Prevention & care

Hepatitis A: spread, recovery and prevention after exposure

7 sources · Latest source check 2026-10-13 UTC

On this page

Hepatitis means inflammation of the liver; hepatitis A is the form caused by hepatitis A virus, or HAV. Infection usually causes a short-term illness, although severity varies. The virus spreads when it is swallowed, often through close personal contact or contaminated food or water. It is a different virus from hepatitis B or C.[1]

Infection, clinical illness and complications are different categories

Asymptomatic infection means virus is present without noticeable illness. Symptomatic acute disease may involve fatigue, poor appetite, nausea, dark urine and jaundice. Prolonged or relapsing illness can continue for months; a recurrence of symptoms is different from a lifelong chronic HAV infection. Rare fulminant hepatitis means acute liver failure and is a severe complication, not the usual course.[6]

Food contamination is one route, not the whole explanation

HAV is spread through swallowing very small amounts of virus. Food or water can become contaminated, while close contact also allows spread. Someone may transmit infection before realizing they are ill. Handwashing after bathroom use or changing diapers and before preparing food reduces opportunities for transmission; outward cleanliness or absence of jaundice does not prove a person cannot spread HAV.[1]

The interval after exposure makes recall difficult

Symptoms may begin several weeks after exposure rather than immediately after a particular meal. Fever, digestive symptoms and jaundice can have other causes, and children often have less noticeable illness than adults. Seek medical assessment for suspected hepatitis rather than using a symptom list to decide which virus is responsible. A known exposure matters even before symptoms occur.[2]

Antibodies to recent infection and past immunity are different tests

IgM anti-HAV supports recent or current infection in the appropriate clinical context. IgG anti-HAV indicates immunity from previous infection or vaccination. Total antibody measures do not by themselves distinguish these situations. CDC cautions against indiscriminate IgM testing: false positivity or cross-reactivity can occur. Clinical history and exposure remain important when interpreting a result.[3]

Routine protection and postexposure protection have different timing

US guidance recommends childhood vaccination and vaccination for specified risk groups, including chronic liver disease; any adult requesting protection may be vaccinated. Single-antigen products protect against HAV, while an adult combination product covers hepatitis A and B. Their schedules and age restrictions differ. Completing the relevant course provides longer-term protection; country-specific recommendations can differ.[4]

After a relevant exposure, contact a clinician or public-health service promptly. Vaccine, immune globulin or both may prevent illness when given within two weeks; selection depends on age, health and prior vaccination. Waiting for a blood-test result or for jaundice to appear can miss that prevention window. This is a time-sensitive clinical decision, not a home medicine recipe.[2]

Supportive care is active care even without a specific antiviral

Most people recover, but supportive care may be needed for hydration, nutrition and monitoring; severe illness may require hospital care. No specific antiviral is routinely used to cure hepatitis A. Relapse and the rare severe complication are reasons to reassess a changing course. An average recovery time does not establish that ongoing symptoms in one person are safe to ignore.[5]

Evidence & uncertainty

Hepatitis A does not ordinarily become a chronic infection like hepatitis B or C can. That distinction does not mean every episode is harmless: older people and those with existing liver disease can face greater risks, and outbreaks require timely public-health prevention.[5][7]

Selected-source overview · Independent review pending

Published questions

Does hepatitis A become chronic hepatitis?

Selected-source overview · Independent review pending. Read the evidence context.

It does not ordinarily cause chronic infection. Prolonged or relapsing symptoms are different from lifelong infection with another hepatitis virus.[6]

Evidence behind this answer

Pink Book Chapter 9: Hepatitis A
agency clinical guidance · 2024
Selected relevant page text, guideline passages, or publication abstract inspected · Clinical spectrum, prolonged/relapsing disease and complication context