Vaccines for Hepatitis A and B
Our immune system battles foreign invaders every day, such as when we get a cold virus. When this happens, we develop immunity to that specific virus. This means that our body will fight off the virus if it is ever exposed to it again.
The same protection happens with vaccines. However, the benefit of a vaccination is that you don't have to go through being sick to enable your body to fight off disease.
Gregory Poland, MD, director of the Mayo Clinic's Vaccine Research Group, explains that hepatitis vaccinations contain a small amount of the inactive virus. When you get a dose of the vaccine, he says, your immune cells respond by developing immunity against the virus. This immunity lasts over a long period of time.
"So if I get these two doses of hepatitis A vaccine, and then I get exposed 30 years from now, my body will remember that immunity to the vaccine and rapidly start producing antibodies again," says Poland.
Due to the way hepatitis vaccinations are developed, it is impossible to contract the virus from the vaccine itself, according to Poland.
The hepatitis A vaccine is usually given in two shots and the hepatitis B vaccine is administered as a series of three shots. The most common side effects are redness, pain, and tenderness where the shots are given.
To get long-term protection from these viruses, it's important to receive all the shots as scheduled. However, if you received one shot and never went back for the others, it's not too late to catch up.
"No matter how long the lapse is between doses, you never have to start the series again," says Poland. "You just take off where you left off. So even if someone got their first dose five years ago, we start with the second dose."
Who Should Get Hepatitis Vaccinations?
Since the vaccines were first developed, the hepatitis A and B vaccines have become part of the regular childhood immunization schedule. They are not considered a routine adult immunization.
"When we're talking about adults, I would say yes, get the vaccine if they fit into one of these risk factors" says Poland. "If they don't fit into the risk factors, their risk is so low that there's no compelling reason to do it."
People at risk for hepatitis A include:
- Anyone traveling to or working in areas where hepatitis A is more widespread.
- People whose work puts them in potential contact with hepatitis A, such as those who work with the hepatitis A virus in research labs
- People who are treated with clotting-factor concentrates
- People who have chronic liver disease
- People who use recreational (street) drugs, injected or not
- Men who have sex with men