Contrasting methicillin-resistant Staphylococcus aureus colonization in Veterans Affairs and community nursing homes.
OBJECTIVE
To compare the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) nares colonization, the patterns of MRSA acquisition, and the risk for subsequent MRSA infection between a hospital-based, Department of Veterans Affairs (VA) nursing home care unit (NHCU) and community-based nursing homes.


METHODS
In this prospective study, 148 residents of three community nursing homes and 55 residents of a VA NHCU had their anterior nares swabbed; repeat cultures were obtained from hospitalized patients and/or individuals colonized with MRSA. Subjects were followed up prospectively for 1 year to note hospitalizations and the development of MRSA infections.


RESULTS
The prevalence of MRSA colonization was significantly higher in the VA NHCU than in the community nursing homes (mean +/- SD 30.3% +/- 11% versus 9.9% +/- 4%). The rate of MRSA nares colonization was similar in the two settings. Acquisition of MRSA took place in both the long-term care facilities and hospitals, with 23.8% of incident cases occurring during a hospitalization. Only 3 of the 27 individuals colonized at baseline developed an MRSA infection. A trend toward an increased rate of infection was seen in colonized individuals residing in the community nursing homes versus those in the VA NHCU (relative risk 4.67; 95% Cl 0.55 to 39.9). Forty-seven percent of the 55 subjects hospitalized were colonized at some point during the study. In contrast to residents of the VA NHCU, MRSA colonization in the community facilities was a marker for high mortality.


CONCLUSIONS
Outcomes from colonization may be different in the VA NHCU population and the community nursing home population.
Mulhausen
P L
PL
Geriatric Research, Education, and Clinical Center, VAMC Durham, North Carolina, USA.
Harrell
L J
LJ
Weinberger
M
M
Kochersberger
G G
GG
Feussner
J R
JR
D000368:Aged; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000382:microbiology; D003428:Cross Infection / Q000382:microbiology; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006787:Hospitals, Veterans; D006801:Humans; D015994:Incidence; D008134:Long-Term Care; D008297:Male; D016106:Methicillin Resistance; D009666:Nose / Q000382:microbiology*; D009735:Nursing Homes; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D015996:Survival Rate