Patients with potentially deadly drug-resistant bacteria that they pick up in the hospital often carry the infection to home health care settings after hospital discharge, and transmission occurs in about one fifth of household contacts, according to a report published today.

Methicillin-resistant Staphylococcus aureus (MRSA) infections can range from boils to more severe infections of the blood, lungs and the sites of surgery. Such infections can often be treated only with expensive intravenous antibiotics.

Patients with major health problems are increasingly discharged to home health care, which creates new opportunities for the transmission of hospital-acquired MRSA, Dr. Jean-Christophe Lucet, of Bichat-Claude Bernard Hospital, Assistance Publique-Hopitaux de Paris, and colleagues note in the journal Archives of Internal Medicine.

They studied 1501 adult patients in French hospitals who were screened for MRSA before discharge to home health care between February 2003 and March 2004.

Dr. Lucet's team determined that 191 of the 1501 patients had MRSA (12.7%) before hospital discharge. Of 148 MRSA carriers who were followed up, 75 (50.6%) got rid of the infection within 1 year of hospital discharge.

Among 188 household contacts of the 191 MRSA patients, 36 (19.1%) acquired MRSA during the follow up period, although none developed an infection. People can carry the bacterium without getting sick from it.

Household contacts who were older and who played a role in providing health care for the discharged patient appeared more likely to acquire MRSA.

However, Sharing the same bed or bedroom, in contrast, was not associated with MRSA transmission. Thus, MRSA may be preferentially transmitted to contacts at high risk for hand contamination during care procedures, the investigators note.

The findings suggest to Lucet and colleagues that the risk of spreading MRSA around a household appears to be small.

Nonetheless, they say, household contacts should apply infection control measures similar to those recommended in the hospital setting, such as handwashing and using gloves when performing procedures.

SOURCE: Archives of Internal Medicine, August 10/24, 2009.

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