[Epidemiologic outbreak of Legionnaire's disease in an open community: 10 years later]

The aim of this study was to describe an outbreak of pneumonia due to L. pneumophila in Llutxent (Valencia) and to know the evolution of these patients 10 years after.

The definition and identification of cases was carried out with the use of IFI techniques. An environmental and epidemiological study was performed for determining the origin and route of disease dissemination. The patients were clinically, functionally and serologically reviewed 10 years after.

From July to August 1983, 35 cases of pneumonia were reported in Llutxent (rate = 1.5%). L. pneumophila serotype 1 was serologically identified and was also found in shower heads and toilet tanks (in the context of the entry of sand into the drinking water supply). Ten years after, the patients had no respiratory symptoms with titers of antibodies versus Legionella sp. being under 1/64.

The authors emphasize the involvement of the distribution system for drinking water to the population in this first outbreak of Legionnaires disease in an open community. The health care measures taken were effective as demonstrated by no further pneumonias being recorded and after normalization of the rate of antibodies on a 10 year review.