one isolate per one patient. Starting of "resistance profile" analysis in WHONET 5 and analyzing the microbiological laboratory testing reports for every ward. We chose Oxacillin, Levofloxacin, Erythromycin and Gentamicin as the antimicrobials that need to be investigated for resistance. We evaluated the monthly transition of resistance ratios with regard to the specific wards that have the moving lines of inpatients in order to verify the hypothesis that resistant strains may be carried from ward to ward along the moving lines of inpatients.

RESULTS

The data of 2,113 Staphylococcus aureus strains were accumulated and analyzed. Overall Oxacillin resistance ratio in our hospital was 65.7%. The ward of the smallest Oxacillin resistance ratio was Pediatrics/Ophthalmology ward. The ratios of Oxacillin resistant were varied as from 67.9% to 96.7% regardless the categories of wards such as internal medicine or surgery. Multi-resistant MRSA strains were overwhelmingly dominant in the wards of surgery. The ratios of the Gentamicin sensitive strains that were resistant to Oxacillin were high over the every ward. The moving lines of inpatients existed between ICU/CCU ward and three rear wards. Two rear wards whose Oxacillin resistance changes were reflected to those of ICU/CCU, but one rear ward was not.

CONCLUSION

Variation of resistant degree among wards were very obvious and large. We could survey the wards where patient-to-patient transmission of resistant organisms might occur along the moving lines of inpatients. WHONET 5 will be recognized as an analysis and surveillance tool for every infection control team to survey the suspicious wards.