ToxigenicVibrio choleraeO1 in Food and Water

Abstract

Large numbers of Vibrio cholerae are discharged in the feces of infected individuals. Inadequate sewage treatment allows water systems to become contaminated. When water becomes contaminated with toxigenic strains of V. cholerae O1 and is then used by other individuals for drinking or in food preparation, the result is often widespread disease. Cholera was one of the first epidemic diseases to be controlled by public health measures in the 19th century. In the large epidemics that have occurred during the last century, contaminated water has undoubtedly been the major vehicle of transmission, with food playing a lesser but significant role in the spread of the disease. The transmission of cholera by ingestion of contaminated food has been documented in numerous instances discussed in this chapter. Methods of enhancing the isolation of V. cholerae 01 have been developed and optimized, primarily by taking advantage of the organism's rapid generation time under certain conditions and its tolerance to alkali. V. cholerae Ol is relatively easy to isolate from water samples if the contamination is recent. Filtration techniques for examining known quantities of water and estimating the amount of contamination have been developed. Since food and water are intimately involved in transmission, people must be taught hygienic practices that limit fecal-oral transmission. Disinfection of water supplies would also prevent a great many cases, and disinfection of the home water supply may be economically feasible.