Hepatitis B virus (HBV) is a hepatophilic deoxyribonucleic acid virus, which belongs to the enveloped virus. The viral markers now used in clinical practice are hepatitis B virus surface antigen (HBsAg), surface antibody (anti-HBs), e antigen (HBeAg), e antibody (anti-HBe), core antigen (HBcAg), core antibody (anti-HBc), etc. The test includes HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc, and with the development of the method, HBcAg has also been added to the scope of the test. Reference value] In normal people who have never been infected with hepatitis B and have never been vaccinated with hepatitis B, all of the above indicators are negative. [Positive Clinical Significance] 1. HBsAg positive: seen in the latent phase of acute hepatitis B, peaking at the onset. If it does not turn negative 3 months after the onset, it will easily develop into chronic hepatitis B or liver cirrhosis. HBsAg is also positive in carriers. HBsAg is the outer shell of the hepatitis B virus and does not contain DNA, so HBsAg itself is not infectious, but HBsAg can exist for years in asymptomatic carriers and chronic HBV patients, so it is often used as one of the markers of HBV infection. 2. anti-HBs: This is a protective antibody that prevents the hepatitis B virus from crossing the cell membrane and entering new liver cells. A positive anti-HBs indicates that the body has some degree of immunity to the hepatitis B virus. Anti-HBs usually begins to appear late in acute infection, some time after HBsAg turns negative, with a large peak in 6-12 months, and can last for years, but the titer gradually decreases. Positive indicates immunity to HBV and is recommended for those recovering from hepatitis B, past infections and those who have received hepatitis B vaccine or anti-HBs immunoglobulin. 3. HBeAg positive: It can be used as a marker of HBVDNA replication and high infectivity. Positivity in pregnant women can cause vertical transmission (i.e., transmission to the fetus through the placenta). Acute infection disappears after the extreme phase of the lesion, and if persistently positive predicts a tendency to chronicity. In chronic HBV infection HBeAg positivity is an important immune tolerance factor and its presence in most cases indicates that the patient is in a high infection low response phase. 4. Anti-HBe positive: indicates that most of the hepatitis B virus is cleared, less viral replication, and less infectious, but not non-infectious. Some patients are still infectious and hepatitis active, called HBeAg-negative chronic hepatitis B. Those who appear anti-HBe positive in the acute phase of hepatitis B are prone to progress to chronic hepatitis B. Chronic active hepatitis with anti-HBe positivity suggests progression to cirrhosis. 5. anti-HBc: It is mostly positive in hepatitis B virus carriers, and still about 6% of surface antigen negative people are positive, so it can be used as a sensitive indicator of hepatitis B virus infection in surface antigen negative people. (Positivity is a marker of HBV infection, regardless of whether HBV is cleared or not) Hepatitis B virus marker detection and analysis HBsAg anti-HBs HBeAg anti-HBe anti-HBe anti-HBc anti-HBc-IgM Test result analysis ＋ – ＋ – – – Early stage of acute hepatitis B virus infection with active viral replication. ＋ Acute or chronic hepatitis B acute attack with active viral replication, commonly known as “major triple positive”. + – – – – – + + Acute or chronic hepatitis B acute attack with reduced viral replication. + – – – – + + + Acute or chronic hepatitis B acute attack with reduced viral replication, commonly known as “minor triplets”. + – – – – + + – – Reduced hepatitis B viral replication, also known as “small triple yang”. – – – – + + – Surface antigen/surface antibody blank phase, probably in quiet carriage (recovery from acute infection) – – + + + + – Stage prior to the appearance of surface antibodies, with low viral replication – ＋ – ＋ ＋ – Stage of recovery from hepatitis B virus infection. – + – – – + – Stage of recovery from hepatitis B virus infection. ＋ ＋ ＋ – ＋ ＋ ＋ Reinfection with different subtypes of hepatitis B disease, i.e. viral mutation. + – – – – – Hepatitis B virus in an integrated state, i.e. early stage of infection. – + – – – – Acquired immunity after illness or after hepatitis B vaccination. – + – – – – Surface antigen mutation. + + + – + – – Surface antigen, e antigen variant.