Hepatitis A virus

Hepatitis A virus (RNA virus)

Hepatitis A infect liver cell and cause inflammation of liver.

Hepatitis A virus enters the body by oral route.

It most commonly causes acute hepatitis in children.

It is non- enveloped RNA virus.

It is hepatitis A vaccine preventable disease.

Structure

Hepatitis is 27 nm non enveloped single stranded RNA virus.

Source and Mode of Infection

It is by feco-oral route.

Infection hepatitis is acquired by; ingestion of contaminated food, contaminated water or milk.

Pathogenesis

Virus multiplies in intestinal and reaches liver through blood causing inflammation and swelling.

Incubation period is 2-6 weeks.

Symptoms;

Fever

Malaise

Anorexia

Nausea

Vomiting

Liver tenderness

Abdominal discomfort

Prejaundice stage

Laboratory Diagnosis

Specimen collection; blood sample

Detection of antibodies by ELISA

Used for detection of IgM and IgG.

Prophylaxis

Virus is killed by boiling for one minute or by adding chlorine in water.

Prophylaxis is improved sanitary practices and prevention of fecal contamination of food and water.

Immunization

Hepatitis A can be prevented by hepatitis A vaccine, administered intermuscular (IM).

Safe and effective vaccine against Hepatitis A virus grown in human diploid cell culture is available, it is safe and effective.

Naturally infection with hepatitis A virused leads to life long immunity.