The hepatitis B titer is a blood test that checks for immunity due to previous vaccination or exposure to hepatitis B, according to The Vaccine Center and Travel Medicine Clinic. The test measures the level of immunity to determine if a person requires a booster shot to prevent infection from the disease.
The hepatitis B virus is a major cause of liver disease and is spread through blood and body fluids, says The Vaccine Center and Travel Medicine Clinic. Certain people are at higher risk of contracting the virus, and therefore should obtain titer testing to check their immunity. This includes health care workers, people with weakened immune systems and those with sexual contact with an infected person. Babies are also at risk if their mothers are infected.
Infection with the hepatitis B virus does not always lead to chronic infection, explains Mayo Clinic. Many adults recover fully from the infection within a few months, as their immune system clears the virus from the body. However, in some cases, the person's immune system cannot successfully fight off the infection, leading to chronic, possibly lifelong, illness. Over time, this can cause cirrhosis or liver cancer. While the vaccine provides immunity and prevents a person from getting hepatitis B, there is no cure for a person who is already infected.