A Waterborne Epidemic of Salmonellosis in Riverside, California, 1965 Epidemiologic Aspects a Collaborative Report1

Riverside County Health Dept; California State Dept. Public Health (Berkeley); Center for Disease Control (Epidemiology Program, Atlanta, Ga. 30333); National Center for Urban and Industrial Health (Cincinnati, Ohio). A waterbome epidemic of salmonellosis in Riverside, California, 1965. Epidemiologic aspects. Amer J Epidem 93: 33–48, 1971.—The clinical and epidemiologic aspects of an epidemic of acute gastroenteritis occurring in Riverside, California, 1965, are described. A total of more than 16, 000 cases occurred; at least 70 patients were hospitalized and three died. The causative agent was Salmonella typhi-murium phage type 2, which contaminated the municipal water supply. Water was obtained from deep wells and the exact source of contamination was not determined. However, the outbreak was brought under control by recognition of contamination and chlorination of the water supply.