Prevalence of methicillin-resistant Staphylococcus aureus colonisation in Tasmanian rural hospitals

Abstract

A point prevalence study was performed to determine the methicillin-resistant Staphylococcus aureus (MRSA) nasal colonisation rates in Tasmanian rural hospital inpatients. Nasal swabs were performed on all Tasmanian rural hospital inpatients hospitalised for more than 48 h before collection. A single swab was collected from both anterior nares and cultured for MRSA. Molecular typing was performed on all MRSA isolated. Demographic and clinical data was collected for each study participant. Data was analysed using the statistical software program SPSS. A total of 185 patients from 14 rural hospitals were included in the study. MRSA was isolated from 13 (7%) patients. Significant differences in MRSA prevalence were found between regions (P < 0.05) and between hospitals (P < 0.05). In the northern region of Tasmania, 11% of rural inpatients were colonised with MRSA, compared with 3 and 0% of rural inpatients in the State’s north-west and southern regions, respectively. The presence of an indwelling urinary catheter was associated with a higher risk of MRSA nasal colonisation (P = 0.066). Patient age, gender and duration of hospital admission before the swab was collected were not identified as significant risk factors for MRSA nasal colonisation. Twelve of the 13 MRSA (92%) isolated were characterised as ST22-MRSA-IV (EMRSA-15). There is a higher prevalence of MRSA nasal colonisation in rural hospital inpatients in the northern region of Tasmania compared with other Tasmanian regions. ST22-MRSA-IV may be endemic in at least one northern Tasmanian rural hospital. This information may have implications for future strategies designed to minimise the prevalence and transmission of MRSA in Tasmania.