Vaccine Education Center

A Look at Each Vaccine: Hepatitis A Vaccine

The hepatitis A vaccine is given to people who are traveling to parts of the world where hepatitis A virus infections are common. The hepatitis A vaccine is also recommended for all children living in the United States.

The hepatitis A vaccine is given as a series of two shots — the second administered six to 12 months after the first. Children receiving the first shot should be at least 1 year old.

The threat of hepatitis A virus

Although the threat of hepatitis A virus infection is very common in developing countries, the United States is not, by any means, hepatitis A virus-free. Each year, about 8,500 people in the United States, many of whom are children, contract hepatitis A virus. And every year about 50 people die from hepatitis A virus infection. As a result, the Centers for Disease Control and Prevention (CDC) recommends that all children between 12 and 23 months of age get the hepatitis A vaccine.

What is hepatitis A virus?

Hepatitis A is a virus that causes hepatitis (inflammation of the liver). Symptoms include fever, jaundice (a yellowing of the skin), nausea and vomiting. Young children are much less likely to develop symptoms when they are infected with hepatitis A virus than adults.

Are infections caused by hepatitis A virus similar to those caused by hepatitis B virus?

Although hepatitis A virus sounds like it would be similar to hepatitis B virus, the viral infections are really quite different. Hepatitis B virus can cause long-term problems, such as cirrhosis (chronic liver damage) and liver cancer. On the other hand, hepatitis A virus doesn't cause long-term problems. Also, hepatitis B virus kills about 750 people every year, whereas hepatitis A virus kills about 50 people every year. Finally, hepatitis B virus is transmitted by coming in contact with someone who is infected, but hepatitis A virus is typically transmitted in contaminated food or water.

How do you catch hepatitis A virus?

People infected with hepatitis A virus excrete the virus in their stools. You can catch the virus in a number of ways:

Unfortunately, people infected with hepatitis A can transmit the virus to others up to two weeks before they have symptoms, so they may be infecting others without even knowing they have hepatitis A themselves.

How can you avoid catching hepatitis A virus when traveling?

Anyone traveling to countries where hepatitis A virus infections are common should avoid the following:

To learn more about where hepatitis A exposure is most likely for travelers, consult the Centers for Disease Control and Prevention map. Additional travel information is available in the CDC travel publication, Yellow Book.

How is the hepatitis A vaccine made?

The hepatitis A vaccine is made by taking whole hepatitis A virus and killing it with the chemical formaldehyde. Because the virus is inactivated, it cannot possibly cause hepatitis (see How Are Vaccines Made?).

Does the hepatitis A vaccine have side effects?

The hepatitis A vaccine can cause pain, redness and tenderness where the shot was given. The vaccine can also cause headache in about 5 of every 100 recipients. The hepatitis A vaccine has been given to millions of people without serious side effects.

Who should get the hepatitis A vaccine?

The hepatitis A vaccine should be given to the following groups of people:

How long should I wait after getting the hepatitis A vaccine before I travel?

The hepatitis A vaccine is most effective if given at least four weeks before traveling, but the vaccine is still somewhat effective if given at least two weeks before traveling. If you are going to travel within two weeks of receiving the vaccine, it is probably better to get a shot of something called "immune serum globulin." This is a preparation of antibodies that also contains antibodies directed against hepatitis A virus. You don't develop long-lived protection by receiving "immune serum globulin," but at least it will get you through your trip. Protection afforded by immune serum globulin lasts several months.

Do the benefits of the hepatitis A vaccine outweigh the risks?

Hepatitis A virus infections are very common throughout the world. So common, in fact, that it is really easier to list the countries where you are unlikely to catch the infection than countries where you are likely to catch the infection. Also, the United States still has about 8,500 cases of hepatitis A virus every year. Although hepatitis A virus infections do not cause long-term liver damage, about 50 people die every year from severe, overwhelming infections caused by the hepatitis A virus. Because the vaccine does not have serious side effects, the benefits of the hepatitis A vaccine clearly outweigh its risks.

Who?
Infants, travelers, contacts of international adoptees and anyone who wants to avoid infection with hepatitis A
Disease Risks Vaccine Risks
  • Inflammation of the liver
  • Fever
  • Vomiting
  • Jaundice
  • Nausea
  • Pain, redness, and tenderness at the injection site
  • Headache (5 of 100)

Reference

Plotkin SA, Orenstein W, and Offit PA. Hepatitis A Vaccines in Vaccines, 6th Edition. 2012, 183-204.

Reviewed by: Paul A. Offit, MD
Date: April 2013

Materials in this section are updated as new information becomes available. The Vaccine Education Center staff regularly reviews materials for accuracy.

You should not consider the information in this site to be specific, professional medical advice for your personal health or for your family's personal health. You should not use it to replace any relationship with a physician or other qualified healthcare professional. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult your physician or, in serious cases, seek immediate assistance from emergency personnel.

 

  • Print
  • Share

Contact Us

We would like to hear from you. Please use our online form to contact us with questions or comments.

Hepatitis A Vaccine Q&A

"Hepatitis A: What you should know" Q&A sheet:

English»
Spanish»