Clinical and Epidemiologic Features of a Massive Waterborne Outbreak of Cryptosporidiosis in Persons With HIV Infection

Abstract

During March and April 1993, a massive outbreak of Cryptosporidium infection resulted from contamination of the public water supply in Milwaukee, Wisconsin. The health impact of this outbreak in HIV-infected persons was unknown but was perceived as severe. We surveyed HIV-infected persons who resided in the greater Milwaukee area to examine the acute health impact of cryptosporidiosis on this population. Data from a random-digit dialing survey in the general population residing in the same area were used for comparison. The attack rate of watery diarrhea suggestive of cryptosporidiosis was lower in HIV-infected persons (32%) than in the general population (51%). There was no significant difference in attack rate in HIV-infected persons based on CD4+ T-lymphocyte count. In persons with watery diarrhea, HIV-infected persons were more likely to experience cough (42%), fever (52%), and dehydration(55%). In HIV-infected persons with watery diarrhea, persons with CD4+ T-lymphocyte counts Cryptosporidium