Hepatitis B Surface Antibody, Quantitative

The hepatitis B surface antibody (anti-HBs) is a blood test that measures the level of antibodies produced by the body in response to the hepatitis B virus. The antibodies provide immunity against future infection with the virus.

A quantitative anti-HBs test measures the specific concentration of hepatitis B surface antibodies in the blood. This test is important in determining the level of protection against hepatitis B infection. A high level of anti-HBs indicates that the person is immune to hepatitis B, either through previous vaccination or natural infection.

This test is often used to check immunity in individuals who have been vaccinated against hepatitis B or who may have been exposed to the virus. It is also used to determine the need for booster doses of the hepatitis B vaccine.

The results of the quantitative anti-HBs test are typically reported in International Units per liter (IU/L). The interpretation of the results may vary depending on the specific laboratory reference ranges.