What is Hepatitis C?

Hepatitis C is a virus

The hepatitis C virus is one of several viruses that can cause inflammation of the liver. Currently there are five types of viral hepatitis: A, B, C, D and E.  Hepatitis C can damage the liver. The amount of damage may be slight or serious.

Hepatitis C infection involves an initial acute phase of infection that may not be noticeable, because in most cases people do not feel sick. This phase can last up to six months, levels of the virus in the blood rise dramatically until the body’s immune system starts to produce antibodies. Antibodies are made in response to the presence of the hepatitis C virus.

Chronic hepatitis C

On average, around 25% of people who contract hepatitis C will clear the virus naturally within the first 12 months. For the remaining 75% of people the virus is not eliminated. For these people the virus will probably remain in their body for the rest of their lives. This is called chronic (long term) hepatitis C.

Of 100 people with chronic hepatitis C who have remained untreated after 20 years, 45 people may not develop any liver damage;31 may develop mild to moderate liver damage;7 may develop cirrhosis of the liver and 1 may develop liver failure. After 40 years, 45 people may not develop any liver damage; 31 may develop mild to moderate liver damage; 20 may develop cirrhosis of the liver and 4 may develop liver failure.

Immunity

Unlike antibodies to other diseases, such as hepatitis A, hepatitis C antibodies do not provide any immunity to hepatitis C. Even in those people who have been infected with hepatitis C once and cleared the virus, re-infection can still occur.

Genotypes

There are several different strains of the hepatitis C virus called ‘genotypes.’ These strains are slightly different in their genetic make-up, but similar enough to still be labelled hepatitis C. It is currently believed that there are at least 6 different genotypes of hepatitis C here in Australia, which are numbered 1, 2, 3, and so on. There are also subgroups within each genotype, which are further differentiated 1a, 1b, etc. The most common genotypes found in Australia are 1 and 3.

Studies have shown that it is possible to be infected with multiple hepatitis C genotypes. To prevent re-infection with a different genotype, it is important to practise the same blood awareness precautions as for preventing an initial infection. (Link to prevention page)