Diversity of Methicillin-Resistant Staphylococcus aureusStrains Isolated from Residents of 26 Nursing Homes in Orange County, California

Autor: Hudson, Lyndsey O., Reynolds, Courtney, Spratt, Brian G., Enright, Mark C., Quan, Victor, Kim, Diane, Hannah, Paul, Mikhail, Lydia, Alexander, Richard, Moore, Douglas F., Godoy, Daniel, Bishop, Cynthia J., Huang, Susan S.
Zdroj: Journal of Clinical Microbiology; November 2013, Vol. 51 Issue: 11 p3788-3795, 8p
Abstrakt: ABSTRACTNursing homes represent a unique and important methicillin-resistant Staphylococcus aureus(MRSA) reservoir. Not only are strains imported from hospitals and the community, strains can be transported back into these settings from nursing homes. Since MRSA bacteria are prevalent in nursing homes and yet relatively poorly studied in this setting, a multicenter, regional assessment of the frequency and diversity of MRSA in the nursing home reservoir was carried out and compared to that of the MRSA from hospitals in the same region. The prospective study collected MRSA from nasal swabbing of residents of 26 nursing homes in Orange County, California, and characterized each isolate by spatyping. A total of 837 MRSA isolates were collected from the nursing homes. Estimates of admission prevalence and point prevalence of MRSA were 16% and 26%, respectively. The spatype genetic diversity was heterogeneous between nursing homes and significantly higher overall (77%) than the diversity in Orange County hospitals (72%). MRSA burden in nursing homes appears largely due to importation from hospitals. As seen in Orange County hospitals, USA300 (sequence type 8 [ST8]/t008), USA100 (ST5/t002), and a USA100 variant (ST5/t242) were the dominant MRSA clones in Orange County nursing homes, representing 83% of all isolates, although the USA100 variant was predominant in nursing homes, whereas USA300 was predominant in hospitals. Control strategies tailored to the complex problem of MRSA transmission and infection in nursing homes are needed in order to minimize the impact of this unique reservoir on the overall regional MRSA burden.
Databáze: Supplemental Index