What Is Hepatitis A? Symptoms, Causes, Diagnosis, Treatment, and Prevention

Hepatitis is an inflammation of the liver, an organ with several important functions.

Your liver converts dietary nutrients into useful substances and breaks down toxins and chemicals.

Hepatitis A is a type of hepatitis caused by the hepatitis A virus (HAV). It’s generally acquired through consuming contaminated food or water but can also be spread from person to person and is highly contagious. (1)

Numerous other types of viral and nonviral hepatitis also exist, including hepatitis B, hepatitis C, alcohol-related hepatitis, and nonalcoholic steatohepatitis, which is caused by a buildup of fat in the liver.

The hepatitis A virus is passed between people through the “fecal-oral route,” which can occur: (2)

• When an infected person touches objects or food after going to the bathroom and failing to wash his hands properly
• When someone doesn’t wash properly after handling diapers or cleaning up the stool of an infected person
• During sex with an infected person, particularly if it involves direct or indirect anal-oral contact, or anal sex in which sanitary measures aren’t taken afterward

An infected person does not have to have symptoms to spread the virus. (1)

Many U.S. states have reported hepatitis A outbreaks in recent years among people who use illegal drugs and people who are homeless or have unstable housing. In these outbreaks, the virus is spread primarily person-to-person.

You can also get hepatitis A by ingesting food or water contaminated with feces containing HAV. (1)

Common sources of HAV transmission include fruits, vegetables, shellfish, ice, and water. (1)

This mode of transmission is far less common in the United States and other developed countries, which have better sanitation measures in place, such as treating the water supply with chlorine or chloramine. (3)

You cannot get HAV through casual contact with an infected person, such as through hugging or even being coughed or sneezed on. (3)

Babies are not believed to get HAV from breast milk. (4)

You are at an increased risk for hepatitis A if you: (1)

• Live in or travel to a developing country where hepatitis A is common
• Live with someone who has hepatitis A
• Have oral-anal sexual contact with someone who is infected
• Are a man who has sex with men
• Use illegal drugs, including those that aren’t injected
• Have hemophilia or other disorders that affect blood clotting
• Work in the healthcare, food, or sewage industries

For the majority of people, symptoms of hepatitis A last less than two months. In about 10 to 15 percent of people, the symptoms of HAV can last up to six months. (1)

People are most contagious soon after they get the infection, one to two weeks before symptoms appear. Healthy adults are no longer contagious two weeks after the illness begins, while children and people who have weak immune systems can remain contagious for up to six months, according to the American Academy of Family Physicians. (7)

After a person has HAV and recovers, they can never get the infection again; they are immune for life. (8)

While most cases of hepatitis A clear up on their own, in rare cases, HAV can lead to complications.

Liver Failure

Hepatitis A infection can lead to acute liver failure, especially in older people and people who have other liver diseases or risk factors for liver disease. (8)

In liver failure, the liver is losing or has lost the ability to perform its usual functions, which include helping to fight infection, cleaning the blood, aiding in food digestion, and storing energy. Liver failure is life-threatening and requires urgent medical care. (14)

Guillain-Barre syndrome (GBS)

Guillain-Barré syndrome is a rare but life-threatening disease where the immune system attacks the peripheral nervous system. In very rare cases, hepatitis A can cause GBS. (15)

Pancreatitis

Researchers have noted an association between hepatitis A infection and acute pancreatitis, although it is rare. (16) In acute pancreatitis, the pancreas becomes inflamed, causing such symptoms as sharp pain in the abdomen, fever, vomiting, elevated heart rate, and a swollen abdomen. Acute pancreatitis is a medical emergency, and anyone with symptoms should seek help immediately.

The best way to prevent hepatitis A is through vaccination. Research suggests that Black Americans born in the United States and Asians and Hispanics born outside but living in the United States are less likely to have been vaccinated for hepatitis A compared with white people. (18)

A number of organizations can provide more information about hepatitis A, including updates on local outbreaks.

Centers for Disease Control and Prevention (CDC)

The government agency provides information for both healthcare providers and the public, including a list of questions and answers about hepatitis A.

World Health Organization (WHO)

This organization focuses on improving health around the world. It provides guidance, resources, and recommendations about diseases, including hepatitis A.

Additional reporting by Becky Upham.