Vaccination Program

Vaccine Information

Hepatitis A

Signs & Symptoms

Adults will have more noticeable signs and symptoms than children. Common signs and symptoms include:

  • jaundice
  • fatigue
  • abdominal pain
  • fever
  • loss of appetite
  • nausea
  • diarrhea

Cause

Hepatitis A virus (HAV)

Long-Term Effects

  • There is no chronic (long-term) infection.
  • Once you have had hepatitis A, you cannot get it again.
  • About 15% of people infected with HAV will have prolonged or relapsing symptoms over a 6-9 month period.

Transmission

Hepatitis A is transmitted faeco-orally - the virus is transmitted from an infected person's stool to the water or food eaten by another person. The virus can survive in water for more than a year and also in food for a few days. It can be transmitted by:

  • eating contaminated food without proper cooking especially shellfish like oysters, clams, cockles and mussels.
  • drinking contaminated water.
  • close personal contact with infected person
  • HAV is found in the stool (faeces) of persons with hepatitis A.

Persons At Risk Of Infection

  • Household contacts of infected persons
  • Persons traveling to countries where hepatitis A is common
  • Sexual contacts of infected persons
  • Men who have sex with men
  • Injecting and non-injecting drug users

Prevention

  • Hepatitis A vaccine is the BEST protection.
  • Short-term protection against hepatitis A is available from immunoglobulin. It can be given before and within 2 weeks after coming in contact with HAV.
  • Always wash your hands with soap and water after using the bathroom, changing a diaper, and before preparing and eating food.
  • Avoid eating uncooked seafood in places where hepatitis A is common.

Vaccine Recommendations

The vaccine is recommended for the following persons from 12 months of age and older:

  • Travelers to areas with increased rates of hepatitis A
  • Persons with chronic liver disease, including hepatitis B carriers
  • Men who have sex with men
  • Injecting and non-injecting drug users
  • Persons with clotting-factor disorders (e.g. hemophilia)

Trends & statistics

  • Hepatitis A tends to occur in epidemics both nationwide and in smaller communities.
  • In Hong Kong the most recent outbreak in 1992 resulted in more than 3000 cases and 4 deaths.
  • The annual number of reported cases of hepatitis A in Hong Kong fell from over 1000 in 1988 to only a few hundred in recent years.
  • More than half of the people in Hong Kong below the age of 30 have never been infected.
  • In USA during epidemic years the number of reported cases reached 35,000.
  • In the late 1990s the hepatitis A vaccine was more widely used and the number of cases reached historic lows.

More About Hepatitis A

Hepatitis A FAQ

Hepatitis A Vaccine

The Hepatitis A vaccine can be given to adults as well as children. It is recommend for people living in Hong Kong, especially anyone who is required to travel frequently to mainland China or other South East Asian countries for work or leisure.

A single injection of the hepatitis A vaccine can induce immunity that lasts for 3 years. However most people choose to have a second injection within 6 to 12 months, so that the protection is extend to over 10 years. For those who do not have immunity to hepatitis B they may have Twinrix; a combined hepatitis A and B vaccine, which reduce the number of injections from 5 to 3.