Cholera Peru epidemic

Bacteria in water are usually thought of in terms of human disease. Indeed, until quite late in the nineteenth century, disastrous outbreaks of waterborne diseases such as cholera, dysentery, and typhoid fever were common in the major cities of the world. The last outbreak of typhoid in the United Kingdom occurred in Croydon in 1937. Serious cholera epidemics still occur in some parts of the world one that began in Peru in 1991 spread to several countries in the Americas, causing 391,000 cases of illness and 4000 deaths that year. 

Petrera, M. and Montoya, M. 1992. The economic impact of the cholera epidemic, Peru, 1991. Epidemiological Bulliten, PAHO 13 9-12. 

This cruel experiment was unintentionally conducted in Peru in the 1980s. The result was a cholera epidemic affecting 300,000 people and causing 3,500 deaths. In the United States in 1994, problems in the water chlorination system of Milwaukee resulted in over a third of a million people being sickened by the protozoan, Cryptosporidium. Similarly, as discussed earlier in this book, the removal of DDT from Africa resulted in millions of deaths secondary to a resurgence of once-controlled malaria. The human trials have been done and, in retrospect, the benefit-to-risk ratio favors DDT and chlorine. Chlorine has not yet been banned. Why is there even any debate ... 

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