Legionnaires' disease in a newly constructed long-term care facility.

OBJECTIVES

To determine whether a newly-constructed long-term care facility would become colonized with Legionella and whether Legionnaires' disease would occur in residents of this new facility.

DESIGN

Prospective environmental surveillance of the hospital's water distribution system for the presence of Legionella pneumophila during construction. Utilization of diagnostic tests for Legionnaires' disease in cases of nosocomial pneumonia.

SETTING

The Pittsburgh VA Health Care System, Aspinwall Division, a two-building 400-bed complex.

PARTICIPANTS

Six patients who acquired Legionnaires' disease while in the facility.

INTERVENTION: Installation of copper-silver ionization systems.

MEASUREMENTS: Isolation of L. pneumophila from potable water and the occurrence of Legionnaires' disease.

RESULTS

L. pneumophila serogroup 1 was recovered from the water distribution system within 1 month of operation; 74% (61/82) of distal sites were positive during construction. In the first 2 years of occupancy, six cases of legionellosis were diagnosed. Both clinical isolates of L. pneumophila were identical to environmental isolates by pulsed field gel electrophoresis (PFGE). Copper-silver ionization systems were installed to control Legionella in the water system.

CONCLUSIONS

We conclude that long-term care residents are at risk for acquiring nosocomial Legionnaires' disease in the presence of a colonized water system, even in a newly constructed building.