What is hepatitis B?

Hepatitis B is a highly contagious liver infection caused by the hepatitis B virus (HBV). The infection can range in severity from being mild or acute, lasting just a few weeks to a serious, chronic health condition.

The best way to prevent this infection is to get the hepatitis B vaccine. Here’s what you need to know:

The hepatitis B vaccine — sometimes known by the trade name Recombivax HB — is used to prevent this infection. The vaccine is provided in three doses.

The first dose can be taken on a date you choose. The second dose must be taken one month later. The third and final dose must be taken six months after the first dose.

Adolescents 11 to 15 years old may follow a two-dose regimen.

Who should get the HBV vaccine?

The Centers for Disease Control and Prevention (CDC) recommends that children should get their first hepatitis B vaccine at birth and complete the doses by 6 to 18 months of age. However, the HBV vaccine is still recommended for all children if they haven’t already gotten it, from infanthood up to 19 years old. Most U.S. states require a hepatitis B vaccine for school admittance, however.

It’s also recommended for adults at an increased risk of catching the HBV infection, or anyone who fears they have or will be exposed to it in the near future.

The HBV vaccine is even safe to administer to pregnant women.

Who should not get the hepatitis B vaccine?

Generally seen as a safe vaccine, there are some circumstances in which doctors advise against receiving the HBV vaccine. You shouldn’t have the hepatitis B vaccine if:

  • you’ve had a serious allergic reaction to a previous dose of the hepatitis B vaccine
  • you have a history of hypersensitivity to yeast or to any other vaccine components
  • you’re experiencing a moderate or severe acute illness

If you’re currently experiencing an illness, you should postpone receiving the vaccine until your condition has improved.

How effective is the vaccine?

Research from 2016 showed that the vaccine results in long-term defense against the virus. Studies indicated protection for at least 30 years among healthy vaccinated individuals who started the hepatitis B vaccination before they were six months old.

As with any medication, the hepatitis B vaccine may cause some side effects. Most people don’t experience any unwanted effects. The most common symptom is a sore arm from the injection site.

When receiving the vaccination, you’ll likely receive information or a pamphlet regarding the side effects that you might expect, and others that warrant medical attention.

Mild side effects usually last only a day or two. Mild side effects of the vaccine include:

Experiencing other side effects is rare. If you do experience these rare, more severe side effects, you should call your doctor. They include:

Hepatitis B vaccine side effects vary from one person to the next. If you have symptoms of an allergic reaction, immediately return to the doctor. Any side effects that you experience may need medical attention, so call your doctor to discuss any unusual physical changes following receiving the vaccine.

According to the CDC, the potential risks associated with the hepatitis B virus are much greater than the risks the vaccine poses.

Since the vaccine became available in 1982, more than 100 million people have received the HBV vaccine in the United States. No life-threatening side effects have been reported.

The hepatitis B vaccine provides greater than 90 percent protection to infants, children, and adults immunized with all three doses before being exposed to the virus.

If your doctor recommends you receive the HBV vaccine, they feel that any risks with the vaccine are far outweighed by the risks of contracting hepatitis B. Although some people experience serious side effects, it’s most likely that you’ll have few — if any — side effects at all.