Hepatitis A Vaccine
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Hepatitis A Vaccine

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What Is Hepatitis A?

Hepatitis A is a viral infection that strikes the liver. The virus causes the liver to become inflamed, and liver function is reduced. Waste that is normally excreted by the liver builds up in the blood, and jaundice usually results.

Hepatitis A is passed from person to person through contact with feces. You can contract the virus from an infected child by changing a diaper, or by having sexual contact with an infected person. Hepatitis A can also contaminate and be contracted through food and water.

Hepatitis A virus is very common in developing countries, but it also occurs in the United States.

Symptoms of hepatitis A include:

  • Jaundice
  • Fatigue
  • Abdominal pain or soreness
  • No appetite
  • Nausea
  • Headache, chills

There is no treatment for hepatitis A, but there are lifestyle changes that can reduce symptoms when they occur. If you suffer from fatigue, get plenty of rest. Maintain a healthy, balanced diet, and avoid alcohol.

At times, people with hepatitis A may require hospitalization. Rarely, the infection can be fatal if the liver is extensively damaged.

What Is the Hepatitis A Vaccine?

The hepatitis A vaccine contains a killed or inactivated form of the hepatitis A virus. It is administered as a subcutaneous injection in the arm.

The hepatitis A vaccine should be stored in a cool environment, between 35˚F-47˚F, but it should not be frozen.

A combined vaccine that protects against both hepatitis A and B is also available.

Who Should Get Vaccinated and When?

The hepatitis A vaccine is recommended for all children aged 12 months. The two doses of the series are given 6 months apart. Children who have not been vaccinated can receive the shot at their next doctor's visit.*

The following individuals should also get vaccinated:

  • Children age 12 months or greater in high-risk areas
  • Individuals traveling to areas where hepatitis A is prevalent
  • Individuals who engage in anal sex
  • Drug users
  • Individuals with chronic liver disease
  • Individuals with blood-clotting disorders, like hemophilia
  • Children who live in areas where hepatitis A is prevalent

People who are traveling should begin their hepatitis A vaccinations at least 2-4 weeks before departure.

What Are the Risks Associated With the Hepatitis A Vaccine?

There is a risk of severe allergic reaction to the hepatitis A vaccine, with symptoms such as difficulty breathing, skin rash, rapid heartbeat, dizziness, or wheezing. Less common moderate side effects include:

  • Soreness at the site of injection
  • Headache
  • Loss of appetite
  • Fatigue

Who Should Not Get Vaccinated?

The following individuals should not get vaccinated:

  • Children under one year of age
  • Anyone who has already had hepatitis A
  • Anyone who has previously had a severe allergic reaction to the hepatitis A vaccine
  • Anyone who has previously had a severe allergic reaction to any component of the hepatitis A vaccine (including alum or 2-phenoxyethanol or neomycin)
  • Anyone who is ill at the time they want to receive the vaccination should wait until they have recovered
  • Pregnant women

What Other Ways Can Hepatitis A Be Prevented Besides Vaccination?

  • Wash your hands frequently with soap and water, especially after using the restroom or changing a diaper.
  • Immune globulin (proteins used to fight infections) given before and after viral exposure is another way of preventing and treating hepatitis A.

What Happens in the Event of an Outbreak?

If a food-borne hepatitis A outbreak occurred, the source of the contaminated food would be identified and eliminated. In any hepatitis A outbreak, the affected community should receive vaccination to prevent the spread of the virus.


National Digestive Diseases Information Clearinghouse

US National Library of Medicine


The American Academy of Family Physicians website. Available at: http://familydoctor.org/897.xml. Accessed February 6, 2007.

Hepatitis A: frequently asked questions. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/NCIDOD/diseases/hepatitis/a/faqa.htm#travel. Accessed February 1, 2008.

National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/ncidod/diseases/hepatitis/a/fact.htm. Accessed February 6, 2007.

*Updated Who Should Get Vaccinated and When section on 1/31/2008 according to the following study, as cited by DynaMed's Systematic Literature Surveillance http://www.ebscohost.com/dynamed/what.php: Centers for Disease Control and Prevention. Recommended immunization schedules for persons aged 0-18 years—United States, 2008. MMWR. 2008;57;Q1-Q4. Centers for Disease Control and Prevention, MMWR website. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5701a8.htm. Updated January 10, 2008. Accessed January 28, 2008.

Last reviewed February 2008 by David Horn, MD, FACP

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

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