Serology is a blood test to detect the presence of antibodies against certain organisms. Hepatitis B is an inflammation of the liver. Hepatitis B serology is the study of blood that helps in the diagnosis of the disease based on the presence of antibodies.

Hepatitis B serology tests the presence of three antibodies namely HBsAg, HBeAg, and HBcAg

HBsAg or Hepatitis B surface antigen can be detected through Hepatitis B serology. The presence of this antigen indicates that the person is infectious. This is the first detectable agent and is present as early as incubation period.

The presence Hepatitis B surface antibody or anti-HBs in the Hepatitis B serology indicates recovery and immunity from HBV infection. Anti- HB s also develops in a person vaccinated against Hepatitis B. it can be measured quantitatively or qualitatively. It is reported as positive when measure qualitatively and in mill international units when expressed quantitatively. 

The detection of anti HBc or Total hepatitis B core Antibody indicates the previous ir ongoing infection with Hepatitis B virus or HBV in an undefined time frame. 

IgM anti-HBc appears in the hepatitis B serology during acute or recent HBV infection and is present for about 6 months.

If HBeAg or Hepatitis B Envelope antigen is detected in the serology then it shows a highly infectious state and chronic infection.

Anti – HBe is an antigen produced by the body temporarily during acute infection or viral replication. The presence of this antigen indicates lowering levels of HBV.  

The HBcAg positivity in Hepatitis B serology indicates active virus replication and greater infection.

The Hepatitis serology will show positivity in an infected person in an average of 4 weeks [range of 1 to 9 weeks] after exposure to virus. If the infection is not chronic then the patient will show negativity in 7 weeks time, if it stays positive even after 15 weeks then the infection is positive.

Hepatitis B serology is essential to start treatment for Hepatitis B. a wrong diagnosis and wrong treatment may be dangerous. So to diagnose correctly serology is a must. Laboratories should have trained professionals to do hepatitis B serology. The serology result gives the following possibilities like Window phase of recent infection or low-level carrier state or resolved infection or infection with a mutant HBV or non specific reactivity in the anti-HBV assay. The carrier should be careful not to spread the virus. The people in the patient's home should follow good hygiene.