Causes of hepatitis A
Learn about the cause of hepatitis A, how it’s spread and where it’s found.
On this page
The cause of hepatitis A
Hepatitis A is a liver disease caused by the hepatitis A virus. It’s different from other types of hepatitis, such as hepatitis B and C.
How hepatitis A is spread
Hepatitis A is most commonly spread when someone eats food or drinks water that contains the hepatitis A virus. This is more likely when travelling outside Canada in areas of the world where hepatitis A is more common. Contaminated sources may include:
- ice
- raw or undercooked shellfish
- raw or frozen fruits and vegetables (peel them yourself to reduce risk)
Hepatitis A can also spread:
- by eating foods prepared by an infected person
- from person to person (rarely) through:
- sexual contact with an infected person
- contact with the feces of an infected person
- blood transfusions or sharing needles for drug use
- changing diapers or cleaning up stool from an infected person
Even if you do not have symptoms, you can still infect others. Infected infants and children are more likely to be without symptoms than infected adults.
You can spread the virus starting 2 weeks before you show any symptoms. You can continue to infect others until about a week after you get jaundice (yellowing of the skin and eyes).
How food and water become contaminated
Food and water become contaminated with the hepatitis A virus when they come in contact with feces from infected people. This can happen when:
- sewage is not properly disposed of and mixes with drinking water
- an infected person does not wash their hands properly after using the bathroom and then prepares food
- a caregiver for an infected person does not wash their hands properly after giving care and then prepares food
- contaminated water is used:
- on crops
- in food processing and packaging
Where hepatitis A is found
The hepatitis A virus can be found in sewage and untreated water.