What is haepatitis vaccine?

Answer 1

The haepatitis (spelled hepatitis in the US) vaccines are used to prevent infections of viral hepatitis, which is an infection of the liver. There are at least five forms of viral hepatitis in humans. They are hepatitis A, B, C, D and E. There are vaccines available that are proven safe and effective for prevention of hepatitis A and hepatitis B. However there are no vaccines available yet for hepatitis C, D or E.

Vaccines for viral diseases introduce either a dead/inactive form of the virus that causes the disease or a live/active, but severely weakened, form of the viruses into the body. It will either be injected or provided in an oral solution to drink or a mist to use as an intranasal spray, depending on the vaccine. The body's immune system then is triggered into action and produces the antibodies needed to inactivate the virus any time later that you might be exposed to the same type of virus as was in the vaccine.

There are other types of hepatitis, including hepatitis caused by other types of infectious agents and by toxic damage by chemicals or other toxins that cause the liver to get inflamed and unable to function properly. For these there are no vaccines but medical treatment can reverse the effects if begun early in otherwise healthy individuals.

(See the related questions below for more information on how vaccines work.)