Hepatitis A & Its Vaccine

    Hepatitis A & Its Vaccine

    What Is It?

    Hepatitis A is a highly contagious liver infection caused by the hepatitis A virus. It can cause inflammation that affects your liver’s ability to function. Globally there are an estimated 1.4 million cases of hepatitis A across the world every year, according to the World Health Organisation (WHO).

    Hepatitis A remains a significant problem in Malaysia as it is among those countries reported to be of intermediate endemicity, along with Thailand and Sri Lanka. In East Malaysia, the hepatitis A virus has been reported to be the main cause of symptomatic clinical hepatitis. Malaysia’s love for shellfish, especially cockles, puts us at greater risk of infection because shellfish are known to be effective carriers of the hepatitis A virus.

    Infection usually occurs via the faecal-oral route, via the ingestion of contaminated food and water. Contaminated shellfish and salads are frequent sources for hepatitis A outbreaks.  Food contaminated by infected workers in food processing plants and restaurants are also a common source for infection. An infected person is usually infectious during the first week of illness and can remain infectious for 2-3 weeks before he or she exhibits symptoms.




    Signs And Symptoms

    Typical signs and symptoms of hepatitis A can last about 2 months and include:

    • Jaundice
    • Dark urine
    • Fever
    • Tiredness
    • Loss of appetite
    • Nausea
    • Abdominal discomfort

    10-15% of affected individuals will have prolonged or relapsing disease lasting up to 6 months. Individuals with chronic liver disease are at increased risk for acute liver failure. Anyone who has not been infected before or vaccinated against hepatitis A is at risk of contracting the infection.

    Hepatitis A infections often occur during early childhood. Young children do not exhibit symptoms if infected but can still pass the infection onto other family members.


    Who Is At Risk?

    People most likely to get hepatitis A are:

    • International travellers, particularly those traveling to developing countries
    • People who live with or have sex with an infected person
    • People living in areas where children are not routinely vaccinated against hepatitis A, where outbreaks are more likely
    • Day care children and employees, during outbreaks
    • Men who have sex with men
    • Users of illicit drugs



    There is no treatment for HAV other than supportive care so prevention is especially important.

    The hepatitis A vaccine offers immunity to adults and children older than age 12 months. Hepatitis A vaccination is administered in two doses, 6 months apart. It is recommended for children aged 12 months and above, and for adults who are at high risk for infection.

    Another effective method to prevent infection is maintaining proper hygiene – always wash your hands after using the bathroom, changing a diaper and before preparing or eating food. When travelling overseas, avoid drinking tap water and remember to be mindful of hygiene and sanitation as well to help prevent hepatitis A.