Hepatitis A Fact Sheet

Last Reviewed: January 2023

What is hepatitis?

"Hepatitis" means inflammation of the liver. The liver is a vital organ that processes nutrients, filters the blood, and fights infections. When the liver is inflamed or damaged, its function can be affected.

In the United States, the most common types of viral hepatitis are Hepatitis A, Hepatitis B, and Hepatitis C. Heavy alcohol use, toxins, some medications, and certain medical conditions can also cause hepatitis.

What is Hepatitis A?

Hepatitis A is a highly contagious liver disease that results from infection with the hepatitis A virus. It can range in severity from a mild illness lasting a few weeks to a severe illness lasting several months. Sometimes hepatitis A can cause liver failure and death, although this is rare and occurs more commonly in people older than 50 and people who have other liver diseases.

Who gets hepatitis A?

Although anyone can get hepatitis A, certain groups of people are at higher risk, such as those who:

  • Live with or have direct contact someone who has hepatitis A.
  • Travel to or live in countries where hepatitis A is common.
  • Are family members or caregivers of a recent adoptee from countries where hepatitis A is common.
  • Are men who have sexual contact with other men.
  • Engage in sexual contact with someone infected with hepatitis A.
  • Use recreational (illegal) drugs, both injection and non-injection drugs.
  • Are experiencing unstable housing or homelessness.

How is hepatitis A spread?

Hepatitis A usually spreads when a person unknowingly ingests virus from objects, food, or drinks contaminated by small, undetected amounts of virus in the feces (stool) from an infected person. Even consuming microscopic (tiny) amounts of feces can spread hepatitis A virus.

Hepatitis A contaminated food or water occurs most often in countries where hepatitis A is common, especially in developing countries. The food and drinks most likely to be contaminated are fruits, vegetables, shellfish, ice, and water. Food can be contaminated whenever it is improperly handled, including when it is grown, harvested, and processed. Food which is not cooked thoroughly may pass on the virus, or food can be contaminated after it is cooked.

In recent years, in the United States, multiple large hepatitis A outbreaks have occurred as a result of person-to-person contact, especially among people who use drugs, people experiencing homelessness, and men who have sex with men.

Hepatitis A can also be spread when:

  • an infected person does not wash his or her hands properly with soap and water after going to the bathroom and then touches objects or food;
  • a caregiver does not properly wash his or her hands with soap and water after changing diapers or cleaning up the stool of an infected person; or
  • someone engages in certain sexual activities, such as, but not limited to, oral-anal contact with an infected person.

What are the symptoms of hepatitis A and when do they appear?

Not everyone infected with the virus has symptoms. If symptoms develop, they usually appear two (2) to six (6) weeks after exposure to the virus and can include: fever, fatigue, loss of appetite, nausea (a feeling of sickness in the stomach), vomiting, stomach pain, grey colored feces (stool), dark urine, joint pain, or jaundice (yellowing of skin and eyes). Symptoms are more likely to occur in adults than in children. They usually last less than two (2) months, although some people can be ill for as long as six (6) months. Most people who get hepatitis A recover completely and do not have lasting liver damage.

How is hepatitis A diagnosed and treated?

A doctor can determine if a person has hepatitis A by discussing the individual’s symptoms and taking a blood sample. To treat hepatitis A, doctors usually recommend rest, adequate nutrition, fluids, and medical monitoring. Some people will need to be hospitalized. It can take a few months before people begin to feel better. Hepatitis A is caused by a virus. Antibiotics are not prescribed to treat viral infections.

Does past infection with hepatitis A make a person immune?

Past infection is thought to give lifelong protection against the disease. However, vaccination is the best way to prevent infection. Vaccination of high-risk groups and other public health measures have significantly reduced the overall number of hepatitis A cases and fulminant HAV infections. Single-antigen hepatitis A vaccine was licensed for use in the United States in 1995 (Havrix) and 1996 (Vaqta). In 2001, a combination hepatitis A-hepatitis B vaccine (Twinrix) was licensed.

How can hepatitis A be prevented?

The best way to prevent hepatitis A is by getting vaccinated. Experts recommend the vaccine for all children, some international travelers, people with certain risk factors and medical conditions, and anyone who wants to be vaccinated. The hepatitis A vaccine is safe and effective and given as two (2) shots, six (6) months apart. Both shots are needed for long-term protection.

Frequent handwashing with soap and water - particularly after using the bathroom, changing a diaper, or before preparing or eating food - also helps prevent the spread of hepatitis A. Additionally, food handlers may not work while sick with hepatitis A.

In certain instances, PEP or post exposure prophylaxis (a treatment provided to try to prevent or treat a disease after someone is exposed to it), may be recommended. A health care provider can decide whether a person needs PEP after exposure to hepatitis A.

Who should get vaccinated against hepatitis A?

Vaccination is recommended for certain groups, including:

  • All children at age one (1) year.
  • Users of recreational drugs, whether injected or not.
  • People experiencing unstable housing or homelessness.
  • Men who have sex with men.
  • People who are currently or were recently incarcerated.
  • People with chronic or long-term liver disease, including Hepatitis B or Hepatitis C.
  • Travelers to countries where hepatitis A is common.
  • Family and caregivers of adoptees from countries where hepatitis A is common.
  • HIV infection.
  • People who work with Hepatitis A in research laboratory or with nonhuman primates with hepatitis A infection.
  • Pregnancy if person is at risk for infection or severe outcome from infection during pregnancy.
  • People who live or work in setting with an increased risk of exposure including health care settings targeting services to injection or noninjection drug users or group homes and nonresidential day care services for developmentally disabled persons.

Hepatitis A Vaccination Schedule

  • All children ages 12 through 23 months and all children and adolescents ages 2 through 18 years who have not previously received hepatitis A vaccine
    • 2-dose series at 0, 6–18 months (Vaqta)
    • 2-dose series at 0, 6–12 months (Havrix)
    • Adolescents age 18 years may receive the combined Hepatitis A and Hepatitis B vaccine Twinrix as a 3 dose series (0, 1, and 6 months) or a 4 dose series (0, 7, and 21-20 days, followed by a booster dose at 12 months)
  • Adults ages 19 years or older with risk factors
    • 2-dose series at 0, 6–18 months (Vaqta)
    • 2-dose series at 0, 6–12 months (Havrix)
    • 3-dose series at 0, 1, 6 months (Twinrix)
    • 3-dose series with doses at 0, 7, 21–30 days, and booster 12 months after dose 1 (Twinrix, accelerated)
  • The pediatric formulations of Havrix and Vaqta vaccines are approved for persons ages 12 months through 18 years. The adult formulations are approved for persons ages 19 years or older. Both vaccines are approved as a 2-dose series. The second dose of Vaqta is administered 6 through 18 months after the first dose, and the second dose of Havrix is administered 6 through 12 months after the first dose.
  • ~ Hepatitis A-Hepatitis B (Twinrix) is licensed for persons ages 18 years or older and administered as a 3-dose series at 0, 1, and 6 months. The first and second doses should be separated by at least 4 weeks, and the second and third doses should be separated by at least 5 months. Twinrix is approved for persons ages 18 years or older and can be used in persons in this age group with indications for both hepatitis A and hepatitis B vaccines. Twinrix is also approved using an alternative schedule with doses at 0, 7, and 21–30 days and a booster dose 12 months after the first dose.

    Reference: https://www.cdc.gov/vaccines/pubs/pinkbook/hepa.html#virus