Investigation of the outbreak of cholera in Alleppey & Palghat districts, south India.

In May 1996, a massive outbreak of cholera occurred in Alleppey district of Kerala which spread to Palghat district by July 1996. Of the 575 patients hospitalized at the Alleppey Medical College hospital between May 1 and August 2, 1996, 30 deaths occurred with a case fatality rate of 5.2 per cent while of the 638 diarrhoea patients admitted at Agali PHC of Attapadi area in Palghat district, 30 (4.7%) deaths were recorded. Clinically, the patients had profuse watery diarrhoea with vomiting. The epidemic of cholera in Alleppey and Palghat districts was caused by V. cholerae O1 of the EITor biotype, Ogawa serotype which possessed both the ctxA and tcpA genes when examined by multiplex PCR. Gross contamination of water sources was incriminated as the cause of the epidemic.