Causative Agent

There are atleast six viruses which can cause viral hepatitis. These viruses are hepatitis A,B,C,D,E and G. Commonest water borne infection due to hepatitis `A` & `E`
· HAV is enterovirus (Type 72) of Picornaviridae family.
· It multiplies only in Hepatocytes.
· Viruses are shed during & after incubation period through faeces.
· Virus is resistant to heat and chemical , survive more than 10 weeks in water & not affected by usual chlorination.
· Formalin is stated to be an effective disinfectant
· Virus inactivated by ultraviolet rays boiling ( 5 minutes) or autoclaving.
· Can survive in human being only.