Hepatitis A Virus

Hepatitis A Virus

Single stranded RNA picovirus with           incubation period of 3-6 weeks    

Clinical Features

 - Asymptomatic or mild, rare after childhood.
 - Rarely fulminant hepatitis (0.1%).

Ø Occurs worldwide & is endemic in places with substandard hygiene (people may have

detectable antibodies by age of 10y).

Ø Spread is by contaminated water & food   (oral route).

Ø Virus is shed in stool for 2-3 wks before & 1 wk after onset of jaundice, can also be detected in serum & saliva.

Ø Because HAV viremia is transient, blood-borne transmission occurs only rarely; therefore, donated blood is not specifically screened for this virus.

Ø Specific anti-HAV IgM antibodies at onset of symptoms (diagnostic marker in acute infection), titer declines in months.

Ø IgG persists for years, providing protective immunity against re-infection by all strains of HAV.