|
Causative
Agent
Causative orgasism is Vibrio Cholera
There are more than 60 serogroups of vibrio cholerae , but only sero group
01 and 0139 cause cholera.
V. Cholerae 01 occurs as two biotypes-classical and EL Tor. Each
biotype also further divided each into three serological types
Inaba, Ogawa and Hikojima.
Almost all the recent cholera have been caused by the EL Tor biotype.
In Maharashtra 01 and 0139 sero groups causing cholera biotype
is found in sporadic form.
The vibrio is destroyed in an acidity of pH 5 or lower. Conditions
that reduce gastric acidity may influence individual susceptibility
.
V. Cholerae are killed within 30 minutes by heating at 56 degree.Celsius
or within a few seconds by boiling. They remain in ice for 4 to 6
weeks or longer. They
are easily destroyed by disinfectants such as cresol. Bleaching
powder is another good disinfectant which kills vibros instantly
at six miiligram
per litre.
Human being is the only known reservoir of cholera infection.
The immediate source of infection are stools and vomit of cases
and carriers.
|