Outbreak of cryptosporidiosis in Guadarrama (Autonomous Community of Madrid)

In spring of 1998, an acute gastroenteritis outbreak, which mainly affected preschool children, took place in Guadarrama (Community of Madrid, Spain). A descriptive and analytical (cases and controls) study of the outbreak was done. Stool samples of the cases were taken to microbiological investigation. The tap water getting system of the municipality was inspected and samples were collected to microbiological analysis. Twenty one children from 0 to 5 years-old had liquid diarrhea which lasted more than five days. A significant statistical association was found within tap water consumption and gastroenteritis [OR = 5.73 (1.18-43.30); p < 0.05]. It did not have association with other variables investigated. Cryptosporidium parvum (Cp) oocysts were detected in stool samples of eight cases. Deficiencies were observed in the tap water getting and treatment system of the municipality but no oocysts were found in the analysis of the water. The results of the epidemiological investigation support that the source of the gastroenteritis outbreak was tap water, likely contaminated with Cp. While this parasite was not detected in the analysis of the water, it is explainable for the difficulties which this technique involves. In our review similar descriptions of outbreaks have not been found in Spain, but it seems that this reports are not infrequent in neighbour countries. Therefore, Cp should be borne in mind in diagnostic and management of these situations.