[Aggregation of cases of legionella pneumonia in workers related to the ceramic industry in Castellon, Spain, 2006].

Background: Cases of legionellosis sometimes arise in the form of aggregations which are difficult to interpret. This study provides an analysis of these groupings having arisen one summer in Castellon.
Methods: Microbiological, clinical and epidemiological field methods were employed.
Results: Within a few days, there were five (5) cases of legionella pneumonia in workers related to various ceramic industries within an area where a large number of these plants are located. Two constituted a minor outbreak. By means of molecular biology techniques performed on the strains, the common origins of three of the cases were ruled out.
Conclusions: It is debated whether this episode of an outbreak having arisen within the context of a broader-ranging cluster of cases of a multi-focal origin was a chance event or whether it was the manifestation of a risk related to this industrial activity which might repeat itself.