Hepatitis A

What is hepatitis A?
Hepatitis A infection is an acute self-limiting disease of the liver caused by the hepatitis A virus.

What are the symptoms of hepatitis A?

• Many people, particularly young children, do not develop any symptoms. In general, the severity of the disease increases with age.
• The most common symptoms are fever, loss of appetite, nausea, fatigue and abdominal pain, followed within a few days by jaundice.
• Clinical severity varies from a relatively mild illness lasting 1-2 weeks to a severely disabling illness lasting months.
• Prolonged relapsing hepatitis for up to one year occurs in 15% of cases. Chronic (long-term) infection does not occur.
• A small proportion of cases develop a severe overwhelming hepatitis. Death is estimated to occur in 0.1% to 0.3% of cases, although this increases to 1.8% in adults >50 years of age.

What is the incubation period for hepatitis A?
The incubation period (time from infection to onset of symptoms) is 15 to 50 days, the average being 28 days.

How is hepatitis A spread?
Hepatitis A virus is primarily spread from person to person via the faecal-oral route. It may also be spread through food that has been contaminated by infected food handlers or by contaminated water. The virus is shed in the faeces of infected people. They are most infectious in the week or two before onset of symptoms and may be infectious up to one week after onset.

Where is hepatitis A a problem?
Hepatitis A infection occurs worldwide, but the risk of infection varies with the levels of sanitation and personal hygiene. Ireland is considered a low incidence country.

Can hepatitis A be treated?
There is no specific treatment for hepatitis A. Therapy should be supportive and aimed at maintaining comfort and adequate nutritional balance.

How can hepatitis A infection be prevented?
Preventive measures for hepatitis A include:

• Good personal hygiene, with special emphasis on careful hand-washing after using the toilet and before preparing and eating food.
• Clean water and good sanitation, with sanitary disposal of faeces.
• Immunisation through the administration of vaccine and/or human normal immunoglobulin (HNIG) in certain situations

Is hepatitis A a notifiable disease?
Hepatitis A is a notifiable disease under the Infectious Diseases Regulations. Cases should be notified to the Medical Officer of Health.

Hepatitis A vaccination
There is a safe and effective vaccine available for hepatitis A. It is available either as a vaccine on its own, or combined with hepatitis B vaccine. Recommendations for the use of vaccine and HNIG to prevent secondary cases and outbreaks are detailed in the Immunisation Guidelines for Ireland (2008). Vaccination is recommended for those at increased risk, including:

• Travellers to high-risk areas (Africa, Asia, Central and South America, Eastern Europe and the Middle East)
• Susceptible people with chronic liver disease
• People with haemophilia and recipients of plasma-derived clotting factors
• Injecting drug users
• Men who have sex with men
• Laboratory workers who may be exposed to hepatitis A
• People in recent close contact with infected individuals.

Other high risk groups may also be considered for immunisation and are listed in the Immunisation Guidelines for Ireland (2008)

Travel advice
Hepatitis A vaccination is recommended for travellers to certain countries. Further information is available from Fit For Travel

Last reviewed: 28th August 2008