Preventing Legionnaires’ disease in long term care facilities?

Do you believe there is a benefit to residents in LTC facilities in identifying Legionella infections? What interventions can LTC facilities implement to prevent and manage these infections.


There is clearly a benefit to identifying Legionella infections in long-term care facilities. In the absence of an influenza or respiratory syncytial virus outbreak, most pneumonias in long-term care facilities are due to aspiration of the bacteria colonizing the patient’s pharynx. Indeed, many studies have identified swallowing difficulty, tube feeding, and other markers for a tendency to aspirate as major risk factors for pneumonia in this population. Prevention is problematic, since the underlying problem is inability to protect the airway.

Legionella infection, on the other hand, is acquired from the environment. If there is no Legionella in the environment, then disease cannot occur. Thus, unlike most types of pneumonia in the long-term care setting, Legionella is highly preventable. In addition, most patients in long-term care facilities are treated for infection without benefit of specific microbiologic diagnosis. In the case of pneumonia, this is particularly true, since sputum samples are notoriously hard to obtain in this population. A diagnosis of Legionnaires’ disease permits specific, pathogen directed therapy, and avoids overly broad empiric therapy (identified by many experts as a particular issue in nursing homes).

Our specific recommendation would be to perform surveillance cultures for Legionella on the facility’s water system. If L. pneumophila serogroup 1 is identified, patients with pneumonia are easily tested with Legionella urinary antigen. This would provide a basis for a rational decision on whether or not to perform eradication procedures. See article by Seenivasan JAGS 2005.