Hospitals, nursing homes hotbeds of Legionnaires' disease

Nursing homes and hospitals need to do more to protect their patients from catching Legionnaires' disease from contaminated water systems in their buildings, US health officials warned on Tuesday.

An analysis of more than 2,800 cases of the disease that occurred in 2015 found that 553 definitely or possibly occurred in a health care facility such as a nursing home or a hospital, according to the Morbidity and Mortality Weekly Report published by the Centers for Disease Control and Prevention. Of these, as many as 66 patients died from the disease.

"It's widespread, it's deadly and it's preventable," said CDC acting director Anne Schuchat.

One 2016 study showed that following hotels, long-term care facilities and hospitals are the most common types of buildings associated with Legionnaires' disease outbreaks that CDC investigated. In CDC's most recent Vital Signs report, experts gathered case data from 20 states and one large city with the goal of learning more about Legionnaires' disease infections associated with health care facilities and identifying ways to prevent new infections.

This is the first time CDC has looked at state and city level data on healthcare source for Legionnaires' disease, and found 76 per cent of the areas that were analysed had residents who definitely became infected with Legionnaires' disease during a stay at a health care facility.

Among cases with definite health care exposure, four out of five were associated with long-term care facilities, one out of five with hospitals, and some had stayed in both. Among cases with possible health care exposure, 13 per cent were associated with long-term care facilities, 49 per cent with hospitals, and 26 per cent with outpatient clinics.

Legionnaires' disease is not new, though it is seldom heard of. It is a potentially life-threatening form of pneumonia caused by Legionella bacteria, which can grow in water systems such as water storage tanks or pipes. The elderly and people who have weakened immune systems because they are sick are especially at risk.

Dr Schuchat wrote for CNN: ''Over 40 years ago, a group of American Legionnaires returning from a convention in Philadelphia were sickened with a mystery respiratory disease. Sadly, some died, and many others were hospitalized. This sudden illness prompted the Centers for Disease Control and Prevention to launch the agency's largest outbreak investigation to date, sending more than 20 disease detectives into the field to try to find the source and activating hundreds at headquarters to evaluate specimens in order to find the source of the severe pneumonia.

Their investigation ultimately identified a bacterium, Legionella, for the first time associated with the hotel's air-conditioning system that triggered severe cases of pneumonia. Four decades have passed since Legionnaires' disease was defined, yet it is increasing in incidence and now recognised that many infections in the United States can be prevented.''

The CDC says hospitals and nursing homes need to work harder to keep the bacteria from getting into places where patients might be exposed, such as showers, sinks and bathtubs, as well as medical equipment that uses water.

Schuchat says she was surprised by the number of cases associated with health care facilities. They need to be especially attentive to the problem, given the vulnerabilities of their patients, she says.