Canadian researchers looked at 1,269 elderly residents of 22 long-term care facilities in Toronto, Ontario, and Montreal and Riviere-du-Loup, Quebec between September 2006 and May 2008.

The investigators noted that they focused on non-summer months because that's when higher rates of respiratory and gastrointestinal infections occur.

During the study period, 424 of the seniors visited an emergency department for a variety of conditions other than acute respiratory and gastrointestinal symptoms, and 845 did not go to an emergency department.

The seniors who went to an emergency department had a higher rate of chronic illnesses and tended to be less independent than those who did not go to an emergency department.

The researchers found that seniors who visited an emergency department were about three times more likely to develop an acute respiratory or gastrointestinal infection in the week following the visit, but only if there was no outbreak in the resident's facility.

The incidence of infection was 8.3 per 1,000 resident-days among those who visited an emergency department, compared with 3.4 per 1,000 resident-days among those who didn't go to an emergency department, according to the study published in the Jan. 23 issue of CMAJ (Canadian Medical Association Journal).

"Once systemic reasons for the transmission of infection in emergency departments are understood, interventions to reduce the risk should be studied," Dr. Caroline Quach of Montreal Children's Hospital, McGill University Health Center, and colleagues, wrote in a journal news release.

"In the meantime, considerations should be given to the implementation of additional precautions for residents for five to seven days after their return from the emergency department," the study authors added.

More information

The AGS Foundation for Health in Aging has more about infections in older adults.

SOURCE: CMAJ: Canadian Medical Association Journal, news release, Jan. 23, 2012

-- Robert Preidt