Hepatitis is an inflammation of the liver. The viruses known as hepatitis A, hepatitis B, and hepatitis C are among the most common causes of this inflammation.
There are two other known viral types, D and E, but they are rare. Hepatitis can also be caused by other viruses, certain medications, some autoimmune conditions, and long-term, heavy use of alcohol.
Hepatitis A often clears on its own without any treatment. Inflammation caused by hepatitis B or C may become chronic and lead to long-term liver damage and other complications.
When a hepatitis virus gets into the bloodstream and attacks liver cells, the body’s immune system responds to fight it. Temporary inflammation is part of this response. But if inflammation persists for months or years, it can damage or even destroy liver cells.
Liver damage can prevent the body from processing essential nutrients and from ridding the body of toxins. Without treatment, viral hepatitis can lead to scarring of the liver, also called cirrhosis, which interferes with liver function. Untreated hepatitis B or C can also lead to liver cancer.
Hepatitis A, B, and C are each caused by a specific type of hepatitis virus. All of these viruses are contagious. Hepatitis A can be spread through contaminated food, water, or personal contact with an infected person. Hepatitis B and C spread through contact with bodily fluids such as blood or semen. These viruses can affect people of any age, including newborn babies if the mother passes the virus to her child during birth.
Each type of hepatitis has distinct characteristics, and your doctor makes important decisions about treatment based on the type of virus affecting you.
Hepatitis A is inflammation of the liver caused by the hepatitis A virus. Symptoms may not appear for weeks after infection, and some people have no symptoms at all.
This disease can be spread from one person to another even before symptoms develop and up to one week after symptoms are evident. Hepatitis A can be spread through water and food that has been contaminated by microscopic amounts of stool containing the virus. This is more common in areas that have poor sanitation. Hepatitis A can also pass from person to person during unprotected sex.
Symptoms of hepatitis A include flu-like symptoms, such as fever, nausea, loss of appetite, and diarrhea. Hepatitis A may also cause jaundice, a condition that makes the skin and eyes look yellow and causes stool to become light in color and urine to become dark.
Hepatitis A is a short-lived, or acute, disease. When symptoms develop, they may cause severe illness requiring hospitalization and intravenous fluids.
In most people, the body overcomes the virus on its own after a few weeks or months. Occasionally, a person feels ill again a few months later and then gets better, usually for good after this second flare-up.
To protect yourself from hepatitis A, doctors recommend vaccination before traveling to a country where hepatitis A is common and avoiding easily contaminated food items. These include fresh vegetables or fruit (unless it can be peeled), raw shellfish, tap water, and ice cubes.
Hepatitis B is liver inflammation caused by the hepatitis B virus. People infected with the virus may or may not have symptoms but can still transmit the virus to others. Symptoms include jaundice, loss of appetite, nausea, vomiting, diarrhea, and muscle aches.
The infection may be acute, meaning short lived, or chronic, which means it persists for a long time, even if symptoms never appear. Hepatitis is considered chronic if it lasts longer than six months.
In most people, the body fights the hepatitis B virus within a few months without any permanent liver damage. In some, though, hepatitis B becomes a long-term illness and can lead to liver damage or liver cancer.
Hepatitis B is spread through contact with bodily fluids, such as saliva, blood, and semen, or with a contaminated object, such as a toothbrush or razor, where the virus can live for days.
Certain factors increase the risk of infection. These include sharing needles when injecting drugs, having unprotected sex, having a tattoo or body piercing done by someone who doesn’t use clean needles, men having sex with other men, traveling to countries where hepatitis B is common, being on long-term dialysis, and sharing items such as a toothbrush or razor with someone who is infected.
Hepatitis C is liver inflammation caused by the hepatitis C virus. Often, this disease doesn’t cause symptoms, and a person may live with hepatitis C for years or decades without knowing it.
Hepatitis C is contagious and can cause serious liver damage even if a person never has symptoms. Without treatment, hepatitis C may lead to cirrhosis, which is scarring of the liver, and liver cancer.
If symptoms develop, they include fatigue, joint pain, muscle weakness, and jaundice.
Hepatitis C is spread from person to person, primarily through contact with contaminated blood. According to the U.S. Centers for Disease Control and Prevention, sharing needles during intravenous drug use is now the most common way the hepatitis C virus is spread in the United States.
Other risk factors include having unprotected sex with multiple partners, sharing devices such as straws when snorting a drug through the nose, and having a tattoo or piercing done by someone who uses unclean equipment.
Having received a blood transfusion before 1992 is also a risk factor for hepatitis C, and our doctors encourage anyone who had a transfusion before that time to be screened.
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