Hepatitis A is a viral infection which affects the human liver. The hepatitis A virus is usually ingested via contaminated food or water and is endemic to many countries where sanitation and access to safe food and water is poor.

Hepatitis B is a liver infection caused by a virus that is spread through blood, semen and vaginal fluids. The severity of the resulting illness can range from mild to fatal. Although the infection may only last for a few months, it can remain long term.