Risk Factors For MRSA Colonization Research Articles

P18 Prevalence and risk factors for nasal colonization with MRSA among children attending immunization in Port Harcourt, Nigeria

Background Staphylococcus aureus is a bacterial agent commonly found on the skin and anterior nares of healthy individuals. There has been an increase in the carriage of MRSA globally. Nasal MRSA colonization is a public health problem because it is a significant risk factor for staphylococcal infection. This study explores the prevalence, antibiotic susceptibility profile and risk factors for nasal colonization of healthy children under 5 years old attending immunization.MethodsNasal swabs were collected from 176 healthy children 0–60 months old, attending routine immunization in Port Harcourt. Questionnaires covering demographic information and potential risk factors were administered to caregivers of the children. Collected samples were tested for the presence of MSSA and MRSA. Antibiotic susceptibility testing was carried out on all MSSA and MRSA samples.ResultsThe prevalence of MSSA and MRSA were 10/176 (5.68%) and 48/176 (27.3%), respectively. The MDR rate among the 58 S. aureus samples was 53/58 (91.38%). Children who had an ear infection in the preceding 1 month were at a higher risk of being colonized with MRSA at P = 0.048 (95% CI). There was also a significant association P = 0.036 (95% CI) between the educational status of mother and nasal colonization, with higher educational status reducing the chances of association.ConclusionsThere is a rising prevalence of MRSA colonization and MDR strains. A history of ear infections and a poor level of education of the mother were identified as significant risk factors for MRSA colonization.Table 1.Association between potential risk factors and MRSA carriageFactorsMRSAχ2 P valuepositivenegativeHospitalization0.3770.539f Yes01 No48127Hospital visit0.1400.708 Yes511 No43117RTI0.8630.353 Yes2474 No2454Ear infection4.8600.048* f Yes42 No44126Antibiotic use1.3750.241 Yes935 No3993Family health worker0.3040.582 Yes510 No43118Smoker1.6380.243f Yes213 No46114*Significant at 95%; fFisher's exact test.

Risk factors for nosocomial methicillin resistant Staphylococcus aureus (MRSA) colonization in a neonatal intensive care unit: A Case-control study

To determine risk factors for MRSA colonization in a Level IV Neonatal Intensive Care Unit (NICU) independent of length of stay and gestational age in the context of a persistently circulating MRSA clone. Retrospective matched case-control study. Level IV NICU PATIENTS: Infants admitted between April 4,2017- March 31,2018. Based on weekly surveillance cultures, infants who acquired MRSA were matched 1:1 with MRSA-negative control infants by duration of exposure (length of stay) and gestational age to determine risk factors for acquisition. Fifty case infants were matched with controls. Isolates from 45 of the 50 cases were mupirocin-resistant and related by pulse-field gel electrophoresis. On matched univariable analysis, the following were significantly associated with a risk for MRSA acquisition: 1.Bed location in the acute area(P = 0.03), 2.Requirement of any level of respiratory support during the week prior to MRSA detection(P = 0.04), 3.Higher ATP pass rate (a measure of effectiveness of cleaning) during the week of and week prior(P = 0.01), 4.Higher MRSA colonization pressure during the week of and week prior(P< 0.0001), 5.Not having a hearing test during the time between the previous negative culture and MRSA acquisition(P = 0.01). A multivariable conditional logistic regression model (that excluded ATP pass rate) found that only colonization pressure was associated with acquisition of MRSA colonization. In an outbreak setting, MRSA colonization pressure is significantly associated with MRSA acquisition in the NICU independent of length of stay and gestational age.

Prevalence of MRSA colonisation amongst patients undergoing elective orthopaedic implant surgery at North Bristol NHS Trust

Introduction: National guidelines recommend MRSA screening of all patients before elective orthopaedic implant procedures (EOIP) as a measure to reduce risk of MRSA surgical site infection (SSI). With low prevalence of MRSA in UK currently, this universal approach of screening all EOIP patients may be unnecessary. Objectives To determine MRSA colonisation rate of EOIP patients pre surgery and number of MRSA-positive patients developing surgical site infection (SSI) within 30 days. Methods: North Bristol NHS Trust is the largest Orthopaedic unit in Southwest England. It performs over 6000 elective Orthopaedic operations annually, including 2000 hip and knee joint replacements. All major elective cases are reviewed in a pre-operative assessment clinic where MRSA screening, amongst other tests, is performed. The pathology IT system was interrogated to identify data on patients screened for MRSA in the orthopaedic pre-assessment clinic from 1st January to 31st March 2019. Routinely collected SSI data was reviewed for details of any SSI in these patients. Results: 439 patients were screened in the pre-operative clinic. 4/439 patients (0.9%) had positive screens. Applying national MRSA screening criteria, 2/4 patients had recognised risk factors for MRSA colonisation (including one patient previously MRSA colonised), and 2/4 did not. All 4 patients were decolonised pre-surgery and none developed SSI. No patient developed MRSA SSI. Conclusions: Approximately 1%, of patients attending for EOIP are colonised with MRSA in this Trust. No patient developed MRSA SSI in the 3month period. There may be potential to rationalise the approach to MRSA screening in EOIP patients.

587. Risk Factors for Nosocomial Methicillin-Resistant Staphylococcus aureus (MRSA) Colonization in a Neonatal Intensive Care Unit (NICU): A Case–Control Study

Background Staphylococcus aureus (SA) is a leading cause of nosocomial infection in NICUs. Colonization is a prerequisite for most SA infections. Previously recognized risk factors for colonization include the length of stay (LOS), multiple gestation, low birth weight, Caesarean delivery and multibed location. The objective of this study was to determine risk factors for MRSA colonization in a Level IV NICU independent of LOS and gestational age (GA) in the context of a circulating MRSA clone.MethodsWeekly MRSA colonization cultures were performed from April 2017 through March 2018. Case–control study. Cases: Infants with newly acquired MRSA colonization and at least one previous negative culture. Controls: Infants with negative surveillance cultures, matched 1:1 with cases by GA and LOS. Factors compared: (a) neonatal demographics; (b) maternal factors; (c) neonatal factors since admission including antimicrobial therapy; (d) neonatal factors during the week prior to MRSA acquisition, including bed location, number of location changes, presence of central line, respiratory support, NICU census, ATP surface bioburden testing pass rate, MRSA colonization pressure.Results50 case infants were matched with controls. Forty-five of the 50 isolates were mupirocin-resistant and related by pulse-field gel electrophoresis On matched univariable analysis, the following were significantly associated with a risk for MRSA acquisition: (1) Bed location in the acute area (P = 0.03), (2) The requirement of any level of respiratory support during the week prior to MRSA detection (P = 0.04), (3) Higher ATP pass rate during the week of and week prior (P = 0.01), (4) Higher MRSA colonization pressure during the prior week (P = 0.002), (5) Not having a hearing test during the time between the previous negative culture and MRSA acquisition (P = 0.01). A multivariable conditional logistic regression model (that excluded ATP pass rate) found that only colonization pressure was associated with acquisition of MRSA colonization.ConclusionIndependent of LOS and GA, MRSA colonization pressure, ATP pass rate and higher patient acuity, reflected by location within the acute area and requiring respiratory support, are significantly associated with MRSA acquisition in the NICU; only colonization pressure remained associated in a multivariable model.Disclosures All authors: No reported disclosures.

MRSA prevalence among patient transport staff in Hamburg.

Introduction: Patient transport employees frequently come into contact with multidrug-resistant organisms (MDROs) and therefore are at a greater risk of infection than the general population. These pathogens pose a significant challenge for employees of patient transport services since they can spread over long distances through patient transfers. To date, little is known about the occupational risk of MRSA infection in patient transport settings.Methods: A cross-sectional study was conducted to investigate the prevalence of MRSA in patient transport personnel, including taxi drivers, as well as the potential risk factors for MRSA colonization. For screening, nasal swabs were taken. When an individual was tested positive, a control swab was taken; if this confirmed a positive result, decolonization measures were offered. A molecular biological examination of the MRSA samples was performed. Results: A total of 222 patient transport employees were screened and 7 employees tested positive, putting the MRSA prevalence at 3.2% (95% CI 1.4–6.5). Significant risk factors among patient transport staff (PTS) for testing positive were the use of antibiotics (OR 11.9; 95% CI 1.8–78.4) and hospital admission (OR 6.9; 95% CI 1.1–45.9). MRSA swabs were also performed on a total of 102 taxi drivers who provide patient transport services. The MRSA prevalence was 0.98 (95% CI <0.01–5.9). Significant group differences between PTS and taxi drivers, with respect to potential risk factors for MRSA colonization, were identified as inpatient treatment (p=0.09), chronic respiratory illnesses (p=0.01), and knowingly transporting patients/passengers with MRSA (p=0.03).Conclusion: This study is the first to make data on the MRSA risk of patient transport employees in Hamburg available. The prevalence data are low in all areas and indicate a somewhat low risk of infection. A good infection control at the facilities is highly recommendable and the employees should acquire in-depth knowledge of infection prevention to improve compliance with personal protective measures.

MRSA Prevalence and Risk Factors among Health Personnel and Residents in Nursing Homes in Hamburg, Germany - A Cross-Sectional Study.

IntroductionThe increase of multidrug-resistant organisms in hospitals causes problems in nursing homes. Staff in geriatric nursing homes are at greater risk of MRSA colonisation. The aim of the study was to describe the occupational exposure to MRSA among health personnel in geriatric nursing.MethodsA point prevalence survey was conducted among health personnel and residents of geriatric nursing homes within the greater Hamburg district. Nasal swabs and, where relevant, wound swabs were collected for the screening survey. Risk factors for MRSA colonisation were identified by means of a questionnaire and using the files held on the residents. Where tests on nursing staff were positive, a control swab was taken; when the results were confirmed positive, decolonisation was performed. The responsible general practitioners were notified of positive MRSA findings among residents. A molecular biological examination of the MRSA samples was performed.ResultsA total of 19 institutions participated in the study. Nasal swabs were taken from 759 nursing staff and 422 residents. Prevalence of MRSA was 1.6% among staff and 5.5% among residents. MRSA colonisation among health personnel indicated a correlation with male gender (OR 4.5, 95% CI 1.4–14.1). Among the residents, chronic skin diseases (OR 3.2, 95% CI 1.0–10.3) and indwelling devices (OR 3.2, 95% CI 1.2–8.1) were identified as risk factors. No link between MRSA in residents and in health personnel could be established.ConclusionThe number of MRSA colonisations among nursing staff and residents of geriatric nursing homes in Hamburg was rather low at 1.6% and 5.5% respectively and equates to the results of other surveys in non-outbreak scenarios.

Staphylococcus aureus: Screening for Nasal Carriers in a Community Setting with Special Reference to MRSA.

Introduction. Emergence of MRSA infections among previously healthy persons in community settings (without exposure to health care facilities) has been noted recently. MRSA infections are now classified as health care-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) infections. Its colonization is an important risk factor for subsequent MRSA infection. Aims and Objectives. The aim was to screen patients and health care workers for staphylococcal carriage, identify risk factors for MRSA colonization, and determine the sensitivity pattern. Materials and Methods. A total of 200 subjects were screened for nasal carriage after obtaining verbal consent. These were both healthy subjects attending various outpatient departments and health care workers. Specimens were collected from the anterior nares using premoistened sterile cotton swabs and inoculated onto blood agar and mannitol salt agar and incubated at 37°C for 24–48 h. Results. Staphylococcus aureus colonisation was found to be 12% (n = 24). MRSA was identified in 5% (n = 10) which represents 41.66% of SA. A total of 10 strains of MRSA were isolated from 200 subjects, giving an overall positivity rate of 5%. Discussion. Staphylococcal colonization was found to be 12% (MRSA 5%). Fluoroquinolone resistance was remarkable whereas all strains were sensitive to vancomycin, teicoplanin, linezolid, quinupristin-dalfopristin.

Prevalence of and risk factors for MRSA colonization in HIV-positive outpatients in Singapore

BackgroundWhilst there have been studies on the risks and outcomes of MRSA colonization and infections in HIV-positive patients, local data is limited on the risk factors for MRSA colonization among these patients. We undertook this study in a tertiary HIV care centre to document the risk factors for colonization and to determine the prevalence of MRSA colonization among HIV-positive outpatients in Singapore.MethodsThis was a cross-sectional study in which factors associated with MRSA positivity among patients with HIV infection were evaluated. A set of standardized questionnaire and data collection forms were available to interview all recruited patients. Following the interview, trained nurses collected swabs from the anterior nares/axilla/groin (NAG), throat and peri-anal regions. Information on demographics, clinical history, laboratory results and hospitalization history were retrieved from medical records.ResultsMRSA was detected in swab cultures from at least 1 site in 15 patients (5.1%). Inclusion of throat and/or peri-anal swabs increased the sensitivity of NAG screening by 20%. Predictors for MRSA colonization among HIV-positive patients were age, history of pneumonia, lymphoma, presence of a percutaneous device within the past 12 months, history of household members hospitalized more than two times within the past 12 months, and a most recent CD4 count less than 200.ConclusionsThis study highlights that a proportion of MRSA carriers would have been undetected without multiple-site screening cultures. This study could shed insight into identifying patients at risk of MRSA colonization upon hospital visit and this may suggest that a risk factor-based approach for MRSA surveillance focusing on high risk populations could be considered.

Persistence of ST398 MRSA carriage in livestock farmers

ObjectivesA few years ago a new strain of Methicillin resistant Staphylococcus aureus, the CC398, Livestock Associated MRSA, emerged in humans. Carriage in humans is associated with intensity of livestock contact....

Prevalence and risk factors for methicillin-resistant Staphylococcus aureus colonization in a diabetic outpatient population: A prospective cohort study

Diabetes mellitus is a risk factor for methicillin-resistant Staphylococcus aureus (MRSA) colonization and infection. We attempted to determine the prevalence and risk factors for MRSA colonization in a population of outpatients with diabetes. This prospective cohort study enrolled patients with diabetes. Anterior nares cultures were obtained from patients with diabetes admitted to outpatient endocrinology and metabolism clinics, and risk factors for MRSA colonization were analyzed. Out of the 304 patients evaluated, 127 (41.9%) were colonized with S aureus and 30 (9.9%) were colonized with MRSA. Overall, 23.6% of all S aureus isolates were MRSA. In multivariate analysis, factors independently associated with an increased risk of MRSA colonization included the presence of connective tissue disease (odds ratio, 7.075; 95% confidence interval, 2.157-23.209; P = .001) and insulin therapy (odds ratio, 3.910; 95% confidence interval, 1.652-9.251; P = .002). The prevalence of MRSA colonization in our sample of diabetic outpatients was 9.9%. Independent risk factors for MRSA colonization were the presence of connective tissue disease and insulin use. A better understanding of the epidemiology and risk factors for nasal MRSA colonization in the persons with diabetes may have significant implications for the treatment and prevention of MRSA infections.

Persistence of livestock associated MRSA CC398 in humans is dependent on intensity of animal contact.

IntroductionThe presence of Livestock Associated MRSA (LA-MRSA) in humans is associated with intensity of animal contact. It is unknown whether the presence of LA-MRSA is a result of carriage or retention of MRSA-contaminated dust. We conducted a longitudinal study among 155 veal farmers in which repeated nasal and throat swabs were taken for MRSA detection. Periods with and without animal exposure were covered.MethodsRandomly, 51 veal calf farms were visited from June - December 2008. Participants were asked to fill in questionnaires (n = 155) to identify potential risk factors for MRSA colonisation. Nasal and throat swabs were repeatedly taken from each participant for approximately 2 months. Swabs were analysed for MRSA and MSSA by selective bacteriological culturing. Spa-types of the isolates were identified and a ST398 specific PCR was performed. Data were analyzed using generalized estimation equations (GEE) to allow for correlated observations within individuals.ResultsMean MRSA prevalence was 38% in farmers and 16% in family members. Presence of MRSA in farmers was strongly related to duration of animal contact and was strongly reduced in periods with absence of animal contact (−58%). Family members, especially children, were more often carriers when the farmer was a carrier (OR = 2, P<0.05).Only 7% (n = 11) of the participants appeared to be persistent carriers. A large heterogeneity in spa-types was detected, however 92.7% belonged to LA-MRSA CC398. A surprisingly high fraction of the spa-types (7.3%) did not belong to CC398.ConclusionThe presence of LA-MRSA in farmers is strongly animal-exposure related. The rapidly decreasing MRSA prevalence during absence of animal contact suggests that LA-MRSA is a poor persistent colonizer in most humans. These results are of relevance for MRSA control strategies.

Risk Factors for MRSA Colonization in the Intensive Care Unit

Risk Factors for MRSA Colonization in the Intensive Care Unit

Presence and Molecular Epidemiology of Virulence Factors in Methicillin-Resistant Staphylococcus aureus Strains Colonizing and Infecting Soldiers

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as an important cause of skin and soft-tissue infections (SSTI). The understanding of the molecular epidemiology and virulence of MRSA continues to expand. From January 2005 to December 2005, we screened soldiers for MRSA nasal colonization, administered a demographic questionnaire, and monitored them prospectively for SSTI. All MRSA isolates underwent molecular analysis, which included pulsed-filed gel electrophoresis (PFGE) and PCR for Panton-Valentine leukocidin (PVL), the arginine catabolic mobile element (ACME), and the staphylococcal cassette chromosome mec (SCCmec). Of the 3,447 soldiers screened, 134 (3.9%) had MRSA colonization. Of the 3,066 (89%) who completed the study, 39 developed culture-confirmed MRSA abscesses. Clone USA300 represented 53% of colonizing isolates but was responsible for 97% of the abscesses (P < 0.001). Unlike colonizing isolates, isolates positive for USA300, PVL, ACME, and type IV SCCmec were significantly associated with MRSA abscess isolates. As determined by multivariate analysis, risk factors for MRSA colonization were a history of SSTI and a history of hospitalization. Although various MRSA strains may colonize soldiers, USA300 is the most virulent when evaluated prospectively, and PVL, ACME, and type IV SCCmec are associated with these abscesses.

Controlling MRSA in Surgical Head&Neck Patients: What Works?

Objective Can we control MRSA incidence in head and neck cancer patients by 1) Active surveillance cultures of patients fulfilling Society for Healthcare Epidemiology of America (SHEA) &amp; Scottish Infection Standards and Strategy (SISS) guideline? 2) Cohorting these patients? 3) Restricted Health Care Workers (HCW) access? Methods Prospective case series: July 2007–January 2008. 26 preoperative head and neck cancer patients had a questionnaire filled in to identify known predictors for MRSA as suggested by SISS Group. Intervention: Preoperative nasal swabs, cohorting away from other cases, restricted access. MRSA incidence compared to that over the preceding year(Jan 2006-Jan 2007). Results 26 eligible patients. None of them had known risk factors for MRSA. 17 patients had swabs taken pre-admission. All screened patients were non-carriers of MRSA in their nose and none of them developed MRSA infection during hospital stay. Of remaining 9 patients swabbed after admission, 3 developed MRSA during hospital stay. The incidence of MRSA was 11.5% (3/26) during study period, compared to 28.5% (24/84) the year before implementing these interventions. Conclusions Head and neck cancer patients do not have increased risk factors for MRSA colonization and their active surveillance cultures are unlikely to influence MRSA incidence. Cohorting these patients with restricted HCW access decreased the MRSA rate at our centre.