What Is Hepatitis? Hepatitis (pronounced: hep-uh-TIE-tiss) is an inflammation of the liver. The liver, in the right side of the abdomen, is an important organ that processes nutrients, metabolizes medicines, and helps clear toxins from the body. Most cases of hepatitis are caused by a virus. The three most common hepatitis viruses are hepatitis A, hepatitis B, and hepatitis C. (Hepatitis viruses D and E are rare in the United States.) Hepatitis that's not caused by a virus can happen from things such as: a bacterial infection liver injury caused by a toxin (poison) liver damage caused by interruption of the organ's normal blood supply liver damage caused by interruption of the flow of bile through the liver abdominal trauma in the area of the liver an attack on the liver by the body's own immune system (called autoimmune hepatitis) a problem with the liver itself What Is Hepatitis A? Hepatitis A virus (HAV) is contagious, usually spreading to others through food, drink, or objects contaminated by feces (poop) containing HAV. The hepatitis A vaccine has helped to make the infection rare in the United States and other developed countries. Although a hepatitis A infection can cause severe symptoms, unlike some other hepatitis viruses, it rarely leads to long-lasting liver damage. People who have recovered from a hepatitis A infection have immunity to the virus and won't get it again. Read more about hepatitis A. What Is Hepatitis B? Hepatitis B is a more serious infection. It can lead to cirrhosis (permanent scarring) of the liver, liver failure, or liver cancer, causing severe illness and even death. Hepatitis B virus (HBV) spreads from person to person through blood or other body fluids. It also can be passed from an infected mother to her unborn baby. In the United States, this most commonly happens through unprotected sex with someone who has the disease or from injecting drugs with shared needles that aren't sterilized. The hepatitis B vaccine is approved for people of all ages to prevent HBV infection. Read more about hepatitis B. What Is Hepatitis C? Like hepatitis B, the hepatitis C virus (HCV) spreads from person to person through blood or other body fluids, and can lead to cirrhosis or liver cancer. The most common way people become infected is by sharing drug paraphernalia such as needles and straws. People also can get hepatitis C from unprotected sex with an infected partner. And it can be passed from an infected mother to her unborn baby. Hepatitis C is the most serious type of hepatitis. It's now one of the most common reasons for liver transplants in adults. Scientists have been trying for decades to develop a hepatitis C vaccine, but none has been successful yet. Fortunately, medicines can now treat people with hepatitis C and cure them in most cases. Read more about hepatitis C. Back to Articles Related Articles Hepatitis A Hepatitis A is a contagious liver infection caused by the hepatitis A virus (HAV). The hepatitis A vaccine has helped to make the infection rare in the United States. Read More Hepatitis B Hepatitis B can move from one person to another through blood and other body fluids. For this reason, people usually get it through unprotected sex or by sharing needles. Read More Can I Donate Blood After Having Hepatitis B? Find out what the experts have to say. Read More Hepatitis C The hepatitis C virus (HCV) spreads through blood or other body fluids, and can lead to cirrhosis or liver cancer. The most common way people become infected is by sharing drug paraphernalia. Read More Immunizations Missing out on shots puts you at more serious risk than you might think. That one little "ouch" moment protects you from some major health problems. Read More Blood Test: Liver Function Tests If your liver isn't working properly, it can affect your overall health. Find out why doctors do liver function tests and what's involved for teens. Read More STDs (Sexually Transmitted Diseases) You've probably heard lots of discouraging news about sexually transmitted diseases. The good news is that STDs can be prevented. Find out how to protect yourself. Read More Are Steroids Worth the Risk? Will using steroids transform you into the most powerful athlete your coach has ever seen? Read this article to learn the facts on steroid use. Read More Body Piercing Wondering whether you should pierce one of your precious parts? Read about what to expect. Read More Tattoos What's the safest way to get a tattoo? Does it hurt? What can go wrong? Knowing the facts will help you decide whether a tattoo is a good idea for you. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.