Hepatitis A is a liver infection caused by a virus that's spread in the poo of an infected person.
It's uncommon in the UK, but certain groups are at increased risk. This includes travellers to parts of the world with poor levels of sanitation, men who have sex with men, and people who inject drugs.
Hepatitis A can be unpleasant, but it's not usually serious and most people make a full recovery within a couple of months.
Some people, particularly young children, may not have any symptoms. But hepatitis A can occasionally last for many months and, in rare cases, it can be life-threatening if it causes the liver to stop working properly (liver failure).
A hepatitis A vaccine is available for people at a high risk of infection.