Overview

Hepatitis A is a highly contagious liver infection caused by the hepatitis A virus. The virus is one of several types of hepatitis viruses that cause liver inflammation and affect your liver's ability to function.

You're most likely to get hepatitis A from contaminated food or water or from close contact with a person or object that's infected. Mild cases of hepatitis A don't require treatment. Most people who are infected recover completely with no permanent liver damage.

Practicing good hygiene, including washing hands frequently, can prevent the spread of the virus. The hepatitis A vaccine can protect against hepatitis A.

Symptoms

Hepatitis A symptoms typically appear a few weeks after you've had the virus. But not everyone with hepatitis A develops symptoms. If you do, symptoms can include:

  • Unusual tiredness and weakness
  • Sudden nausea and vomiting and diarrhea
  • Abdominal pain or discomfort, especially on the upper right side beneath your lower ribs, which is over your liver
  • Clay- or gray-colored stool
  • Loss of appetite
  • Low-grade fever
  • Dark urine
  • Joint pain
  • Yellowing of the skin and the whites of your eyes (jaundice)
  • Intense itching

These symptoms may be relatively mild and go away in a few weeks. Sometimes, however, hepatitis A results in a severe illness that lasts several months.

When to see a doctor

Make an appointment with your health care provider if you have symptoms of hepatitis A.

Getting the hepatitis A vaccine or an injection of an antibody called immunoglobulin within two weeks of exposure to the hepatitis A virus may protect you from infection.

Ask your health care provider or your local health department about receiving the hepatitis A vaccine if:

  • You traveled recently to areas where the virus is common, particularly Mexico, Central America and South America or to areas with poor sanitation
  • You ate at a restaurant with a hepatitis A outbreak
  • You live with someone who has hepatitis A
  • You recently had sexual contact with someone who has hepatitis A

Causes

Hepatitis A is caused by a virus that infects liver cells and causes inflammation. The inflammation can affect how your liver works and cause other symptoms of hepatitis A.

The virus spreads when infected stool, even just tiny amounts, enters the mouth of another person (fecal-oral transmission). You may get hepatitis A when you eat or drink something contaminated with infected stool. You may also get the infection through close contact with a person who has hepatitis A. The virus can live on surfaces for a few months. The virus does not spread through casual contact or by sneezing or coughing.

Here are some of the specific ways the hepatitis A virus can spread:

  • Eating food handled by someone with the virus who doesn't thoroughly wash hands after using the toilet
  • Drinking contaminated water
  • Eating food washed in contaminated water
  • Eating raw shellfish from water polluted with sewage
  • Being in close contact with a person who has the virus — even if that person has no symptoms
  • Having sexual contact with someone who has the virus

Risk factors

You're at increased risk of hepatitis A if you:

  • Travel or work in areas of the world where hepatitis A is common
  • Live with another person who has hepatitis A
  • Are a man who has sexual contact with other men
  • Have any type of sexual contact with someone who has hepatitis A
  • Are HIV positive
  • Are homeless
  • Use any type of recreational drugs, not just those that are injected

Complications

Unlike other types of viral hepatitis, hepatitis A does not cause long-term liver damage, and it doesn't become an ongoing (chronic) infection.

In rare cases, hepatitis A can cause a sudden (acute) loss of liver function, especially in older adults or people with chronic liver diseases. Acute liver failure requires a stay in the hospital for monitoring and treatment. Some people with acute liver failure may need a liver transplant.

Prevention

The hepatitis A vaccine can prevent infection with the virus. The vaccine is typically given in two shots. The first shot is followed by a booster shot six months later. The hepatitis A vaccine can be given in a combination that includes the hepatitis B vaccine. This vaccine combination is given in three shots over six months.

The Centers for Disease Control and Prevention recommends the hepatitis A vaccine for the following people:

  • All children at age 1 year, or older children who didn't receive the childhood vaccine
  • Anyone age 1 year or older who is homeless
  • Infants ages 6 to 11 months traveling to parts of the world where hepatitis A is common
  • Family and caregivers of adoptees from countries where hepatitis A is common
  • People in direct contact with others who have hepatitis A
  • Laboratory workers who may come into contact with hepatitis A
  • Men who have sex with men
  • People who work or travel in parts of the world where hepatitis A is common
  • People who use any type of recreational drugs, not just injected ones
  • People with chronic liver disease, including hepatitis B or hepatitis C
  • Anyone wishing to obtain protection (immunity)

If you're concerned about your risk of hepatitis A, ask your health care provider if you should be vaccinated.

Follow safety precautions when traveling

If you're traveling to parts of the world where hepatitis A outbreaks occur, take these steps to prevent infection:

  • Wash all fresh fruits and vegetables in bottled water and peel them yourself. Avoid pre-cut fruit and vegetables.
  • Don't eat raw or undercooked meat and fish.
  • Drink bottled water and use it when brushing your teeth.
  • Avoid all beverages of unknown purity. The same goes for ice.
  • If bottled water isn't available, boil tap water before drinking it or using it to make ice.

Practice good hygiene

Thoroughly wash your hands often, especially after using the toilet or changing a diaper and before preparing food or eating.

By Mayo Clinic Staff