There are five major types of viral hepatitis, or liver inflammation, plus a couple of rare types.

Hepatitis A is transmitted through food or water contaminated with feces. It is an acute form of hepatitis, meaning that it doesn’t cause chronic, or long-term, infection. It usually resolves on its own, but in some cases, it can cause fatal liver disease. If you have had hep A once, you cannot be infected with the virus again. 

Hepatitis B is a blood-borne infection that can be transmitted through sex, from mother to child during pregnancy and via shared needles or personal items, such as razors. About 90% of people infected as infants develop chronic infection, but most adults clear the virus naturally and recover. If you have had hepatitis B once, you cannot get it again. 

Hepatitis C is also a blood-borne infection that is transmitted in similar ways. About a quarter of adults clear the virus naturally, but the rest develop chronic infection. It is possible to get infected with hepatitis C again after natural clearance or treatment.

Hepatitis D, or delta, is a defective virus that occurs only in people with hepatitis B. Coinfection with both hepatitis B and D can lead to more severe liver disease.

Hepatitis E is transmitted through contaminated food or water, like hep A. It usually resolves on its own, but it can cause more serious disease in pregnant women.

Hepatitis symptoms include fatigue, nausea, loss of appetite, pain in the upper right abdomen, yellowing of the skin and eyes (jaundice), dark urine, pale stools and elevated ALT and AST liver enzymes. Many people with hepatitis B or C have no early symptoms and are not aware that they have the virus. But over years or decades, they can cause serious liver disease, including cirrhosis, liver cancer and liver failure.

Hepatitis A and B can be prevented with vaccines, which are recommended for all infants and for adults at risk; preventing hep B also prevents hep D. There is no vaccine yet for hepatitis C.

Hepatitis A and E usually resolve on their own. Hepatitis B and D can be treated with antivirals, but they usually cannot be cured. Hepatitis C can be treated with well-tolerated direct-acting antivirals for two or three months, and almost everyone can be cured.