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 inflammation and affect your liver's ability to function.
You're most likely to contract hepatitis A from contaminated food or water or from close contact with someone who's infected. Mild cases of hepatitis A don't require treatment, and most people who are infected recover completely with no permanent liver damage.
Practicing good hygiene, including washing hands frequently, is one of the best ways to protect against hepatitis A. Vaccines are available for people most at risk.
Symptoms of the Hepatitis A
Hepatitis A signs and symptoms, which typically don't appear until you've had the virus for a few weeks, may include:
- Nausea and vomiting
- Abdominal pain or discomfort, especially in the area of your liver on your right side beneath your lower ribs
- Clay-colored bowel movements
- Loss of appetite
- Low-grade fever
- Dark urine
- Joint pain
- Yellowing of the skin and eyes (jaundice)
If you have hepatitis A, you may have a mild illness that lasts a few weeks or a severe illness that lasts several months. Not everyone with hepatitis A develops signs or symptoms.
Causes of the Hepatitis A
The hepatitis A virus, which causes the infection, usually is spread when a person ingests even tiny amounts of contaminated fecal matter. The hepatitis A virus infects liver cells and causes inflammation. The inflammation can impair liver function and cause other signs and symptoms of hepatitis A.
Hepatitis A virus can be transmitted several ways, such as:
- Eating food handled by someone with the virus who doesn't thoroughly wash his or her hands after using the toilet
- Drinking contaminated water
- Eating raw shellfish from water polluted with sewage
- Being in close contact with a person who's infected — even if that person has no signs or symptoms
- Having sex with someone who has the virus
You're at increased risk of hepatitis A if you:
- Travel or work in regions with high rates of hepatitis A
- Attend child care or work in a child care center
- Are a man who has sexual contact with other men
- Are HIV positive
- Have a clotting-factor disorder, such as hemophilia
- Use injected or noninjected illicit drugs
- Live with another person who has hepatitis A
- Have oral-anal contact with someone who has hepatitis A
Complications of the Hepatitis A
Unlike other types of viral hepatitis, hepatitis A does not cause long-term liver damage, and it doesn't become chronic.
In rare cases, hepatitis A can cause loss of liver function that occurs suddenly, especially in older adults or people with chronic liver diseases. Acute liver failure requires hospitalization for monitoring and treatment. Some people with acute liver failure may require a liver transplant.