Abstract
Aerobic bacteria were isolated from cultures of the pharyngeal swabs obtained from patients at our facilities and the isolation rates of total Staphylococcus aureus (total SA) and methicillinresistant SA (MRSA) among the patients were investigated for a period of 7 years from 1999. The swabs were taken regularly once a year in late spring with 79-94 subjects each time. A complementary examination was carried out in late autumn for new patients and for follow-up of MRSA-posi-tive cases. The mean frequency of total SA- and MRSA-positive patients was 38.2+/-11.8% and 11.1+/-4.0%, respectively, throughout the 7 years and the MRSA/total SA ratio was 28.9%. MRSA isolation rate was compared to the origin of the patients moved to our facilities. The rate was significantly higher among patients who came to our facilities directly from hospitals than among those who came from other facilities or their own home (22.9+/-7.1% vs 6.7+/-1.9 and 4.2+/-4.8%). The isolation rate of total SA was also significantly higher in patients coming from hospitals. During the 7-year period, 90 patients underwent examination two or more times. Among the 76 patients negative for MRSA at the first examination, 12 were positive for MRSA at a later examination. All 12 patients had a history of admission to a hospital and antibiotic therapy during the 12 months prior to the later examination. Twelve of the 14 patients positive for MRSA at the first examination became negative at the second and third examinations. Correct use of antibiotics together with good management to help patients recover physical strength is important in reducing the colonization of MRSA in nursing homes.
