Hepatitis B is an infectious hepatitis caused by the hepatitis B virus (HBV). This infection has two phases; acute phase and chronic phase.
- Acute hepatitis B refers to newly acquired infections. Affected individuals experience symptoms approximately 1 to 4 months after exposure to the virus. This is the incubation period of hepatitis B. In most people with acute hepatitis, symptoms resolve over weeks to months and they are cured of the infection. However, a small number of people develop a very severe, life-threatening form of acute hepatitis called fulminant hepatitis.
- Chronic hepatitis B is an infection with HBV that lasts longer than 6 months. Once the infection becomes chronic, it never goes away completely.
Approximately 90% to 95% of infected adults are able to fight off the virus so their infection is cured. Only about 5% to 10% of adults infected with HBV go on to develop chronic infection. Children are at much higher risk for chronic infection than adults. Up to 90% of infected young children will fail to clear the virus from their bodies and go on to develop chronic infection.
About two-thirds of people with chronic HBV infection are chronic carriers. These people do not develop symptoms, even though they harbor the virus and can transmit it to other people. The remaining one third develops “chronic active” hepatitis, a disease of the liver that can be very serious and life threatening. Continue reading