Hepatitis A, B, and C are three completely different viruses. They are alike in that they all affect the liver and cause similar symptoms. However, that is where the similarity ends.

The most common way that people get hepatitis A virus (HAV) is when they eat or drink contaminated food or water. This usually happens when food has been handled or prepared by someone who has hep A. If the handler didn’t wash their hands well, a tiny amount of feces can get into the food. You can only get hep A once, it does not become chronic, and there is a vaccine for it.

Hepatitis B virus (HBV) is easily spread via hep B–positive blood, semen or other body fluid. Pregnant women who have hep B can also transmit the virus to their babies, usually during birth. Most adults who have hep B only get it once and don’t have lasting problems. However, some adults and most children who are HBV positive will always carry the virus. Chronic hep B is a potentially serious liver disease that can be treated but not cured. There is a vaccine to protect against it.

Hepatitis C virus (HCV) is spread by contact with hep C–positive blood. It’s rarely passed sexually, although men who have sex with men are at increased risk. The mother-to-child hep C transmission rate is much lower than it is for hep B. HCV usually becomes chronic, but not always. There is a cure for hep C that works most of the time. There is no hep C vaccine.