[Point processes as a tool for analyzing possible sources of contamination]

Point pattern analysis pattern comprises a series of techniques that enables the distribution of a series of events occurring in the vicinity of a particular region of a map to be studied. In epidemiology, this problem arises when a potential source of environmental contamination, possibly leading to cases of a specific disease, is investigated.The present study provides a brief description of point pattern analysis. The approach is illustrated through determination of the environmental source and study of the areas of greatest risk of incidence of an outbreak of legionella pneumonia that occurred between the middle of September and beginning of October in the city of Alcoi in Alicante (Spain).Point pattern analysis was able to confirm the environmental source of the outbreak and identify the areas of the city at greatest risk. This provided the justification for an exhaustive inspection of the installations generating aerosols after which, to date, the epidemics ceased.