Anju Goel, MD, MPH, is a board-certified physician who specializes in public health, communicable disease, diabetes, and health policy.
Hepatitis is a disease caused by inflammation of the liver. It usually results from infection with a virus, but there are also non-viral forms of the disease, including hepatitis brought on by the use of certain drugs, alcohol abuse, and autoimmune disease.
Hepatitis can be acute (lasting just a few weeks to a few months), cause few, if any, symptoms, and resolve on its own. It can also be chronic, meaning inflammation persists for six months or longer. Chronic hepatitis can lead to serious and even life-threatening complications, such as cirrhosis, liver cancer, and liver failure.
There are effective vaccines for two of the viral forms: hepatitis A and hepatitis B.
Five viruses can cause hepatitis: hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), hepatitis E virus (HEV). Some forms are transmitted by contaminated food, water, and stool. Others are primarily transmitted by blood or bodily fluids. Preventative measures include washing your hands, using condoms, avoiding shared needles, and vaccination.
Hepatitis A and E mainly spread through contaminated food or water. Hepatitis B spreads through blood and bodily fluids and is spread during sex, needle sharing, and from a pregnant woman to her baby. Hepatitis C mostly spreads through blood. Hepatitis D also spreads through blood and body fluids and only infects those already infected with Hepatitis B.
The causes can be broadly categorized as infectious, metabolic, or autoimmune. Viral hepatitis, especially hepatitis B and C, is the most common form. There is also autoimmune hepatitis that may be caused by a combination of genetic and lifestyle factors and toxic hepatitis caused by excessive alcohol use, toxic chemicals, or drugs.
Hepatitis B and hepatitis C are the most common viral causes of chronic hepatitis and liver damage. Hepatitis B is particularly dangerous for infants. Approximately 90% of infants with HBV develop chronic infections. There is no cure for HBV, but there is a vaccine to prevent it.
Viral infections often clear on their own. If the condition becomes chronic, there is no cure for Hepatitis B. Medications, especially direct-acting antivirals, are able to cure hepatitis C in most cases, yet may be cost prohibitive to many people. Hepatitis A or E resolve on their own and do not result in chronic illness.
Chronic hepatitis is when your body isn’t able to fight off a viral infection and inflammation lasts for more than six months. Hepatitis B and C can be acute or chronic. Hepatitis A and E are acute and clear without becoming chronic. Chronic hepatitis can lead to complications such as cirrhosis, liver cancer, and liver failure.
A severe scarring of the liver. The scarring is called fibrosis. As the scar tissue builds, the liver isn’t able to function or repair itself properly. The most common causes of cirrhosis are alcohol-related liver disease, hepatitis B, hepatitis C, and non-alcoholic fatty liver disease.
Also called fatty liver disease, hepatic steatosis is a buildup of fat in the liver. It can be caused by excessive alcohol use or it can be linked to obesity, type 2 diabetes, and diet. If caught early, hepatitis steatosis can be reversed with lifestyle changes. If it goes untreated and progresses, it can lead to cirrhosis and liver failure.
An infection caused by a virus. Viruses are microscopic organisms that invade cells and use them to multiply. Most viruses are spread from person to person through respiratory droplets, fecal-oral contact, or contact with blood or other bodily fluids.
National Cancer Institute. Breast Cancer Risk in American Women. Updated October 3, 2019.
National Institute of Diabetes and Digestive and Kidney Diseases. What is viral hepatitis? Updated May 2017.