Transmission of cholera is through ?
Man is the only reservoir. The immediate source of infection are the stools and vomits of cases and carrier. Infection is acquired through fecally contaminated water or food. Chlorination of water is effective against V cholerae. There are following tyes of carrier in cholera. i) Incubatory : Shed vibrios only in the brief incubation period of 1-5 days. ii) Convalescent : Shed vibrios for 2-3 weeks. iii) Healthy or contact carrier : Has had subclinical infection and shed vibrios for less than 10 days. iv) Chronic carriers : Can shed vibrios for months or years and may have persistent infection in gall bladder.
Fecally contaminated food
Fecally contaminated water
Contaminated food by vomits of a case
All of the above