Meticillin-resistant Staphylococcus aureus carriage among district nurse patients and medical admissions in a UK district

Nasal Carriage Rate of Staphylococcus aureus, Its Associated Factors, and Antimicrobial Susceptibility Pattern Among Health Care Workers in Public Hospitals, Harar, Eastern Ethiopia

Background

Staphylococcus aureus is the bacteria that colonizes the nasal nares of health-care workers and serves as a reservoir for the spread of pathogen for subsequent infections, mainly Methicillin-resistant Staphylococcus aureus. However, there is a limited study conducted regarding this topic in Harar, Eastern Ethiopia.

Objective

The main objective of this study was to determine the prevalence of nasal carriage of Staphylococcus aureus, associated factors and antimicrobial susceptibility patterns among health-care workers of public hospitals in Harar, Eastern Ethiopia from May 15 to July 30, 2021.

Methods

A hospital-based cross-sectional study was conducted on 295 health-care workers. A simple random sampling technique was used to select the participant. Nasal swabs were collected and cultured at 35°C for 24hrs. S. aureus was identified using the coagulase test and catalase test. Methicillin resistance S. aureus (MRSA) was screened using a cefoxitin disc on Muller Hinton agar using the Kirby-Bauer disc diffusion method. Data were entered into EPI-Info version-7 and transferred to SPSS-20 for analysis. Factors associated with nasal carriage of Staphylococcus aureus were determined by using chi-square analysis. A p-value of less than 0.05 was considered statistically significant.

Results

The prevalence of Staphylococcus aureus in this study was 15.6% (95% CI: 11.7%, 20.3%) and methicillin-resistant Staphylococcus aureus was 11.2% (95% CI: 7.8%, 15.4%), respectively. Age (P < 0.001), work experience (p < 0.001), working unit (p < 0.02), antibiotic use within 3 months (p < 0.001), hand washing habit (p < 0.01), hand rub use (p < 0.001), living with smokers (p < 0.001), living with pets (p < 0.001) and having chronic diseases (p < 0.001) were found significantly associated with Staphylococcus aureus nasal carriage.

Conclusion

The prevalence of Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus are high in our study. The study emphasizes the need for regular surveillance among hospital staff and the environment to prevent MRSA transmission among health-care personnel.

Risk factors for infection in older adults who receive home healthcare and/or home help: A protocol for systematic review and meta-analysis

BACKGROUND

The shift towards home-based care has resulted in increased provision of home healthcare and home help to older adults. Infections acquired in older adults while receiving home care have increased too, resulting in unplanned yet avoidable hospitalizations. In recent years, several studies have reported an array of factors associated with risk of infection; however, no previous systematic review has compiled such evidence, which is important to better protect older adults. Therefore, we have outlined the work of a systematic review that aims to identify risk factors for infection in older adults receiving home healthcare and/or home help.

METHODS

Searches for relevant studies will be conducted in five databases [MEDLINE, EMBASE (Excerpta Medica Database), Web of Science Core Collection, Cinahl (Cumulative Index to Nursing & Allied Health Literature) and Sociological Abstracts]. All types of studies will be included. Exposures considered refer to medical, individual, social/behavioral and environmental risk factors for infection (outcome). Two researchers will independently go through the records generated. Eligible studies will be assessed for risk of biases using the Cochrane risk of bias assessment tool and an overall interpretation of the biases will be provided. If the data allow, a meta-analysis will be conducted. It is possible that both quantitative and qualitative studies will be identified and eligible. Therefore, for the analysis, the Joanna Briggs Institute Reviewers' Manual for mixed methods systematic reviews will be used as it allows for two or more single method reviews (e.g., one quantitative and one qualitative) to be conducted separately and then combined in a joint overarching synthesis.

RESULTS

The findings of the planned systematic review are of interest to healthcare professionals, caregivers, older adults and their families, and policy- and decisions makers in the health and social care sectors as the review will provide evidence-based data on multiple factors that influence the risk of infection among older adults receiving care in their homes.

CONCLUSION

The results could guide future policy on effective infection control in the home care sector.

Methicillin-Resistant Staphylococcus aureus Nasal Colonization Among Health Care Workers of a Tertiary Hospital in Ecuador and Associated Risk Factors

Background

Methicillin-resistant Staphylococcus aureus (MRSA) is resistant to most of the commonly used antibiotics and is therefore a public health issue. Colonization with MRSA is a risk factor for infection or transmission.

Purpose

To determine the prevalence of colonization with Staphylococcus aureus (SA) and MRSA strains in health care workers (HCWs) at a tertiary hospital in Ecuador and to determine the risk factors associated with carriage.

Methods

Out of a cohort of 3800 HCWs, 481 individuals from different hospital departments were randomly selected, and a single nasal swab was collected. Detection of SA and MRSA was carried out with the LightCycler^® MRSA Advanced Test. A questionnaire was performed that gathered demographic and occupational information of the participants to determine risk factors for MRSA colonization. Statistical analysis was performed with univariate and multivariate analysis and the R-software version 4.0.2.

Results

Colonization with SA and MRSA occurred in respectively 23.7% (95% CI, 22.7–24.6) and 5% (95% CI, 3.39–7.58) of the individuals. The multivariate analysis showed that being older in age (OD 1.09) and being male (OD 2.78) were risk factors for SA and MRSA colonization (p-value < 0.001). Previous use of antibiotics or the use of nasal ointments diminished the colonization rates of SA (24% versus 3.7% and 10.1% respectively).

Conclusion

About 20% of the HCWs who were colonized with SA were colonized with MRSA, representing a risk for nosocomial infections and hospital outbreaks. Active monitoring and a decolonization treatment of the HCWs can reduce these risks.

Individual, social, and environmental factors for infection risk among home healthcare patients: A multi-method study

There has been limited research into the individual, social, and environmental factors for infection risk among patients in the home healthcare (HHC) setting, where the infection is a leading cause of hospitalisation. The aims of this study were to (1) explore nurse perceptions of individual, social, and environmental factors for infection risk among HHC patients; and (2) identify the frequency of environmental barriers to infection prevention and control in HHC. Data were collected in 2017-2018 and included qualitative interviews with HHC nurses (n = 50) and structured observations of nurse visits to patients' homes (n = 400). Thematic analyses of interviews with nurses suggested they perceived infection risk among patients as being influenced by knowledge of and attitudes towards infection prevention and engagement in hygiene practices, receipt of support from informal caregivers and nurse interventions aimed at cultivating infection control knowledge and practices, and the home environment. Statistical analyses of observation checklists revealed nurses encountered an average of 1.7 environmental barriers upon each home visit. Frequent environmental barriers observed during visits to HHC patients included clutter (39.5%), poor lighting (38.8%), dirtiness (28.5%), and pets (17.2%). Additional research is needed to clarify inter-relationships among these factors and identify strategies for addressing each as part of a comprehensive infection control program in HHC.

Circulation of a community healthcare-associated multiply-resistant meticillin-resistant Staphylococcus aureus lineage in South Yorkshire identified by whole genome sequencing

BACKGROUND

A cluster of seven cases of skin and wound infections caused by a multiply resistant meticillin-resistant Staphylococcus aureus (MRSA) were detected in a small-town community in South Yorkshire. Initial microbiological investigations showed that all isolates belonged to a spa type observed rarely in England (t1476).

AIM

To describe the epidemiology of t1476 MRSA in South Yorkshire.

METHODS

Retrospective and prospective case ascertainment was promoted through communication with local microbiology laboratories. Public health investigation included a detailed review of clinical notes for a subset of nine cases. Genomic and phylogenetic analysis was undertaken on t1476 MRSA.

FINDINGS

Thirty-two cases of t1476 MRSA infection or colonization were identified between December 2014 and February 2018. Cases were older adults (aged 50-98 years). Healthcare exposures for a subset of nine cases indicated frequent contact with a team of district nurses, with all but one case receiving treatment on the same day as another case prior to their own diagnosis. No cases were admitted to hospital at the time of specimen collection. Despite detailed investigations, no carriers were detected among district nursing staff. A long-term carrier/super-shedder was not found. Phylogenetic analysis indicated that t1476 MRSA cases from South Yorkshire were monophyletic and distant from both MRSA of the same lineage from elsewhere in the UK (N = 15) and from publicly available sequences from Tanzania.

CONCLUSION

Genomic and epidemiological analyses indicate community-based transmission of a multiply resistant MRSA clone within South Yorkshire introduced around 2012-2013, prior to the detection of a spatial-temporal cluster associated with a distinct risk group. Surveillance data indicate continued circulation.

Patient-level factors associated with methicillin-resistant Staphylococcus aureus carriage at hospital admission: a systematic review

BACKGROUND

Selective methicillin-resistant Staphylococcus aureus (MRSA) screening programs target high-risk populations. To characterize high-risk populations, we conducted this systematic review to identify patient-level factors associated with MRSA carriage at hospital admission.

METHODS

Studies were identified in the MEDLINE (1950-2011) and EMBASE (1980-2011) databases. English studies were included if they examined adult populations and used multivariable analyses to examine patient-level factors associated with MRSA carriage at hospital admission. From each study, we abstracted details of the population, the risk factors examined, and the association between the risk factors and MRSA carriage at hospital admission.

RESULTS

Our electronic search identified 972 citations, from which we selected 27 studies meeting our inclusion criteria. The patient populations varied across the studies. Ten studies included all patients admitted to hospital, and the others were limited to specific hospital areas. MRSA detection methods also varied across studies. Ten studies obtained specimens from the nares only, whereas other studies also swabbed wounds, catheter sites, and the perianal region. Methods of MRSA diagnoses included polymerase chain reaction tests, cultures in various agar mediums, and latex agglutination tests. Patient age, gender, previous admission to hospital, and previous antibiotic use were the risk factors most commonly examined. The risk factor definition and study methods varied among studies to an extent that precluded meta-analysis.

CONCLUSION

The existing literature cannot be used to identify risk factors for MRSA colonization at the time of hospitalization. Future studies should be aware of the differences in the existing literature and aim to develop standardized risk factor definitions.

Meticillin-resistant Staphylococcus aureus carriage in UK veterinary staff and owners of infected pets: new risk groups

Meticillin-resistant Staphylococcus aureus (MRSA) nasal carriage on admission to hospital remains one of the most important risk factors for subsequent infection. Identification of high risk groups for MRSA carriage is vital for the success of infection control programmes. Veterinary staff may be one such risk group but little is known about pet owners and the role of contact with infected pets. As part of a UK-wide case-control study investigating risk factors for MRSA infection in dogs and cats between 2005 and 2008, 608 veterinary staff and pet owners in contact with 106 MRSA and 91 meticillin-susceptible S. aureus (MSSA)-infected pets were screened for S. aureus nasal carriage. Laboratory isolation and characterisation included salt broth enrichment, standard and automated microbiological tests, demonstration of the S. aureus-specific thermonuclease gene (nuc) and of mecA, and polymerase chain reaction-based lineage characterisation. MRSA carriage was 12.3% in veterinarians attending MRSA-infected animals and 7.5% in their owners. In the MSSA control group, MRSA carriage was 4.8% in veterinary staff and 0% in owners. Veterinary staff carried MRSA more frequently than owners (odds ratio: 2.33; 95% confidence interval: 1.10-4.93). All MRSA from humans and all but one animal MRSA were CC22 or CC30, typical for hospital MRSA in the UK. This study indicates for the first time an occupational risk for MRSA carriage in small animal general practitioners. Veterinary staff and owners of MRSA-infected pets are high risk groups for MRSA carriage despite not having direct hospital links. Strategies to break the cycle of MRSA infection must take these potential new reservoirs into account.

Community-associated methicillin-resistant Staphylococcus aureus infections

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been recognized for over a decade, and usually refers to MRSA identified in previously healthy individuals with no recognized MRSA risk factors. Infections range from minor skin and soft tissue infections, through to severe pneumonia and necrotizing fasciitis. This review summarizes the current data on the epidemiology and molecular features of CA-MRSA, in addition to diagnosis and therapeutic measures. We also refer to current national guidelines for the management of these infections. Areas of agreement include the important genotypic and phenotypic differences of community MRSA strains compared with hospital strains. Areas of controversy include the precise epidemiological definition of community-acquired/associated MRSA. Fortunately, true CA-MRSA can be differentiated from hospital MRSA by molecular techniques, as discussed herein. Recent interest has focused on the changing epidemiology of CA-MRSA. Worldwide, CA-MRSA is now seen outside of the initial specific population groups, and in the USA, the successful USA300 community strain is beginning to spread back into hospitals. Reasons why USA300 remains relatively uncommon in Europe are unclear. Topics timely for research include the investigation of the epidemiology of infections and evolutionary genomics.

Clinical, molecular and epidemiological description of a cluster of community-associated methicillin-resistant Staphylococcus aureus isolates from injecting drug users with bacteraemia

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is an increasing problem, predominantly in previously healthy individuals including notable risk groups such as the homeless, those who play close-contact sports, military personnel, men who have sex with men (MSM) and injecting drug users (IDUs). Over a 5-month period, four IDUs were admitted to Addenbrooke's Hospital, Cambridge, UK, with MRSA bacteraemia. All four patients presented with complex clinical features, with more than one focus of infection, and were linked epidemiologically. The atypical antibiogram of the MRSA isolates (ciprofloxacin-susceptible) prompted further characterization, both phenotypically (antibiotic resistance typing; phage typing) and genotypically (detection of toxin genes by PCR; pulsed-field gel electrophoresis (PFGE); Staphylococcal chromosome cassette (SCC) mec typing; multi-locus sequence typing (MLST)). All four isolates had similar antibiograms, were Panton-Valentine Leucocidin (PVL) toxin gene-negative, harboured SCCmec type IV and were closely related as shown by phage typing and PFGE. These isolates were representatives of a community-associated clone, ST1-MRSA-IV, known to be circulating in IDUs in the UK since 2001. This paper presents a detailed description of the clinical, microbiological and epidemiological features of a series of CA-MRSA bacteraemias in IDUs in the UK.