Hepatitis A is caused by the hepatitis A virus, which is spread in the poo of someone with the infection.
Most infections occur in parts of the world where sanitation and food hygiene standards are poor, although there's a small risk of becoming infected in the UK.
How hepatitis A is spread
You can get hepatitis A from:
eating food prepared by someone with the infection who has not washed their hands properly, or who's washed them in water contaminated with sewage
drinking contaminated water, including ice cubes
eating raw or undercooked shellfish from contaminated water
close contact with someone who has hepatitis A
having sex with someone who has the infection, particularly if you touch their anus with your fingers, mouth or tongue
injecting drugs using equipment contaminated with the hepatitis A virus
Someone with hepatitis A is most infectious from around 2 weeks before they start to develop symptoms until about a week afterwards.
Hepatitis A is found worldwide, but areas where it's most widespread include:
sub-Saharan and northern Africa
the Indian subcontinent (particularly India, Bangladesh, Pakistan and Nepal)
some parts of the Far East (excluding Japan)
the Middle East
South and Central America
To find out about the potential health risks in a specific country, see country information on the Travel Health Pro website.
People at risk of hepatitis A in the UK
Although the chances of getting hepatitis A in the UK are much smaller than in other parts of the world, certain groups have an increased risk.
close contacts of someone with hepatitis A
men who have sex with other men
people who inject illegal drugs
people who may be exposed to hepatitis A through their job – this includes sewage workers, people who work for organisations where levels of personal hygiene may be poor, such as a homeless shelter, and people working with monkeys, apes and gorillas (these animals may be infected with hepatitis A)
People in these groups are usually advised to have the hepatitis A vaccine to minimise their risk of infection.