PRIME takes you through the types of viral hepatitis.
Types of viral hepatitis
The most common types of hepatitis are hepatitis A, B and C and these are caused by three different hepatitis viruses.
Hepatitis A is caused by the hepatitis A virus and is transmitted through food or water that has been contaminated by the faeces of an infected person. If you often consume raw shellfish, do take note that one way hepatitis A can spread is when a person consumes seafood that have been contaminated by sewage in the water.
Hepatitis A is the mildest form of the infection as it causes acute hepatitis, which means that the body will be able to clear the infection within a short period of time, although some infections may cause further complications. Most symptoms develop 15 to 50 days after exposure to the virus and can last from a few weeks to several months.
Hepatitis B, derived from an infection with the hepatitis B virus, is the most common strain in Singapore and can lead to liver cancer. Hepatitis B is transmitted when a person comes into contact with infected blood or body fluids. For example, hepatitis B infections can be acquired through blood transfusion from an infected donor, through acupuncture, tattooing, ear piercing, manicures and even dental treatment if non-sterile instruments are used. Mothers who are hepatitis B carriers can also pass on the virus to their child at birth. Individuals who have unprotected sex are also at a higher risk of hepatitis B infection.
When symptoms occur, they can show up 2 to 5 months after infection although those who have been infected by the hepatitis B virus may not show any symptoms of the disease until liver damage has already progressed to a late stage.
More than 90% of hepatitis B cases are transmitted from mother to child during birth. Most adults who are infected by the virus will be able to fight of the disease but the majority of children who are infected at childbirth will carry the virus for life because they are not able to fight off the infection.
Hepatitis C, caused by the hepatitis C virus is mostly transmitted through contact with the blood or body fluids of an infected person and can lead to liver cirrhosis. Tattooing and sharing of needles among drug abusers are routes through which the virus can be transmitted. Currently, there is no vaccination for hepatitis C.
Like hepatitis B, most people do not show any signs or symptoms until many years later, when liver damage has already occurred. Where symptoms do appear, they can start to show up 1 to 3 months after infection.
Other types of hepatitis
There are two other less common types of the hepatitis virus. Hepatitis D usually occurs in people already infected with the hepatitis B virus and this ‘double infection’ can lead to a more serious outcome. Hepatitis E is spread through contaminated food and water although it usually does not lead to long-term illness or serious liver damage.