Hepatitis A: The One You Can Be Vaccinated Against

Of the three common hepatitis viruses, A is the one that does not become chronic, does not need antiviral treatment, and can be prevented outright with a vaccine. It is also the one most likely to arrive through something you ate.

That combination makes it unusual: an infection where prevention is genuinely simple and treatment is mostly waiting.

How it differs from B and C

The three hepatitis viruses, compared

	Hepatitis A	Hepatitis B	Hepatitis C
Mainly spread by	Food, water, close contact	Blood, sex, birth	Blood
Becomes chronic	No	Sometimes, depending on age at infection	Often
Vaccine available	Yes	Yes	No
Usual treatment	Supportive care only	Monitoring, antivirals for some	A short course that usually cures it
Long-term liver damage	Very rarely	Possible	Common if untreated
After recovery	Immune for life	Depends on the picture	Cured, but reinfection is possible

Our articles on what a positive hepatitis B test means and hepatitis C treatment cover the other two. The most important line in that table is the first: hepatitis A spreads by a completely different route, which is why the precautions are completely different.

How it spreads

The virus is shed in stool and reaches other people through contaminated food or water, or through close personal contact. That sounds unpleasant and it is simply how it works — it takes microscopic quantities and unwashed hands.

• Food handled by someone infectious who did not wash their hands
• Shellfish from contaminated water, eaten raw or undercooked
• Fresh produce irrigated or washed with contaminated water
• Household contact with someone infected
• Sexual contact, particularly oral-anal contact
• Travel to areas where it is common; see travel vaccines and how far ahead to plan

People are most infectious in the two weeks before symptoms appear, which is why outbreaks spread before anyone knows there is one.

What the illness is like

Symptoms appear two to seven weeks after exposure and typically build over days: fatigue, nausea, poor appetite, aching, sometimes fever and abdominal discomfort. Jaundice — yellowing of the eyes and skin, dark urine, pale stools — follows in many adults.

Two things surprise people. The first is how long it lasts: several weeks is usual and a couple of months is not unusual, with fatigue outlasting everything else, as in our article on recovering after a serious infection. The second is that young children often have no symptoms at all while remaining fully infectious.

Adults tend to be more unwell with it than children, and the illness is more likely to be severe in people over fifty and in anyone whose liver is already under strain from another cause. That is the main reason hepatitis A is taken seriously in an adult even though it does not become chronic.

Treatment is supportive, with one important exception

There is no antiviral for hepatitis A. Treatment is rest, fluids, and avoiding anything that adds to the liver’s workload — alcohol above all, and a review of your regular medications with a clinician, since several are processed by the liver. Our article on antibiotics and your other medicines covers the general principle.

The exception is exposure. If you have been in contact with someone infectious and are not immune, vaccine or immune globulin given promptly can prevent the illness altogether — and “promptly” means within two weeks. That is a same-week phone call, not a routine appointment.

How it is diagnosed, and why outbreaks are investigated

Diagnosis is a blood test. Liver enzymes are usually markedly raised, and a specific antibody test separates recent infection from past infection or vaccination. Our article on what a positive hepatitis B test means explains the same logic in more detail, since hepatitis testing generally reports several results that only mean something read together.

Hepatitis A is reportable to public health authorities, which is not a judgement on anyone. It is because a single case in a food handler or a shared setting can become many cases, and because vaccinating contacts quickly stops that happening. Recent US outbreaks have concentrated in particular communities rather than in the general food supply, which is why the vaccine recommendations name specific groups.

The vaccine, and who should have it

The hepatitis A vaccine is safe, effective and long-lasting. It is given as two doses six months apart, and a single dose provides good protection within a few weeks — which is why it is worth having even shortly before travel.

• All children, as part of the routine schedule
• Travelers to most of the world outside North America and Western Europe
• Men who have sex with men
• People who use drugs, injected or otherwise
• People experiencing homelessness, among whom outbreaks have been common
• Anyone with chronic liver disease, including hepatitis B or hepatitis C
• Close contacts of someone with hepatitis A
• Anyone who simply wants to be protected, which is a sufficient reason

Our article on which adult vaccines you need covers where this sits in the adult schedule. The practice runs a travel medicine service, and you can reach us through the contact page.

If you have it, protecting everyone else

• Wash hands thoroughly after using the bathroom and before handling food
• Do not prepare food for other people while infectious
• Do not share towels, utensils or drinks
• Stay off work for the period your clinician advises, which matters most in food handling, healthcare and childcare
• Tell close contacts promptly, so they can be vaccinated in time
• Avoid alcohol entirely until liver tests have returned to normal

Public health departments take an interest in hepatitis A precisely because prompt vaccination of contacts prevents onward cases. Being contacted by them is routine rather than alarming.

Frequently asked questions