Environmental survey of methicillin-resistant staphylococcus in a hospital in Japan

We examined the hospital-wide incidence of methicillin-resistant Staphylococcus contamination in a hospital environment to predict the risk of the nosocomial spread of infection. Samples were also taken different surfaces and medical equipment in a general hospital ward and a staff station. The isolates were identified bacterial strains and analyzed by PCR for detection of the mecA gene and staphylococcal cassette chromosome mec（SCCmec）types（I-V）. Overall, out of 146 isolates that were screened, 15.7% of the samples in the hospital wards were contaminated with Staphylococcus aureus and 74.7% were isolated with coagulase-negative Staphylococci（CNS）. The methicillin-resistant mecA gene was detected in all oxacillin-resistant S. aureus, and 89% of oxacillin-resistant CNS was identified as methicillin-resistant S. aureus （MRSA）and MRCNS respectively. All S. aureus and CNS from the hospital wards with MRSA patients were detected as MRSA and MRCNS. A widespread distribution of MRSA and MRCNS was detected in the Cuff. The majority of the MRSA and MRCNS isolates in this study were SCCmec type V, which are a community-acquired infection type. The increased incidence and prevalence of community-acquired MRSA and MRCNS, as well as hospital-acquired MRSA, should be recognized as serious healthcare problems.