MRSA can spread slowly but surely in households

Research Activities, November 2010, No. 363

Methicillin-resistant Staphylococcus aureus (MRSA) was once a bacterium found only in health care settings, but more often is now being found in communities. In households, the bacteria can spread from family member to family member through casual contact.

Researchers at the University of Pennsylvania School of Medicine identified eight individuals with MRSA infections and asked all family members of these patients to swab their noses, armpits, throats, groins, and perineum every 2 weeks for 3 months and send the samples to a laboratory to be tested for MRSA colonies. Among the eight MRSA-infected patients, it took an average of 33 days to clear MRSA colonization. Among the seven family members, three (43 percent) were also colonized with MRSA. One was found to be positive for MRSA colonies at the first test; two others became colonized after they were enrolled in the study. Among these three patients, it took an average of 54 days for MRSA to clear. Having a MRSA-colonized family member was associated with a longer duration of MRSA colonization in the individual with the original MRSA infection.

These results suggest the colonization for community-acquired MRSA occurs within households. Further, when a second family member becomes colonized with MRSA, the duration of MRSA colonization increases for the patient who originally brought the MRSA into the home. This study was funded in part by the Agency for Healthcare Research and Quality (H16946).

See "The impact of household transmission on duration of outpatient colonization with methicillin-resistant Staphylococcus aureus," by Ebbing Lautenbach, M.D., M.P.H., M.S.C.E., Pam Tolomeo, M.P.H., C.C.R.P., Irving Nachamkin, Dr.P.H., M.P.H., and others in the May 2010 Epidemiology and Infection 138(5), pp. 683-685.

Current as of November 2010
Internet Citation: MRSA can spread slowly but surely in households: Research Activities, November 2010, No. 363. November 2010. Agency for Healthcare Research and Quality, Rockville, MD. http://archive.ahrq.gov/news/newsletters/research-activities/nov10/1110RA5.html