Hepatitis A is a liver infection caused by the hepatitis A virus. You contract it almost exclusively through the fecal-oral route, meaning you swallow something that has been contaminated with microscopic amounts of stool from an infected person. This happens through contaminated food, contaminated water, or direct personal contact, and it is highly preventable with a safe and effective vaccine.
What Is the Main Way People Get Hepatitis A?
The virus lives in the stool of an infected person. It leaves the body during a bowel movement. If that person does not wash their hands properly, the virus transfers to their hands, then to objects, food, or another person’s skin.
You get infected when those contaminated particles reach your mouth. This is why the infection spreads easily in households, daycare centers, and among people who live closely together. The virus is tough. It can survive outside the body for months, depending on the surface and temperature.
Can You Get Hepatitis A From Food?
Yes. Contaminated food is one of the most common ways hepatitis A spreads. The person who handles your food may be infected and not know it. They can pass the virus to the food if they do not wash their hands after using the bathroom.
Certain foods carry higher risk. These include:
- Raw or undercooked shellfish from contaminated water
- Fresh produce like berries, lettuce, and green onions
- Any food handled by an infected person after cooking
Food can also be contaminated during growing, harvesting, or processing. Irrigation water contaminated with human waste is a known source. Freezing does not kill the virus. Neither does mild heating. Food must be cooked to an internal temperature high enough to destroy the virus, typically above 185°F (85°C) for at least one minute.
How Does Water Spread Hepatitis A?
Drinking water contaminated with human sewage can transmit the virus. This is more common in regions with poor sanitation or after flooding and natural disasters. In the United States, municipal water treatment systems are highly effective at removing the virus, so waterborne outbreaks are rare here.
Private wells are a different story. If a well is flooded or located near a failing septic system, contamination is possible. Ice made from contaminated water is also a risk. So is brushing your teeth with contaminated water when traveling.
Travelers to countries with inadequate water treatment should assume the local water is unsafe. Bottled water, boiled water, or water treated with chlorine or iodine is the safer choice.
Is Hepatitis A Sexually Transmitted?
Yes, in a specific way. The virus is not in semen or vaginal fluids. It is in stool. Sexual practices that involve oral-anal contact, sometimes called rimming, can transmit the virus directly.
Men who have sex with men have higher rates of hepatitis A infection. This is why public health agencies recommend the vaccine for this group. Anyone who engages in oral-anal contact with a partner whose vaccination status is unknown is at risk.
Good hand hygiene before and after sexual activity reduces risk. But the vaccine is the only reliable protection.
What Are the Other Routes of Transmission?
Direct person-to-person contact is a major route. This does not mean casual contact like shaking hands or sitting next to someone. It means close, sustained contact where fecal particles can transfer to your mouth.
Household contacts of an infected person are at high risk. So are caregivers who change diapers or assist with toileting. People who use illicit drugs, whether injected or not, have higher infection rates, partly due to shared equipment and partly due to hygiene conditions.
Blood transfusion is theoretically possible but extremely rare. Screening of donated blood has made this route nearly nonexistent in developed countries. The virus can also be passed from a pregnant woman to her baby, though this is uncommon.
Who Is Most at Risk for Hepatitis A?
Anyone who has not been vaccinated or previously infected can get hepatitis A. But certain groups face higher exposure:
- Travelers to countries with high infection rates
- People experiencing homelessness
- People who use drugs
- Men who have sex with men
- People with chronic liver disease
- People with clotting factor disorders
- Household contacts of adopted children from high-risk countries
People with chronic liver disease are not more likely to get infected. But if they do get infected, they are far more likely to develop severe complications, including liver failure and death.
How Long Before Symptoms Appear?
The incubation period is typically 15 to 50 days, with an average of about 28 days. During this time, you have no symptoms but can still shed the virus in your stool. You are most contagious during the two weeks before symptoms begin.
Some people, especially young children, never develop symptoms at all. They can still spread the virus to others. This makes outbreak control difficult because silent carriers do not know they are infected.
What Are the Symptoms of Hepatitis A?
Symptoms usually appear suddenly. They include:
- Fatigue and weakness
- Nausea and vomiting
- Loss of appetite
- Abdominal pain, especially in the upper right side
- Dark urine
- Clay-colored stool
- Jaundice, a yellowing of the skin and eyes
- Low-grade fever
- Joint pain
Not everyone gets all symptoms. Children under six often have no symptoms or only mild ones. Older children and adults typically have more severe symptoms. Jaundice occurs in more than 70% of symptomatic adults.
How Is Hepatitis A Diagnosed?
A blood test detects antibodies against the virus. The IgM antibody appears early in infection and indicates a current or recent infection. The IgG antibody appears later and indicates past infection or vaccination.
If you have symptoms consistent with hepatitis A, a doctor will order this blood test. The test is highly accurate. False positives are rare.
What Is the Treatment for Hepatitis A?
There is no specific antiviral medication for hepatitis A. The infection is self-limiting, meaning your immune system clears it on its own. Treatment focuses on supportive care.
Rest, adequate fluids, and avoiding alcohol are the mainstays. Acetaminophen should be used cautiously because it is processed by the liver. Some doctors recommend avoiding it entirely during acute infection. Ibuprofen and other NSAIDs may also stress the liver.
Most people recover fully within two months. About 15% of people have prolonged or relapsing symptoms lasting up to six months. Full recovery is the rule. Hepatitis A does not cause chronic liver disease, unlike hepatitis B and C.
How Can You Prevent Hepatitis A?
The hepatitis A vaccine is the most effective prevention. It is a killed virus vaccine, so it cannot cause the infection. Two doses given six to eighteen months apart provide long-term protection, likely lasting decades.
The vaccine is recommended for all children starting at age one. It is also recommended for adults at increased risk and for anyone who simply wants protection. The vaccine is safe. Serious side effects are extremely rare.
Good hand hygiene is the second line of defense. Wash hands thoroughly with soap and water after using the bathroom, changing diapers, and before preparing or eating food. Alcohol-based hand sanitizers are less effective against hepatitis A than soap and water.
When traveling to high-risk areas, follow the rule: boil it, cook it, peel it, or forget it. Avoid raw produce, tap water, and ice made from tap water.
What Should You Do If You Were Exposed?
If you have been in close contact with someone diagnosed with hepatitis A, act quickly. Post-exposure prophylaxis works best within two weeks of exposure.
Two options exist. The hepatitis A vaccine alone is preferred for healthy people aged 12 months to 40 years. Immune globulin, which provides immediate antibodies, is used for infants under 12 months, people over 40, people with weakened immune systems, and people with chronic liver disease.
Call a doctor or your local health department immediately if you think you were exposed. Do not wait for symptoms. Prophylaxis may prevent the infection entirely or make it milder.
Frequently Asked Questions
Can you get hepatitis A from kissing?
No. The virus is not spread through saliva or kissing. It spreads through the fecal-oral route, meaning contaminated food, water, or direct contact with infected stool.
How long is a person contagious with hepatitis A?
A person is most contagious during the two weeks before symptoms appear and remains contagious for about one week after symptoms start. Young children may shed the virus for longer.
Can you get hepatitis A twice?
No. Once you recover from hepatitis A, you have lifelong immunity. Your body produces antibodies that protect you from future infection.
Is hepatitis A worse than hepatitis B or C?
Hepatitis A is acute and resolves on its own without causing chronic liver disease. Hepatitis B and C can become chronic infections that cause long-term liver damage. However, hepatitis A can cause severe illness and rarely liver failure in older adults.
