Hepatitis B Surface Antigen – HBsAg
When a person is exposed to Hepatitis B viral infection, the HBsAg will appear after about three weeks. This antigen will remain in the blood for about 4 to 5 months where it will disappear (return to negative) after recovery takes place. In certain cases HBsAg will persist for very long periods (6 months to years) before it disappears. People in this group are known as suffering from chronic Hepatitis B if the liver enzymes continue to remain high. However, there are cases where there is no recovery at all even though the liver enzymes return to normal. Such groups known as carriers of hepatitis B and the HbsAg will always be positive. Both groups are known to have a higher risk of contracting liver cancer than normal people.
Hepatitis B Surface Antibody – HBsAb
When HBsAb is positive, it indicates that a person has fully recovered from exposure to a Hepatitis B viral infection. A positive result is also due to successful immunisation against the virus. Even after immunisation the level of HBsAb will drop over a period of time and if the level falls below 10mlU/ml, a booster dose is highly recommended to ensure protection against the virus.
Hepatitis A IgG Antibody – HAV IgG Ab
A positive test indicates either a recent or past infection. The test does not differentiate between the two. The cause of Hepatitis A infection is due to consumption of food or drinks contaminated with faecal matter from people infected with the virus. Generally Hepatitis A infection is less serious than Hepatitis B, and almost all will recover from the infection. Those who recover will have positive HAV IgG Ab and will be immune against the virus.