Hepatitis: Types, Causes, Symptoms, Diagnosis, Treatment and Prevention

Hepatitis means inflammation of the liver. The liver is a vital organ that filters blood, processes nutrients and medicines, makes bile for digestion, produces proteins needed for blood clotting, and stores energy. When it is inflamed or damaged, it cannot do these jobs properly.

Hepatitis can be short-term (acute), lasting less than six months, or long-term (chronic), lasting six months or more. Some people recover completely, while others develop lasting liver damage such as scarring (cirrhosis), liver failure or liver cancer.

The most common cause worldwide is viral infection by five main hepatitis viruses, called A, B, C, D and E. Hepatitis can also be caused by alcohol, medicines, toxins, fat buildup in the liver and autoimmune disease.

According to the World Health Organization, about 304 million people were living with chronic hepatitis B or C in 2022, and viral hepatitis caused around 1.3 million deaths that year, mostly from cirrhosis and liver cancer. Many people with chronic hepatitis do not know they are infected, because symptoms may not appear for years.

When the liver is inflamed, liver cells can be injured or die. Over time, ongoing inflammation can cause scar tissue to replace healthy tissue. The stages of chronic liver damage are generally:

• Inflammation: The liver is inflamed but still functions normally.
• Fibrosis: Scar tissue begins to form.
• Cirrhosis: Widespread scarring changes the structure of the liver and reduces its function.
• Complications: These can include liver failure, fluid buildup in the abdomen, bleeding from swollen veins, confusion caused by toxin buildup, and liver cancer.

Early diagnosis and treatment can stop or slow this process.

Hepatitis A (HAV)

• How it spreads: Through the fecal–oral route, meaning by eating or drinking food or water contaminated with the stool of an infected person, or through close personal contact. Outbreaks are linked to poor sanitation and contaminated food or water.
• Course: Always acute. It does not become chronic.
• Incubation period: Typically 14 to 28 days.
• Outcome: Most people recover fully within weeks to a few months and develop lifelong immunity. Severe illness is more likely in older adults and people with existing liver disease. Acute liver failure is rare.
• Vaccine: Yes, a safe and effective vaccine is available.

Hepatitis B (HBV)

• How it spreads: Through blood and body fluids. Main routes are from mother to baby during birth, sexual contact, sharing needles or syringes, unsafe medical or dental procedures, and contact with infected blood in households with chronic carriers. It does not spread through casual contact such as hugging, sharing food or coughing.
• Course: Can be acute or chronic. The age at infection matters greatly. About 80% to 90% of infants infected in the first year of life develop chronic infection, compared with around 30% to 50% of children infected before age 6 and less than 5% of otherwise healthy adults.
• Incubation period: 30 to 180 days, commonly around 75 days.
• Outcome: Chronic hepatitis B can lead to cirrhosis and liver cancer. It is a leading cause of liver cancer worldwide.
• Vaccine: Yes, a highly effective vaccine is available. The first dose is recommended within 24 hours of birth.

Hepatitis C (HCV)

• How it spreads: Mainly through blood contact. This includes sharing needles or drug equipment, unsafe medical procedures, unscreened blood transfusions in the past, and, less commonly, from mother to baby or sexual contact.
• Course: After infection, roughly 15% to 45% of people clear the virus on their own within six months. The rest develop chronic infection.
• Incubation period: 2 weeks to 6 months.
• Outcome: Many people have no symptoms for decades. Chronic infection can cause cirrhosis and liver cancer.
• Vaccine: No vaccine is available, but the infection can usually be cured with modern medicines.

Hepatitis D (HDV)

• Hepatitis D only occurs in people who already have hepatitis B, because the virus needs HBV to replicate.
• It spreads through blood and body fluids.
• Co-infection or superinfection with HDV makes liver disease more severe and speeds up progression to cirrhosis.
• Preventing hepatitis B through vaccination also prevents hepatitis D.

Hepatitis E (HEV)

• How it spreads: Mostly through contaminated drinking water or undercooked meat (such as pork, wild boar or deer) in some regions.
• Course: Usually acute and self-limiting, with recovery in a few weeks. People with a weakened immune system can develop chronic infection.
• Incubation period: About 2 to 6 weeks.
• Risk groups: Pregnant women can develop severe disease, with a higher risk of liver failure and death for both mother and baby.
• Vaccine: A vaccine is licensed in China, but it is not widely available elsewhere.

Alcohol-related hepatitis

Long-term heavy alcohol use can inflame and damage the liver. Alcohol-associated hepatitis can be severe and life-threatening, and it often occurs together with fatty liver and cirrhosis.

Autoimmune hepatitis

The immune system mistakenly attacks liver cells. It is more common in women and can occur at any age. Treatment usually involves immune-suppressing medicines.

Drug-induced and toxic hepatitis

Some medicines, herbal products, supplements and chemicals can injure the liver. A well-known example is overdose of acetaminophen (paracetamol), which can cause sudden liver failure. Other drugs, including some antibiotics, anti-tuberculosis medicines and anti-seizure medicines, can also harm the liver in some people. Mushroom poisoning (such as Amanita phalloides) is another toxic cause.

Metabolic dysfunction–associated steatotic liver disease (MASLD)

Fat buildup in the liver, usually linked to obesity, type 2 diabetes and metabolic syndrome, can cause inflammation (steatohepatitis) and progress to scarring. This is now one of the most common causes of chronic liver disease worldwide.

Other causes

• Other viruses, such as cytomegalovirus and Epstein–Barr virus
• Inherited conditions, such as Wilson disease and hemochromatosis
• Blocked blood flow or bile flow, and shock or severe heart failure affecting the liver

Many people with hepatitis, especially chronic hepatitis B and C, have no symptoms at all for years. When symptoms occur, they may include:

• Fatigue and weakness
• Loss of appetite
• Nausea and vomiting
• Mild fever
• Pain or discomfort in the upper right part of the abdomen
• Jaundice: Yellowing of the skin and the whites of the eyes
• Dark urine
• Pale or clay-colored stools
• Joint and muscle aches
• Itchy skin

Signs of advanced liver disease

• Swelling of the abdomen (ascites) or legs
• Easy bruising or bleeding
• Vomiting blood or black stools
• Confusion, drowsiness or personality changes (hepatic encephalopathy)
• Spider-like blood vessels on the skin
• Muscle wasting and weight loss

When to see a doctor

See a doctor if you have jaundice, persistent fatigue, dark urine, pale stools or ongoing abdominal pain. Also get tested if you may have been exposed to hepatitis, even without symptoms. Examples include having shared needles, having had a sexual partner with hepatitis, being born to a mother with hepatitis, or having received blood products or medical care in settings where infection control may have been poor.

Seek urgent medical care for confusion, extreme drowsiness, vomiting blood, severe abdominal pain or swelling, or yellow skin with fever or very high fatigue.

• Medical history and examination: The doctor asks about symptoms, travel, food and water exposure, medicines, alcohol use, family history, injections, tattoos, sexual history and vaccination history. They check for jaundice, liver tenderness and signs of liver disease.
• Liver function tests: Blood tests measure liver enzymes (ALT and AST), bilirubin, albumin and clotting time (INR). Raised enzymes suggest liver inflammation but do not identify the cause.
• Viral hepatitis blood tests:

• Hepatitis A: IgM anti-HAV indicates recent infection. IgG anti-HAV shows past infection or vaccination.
• Hepatitis B: HBsAg shows current infection. Anti-HBs shows immunity. Anti-HBc shows past or present exposure. HBeAg and HBV DNA show how actively the virus is replicating.
• Hepatitis C: Anti-HCV antibody shows exposure. A positive result is confirmed with an HCV RNA test, which shows active infection.
• Hepatitis D: Tested in people who have hepatitis B.
• Hepatitis E: IgM anti-HEV and HEV RNA.
• Tests for other causes: Autoantibodies, iron studies, tests for Wilson disease, and reviews of medicines and alcohol use
• Imaging: Ultrasound, CT or MRI show the size and texture of the liver, scarring, fluid, tumors and bile duct problems.
• Assessing scarring (fibrosis): Elastography (such as FibroScan) and blood-based scores measure liver stiffness without surgery.
• Liver biopsy: A small sample of liver tissue is examined under a microscope. It is used when the diagnosis is unclear or to assess damage more precisely.

Treatment depends on the cause and whether the disease is acute or chronic.

Hepatitis A and E

There is usually no specific antiviral treatment. Care is supportive:

• Rest
• Plenty of fluids and good nutrition
• Avoiding alcohol and medicines that stress the liver
• Hospital care for severe illness, including pregnant women with hepatitis E and anyone with signs of liver failure

Hepatitis B

• Acute hepatitis B: Usually supportive care. Antivirals are used only in severe cases.
• Chronic hepatitis B: Antiviral medicines such as tenofovir or entecavir suppress the virus, reduce liver damage and lower the risk of cirrhosis and cancer. Treatment is often long-term and may be lifelong. Pegylated interferon is used in some patients for a fixed period. The virus is usually controlled rather than fully eliminated.
• Monitoring: Regular blood tests and imaging are needed, including ultrasound to screen for liver cancer in people at higher risk.

Hepatitis C

Direct-acting antivirals (DAAs), such as sofosbuvir-based and glecaprevir/pibrentasvir regimens, are taken by mouth for about 8 to 12 weeks and cure more than 95% of people. A cure is called a sustained virologic response, meaning no virus is detected in the blood months after treatment ends. After a cure, people with advanced scarring still need ongoing liver monitoring. Being cured does not protect against catching hepatitis C again.

Hepatitis D

Treatment is limited. Options include pegylated interferon and, in some countries, a newer medicine called bulevirtide. Treating the underlying hepatitis B is also important.

Autoimmune hepatitis

Treated with corticosteroids and other immune-suppressing medicines, usually for a long time.

Alcohol-related and fatty liver–related hepatitis

• Stopping alcohol completely is the most important treatment for alcohol-related liver disease.
• For MASLD, weight loss, healthy eating, exercise and control of diabetes, blood pressure and cholesterol are central. Some medicines may be used in selected patients.

Drug-induced hepatitis

Stopping the offending medicine, under a doctor’s supervision, is the first step. Acetaminophen overdose requires urgent treatment with the antidote N-acetylcysteine, ideally as early as possible.

Advanced liver disease and transplant

Cirrhosis complications are managed with medicines, procedures and diet changes. When the liver fails, a liver transplant may be needed.

• Cirrhosis
• Liver failure (acute or chronic)
• Portal hypertension, causing swollen veins in the esophagus that can bleed
• Ascites and infection of the abdominal fluid
• Hepatic encephalopathy
• Hepatocellular carcinoma (liver cancer)
• Kidney problems linked to advanced liver disease

• Attend regular check-ups, blood tests and scans as advised.
• Take medicines exactly as prescribed, and do not stop antivirals without asking your doctor, especially for hepatitis B.
• Avoid alcohol if you have liver disease.
• Check with a doctor or pharmacist before taking any over-the-counter medicine, herbal product or supplement. Do not exceed the recommended dose of acetaminophen.
• Get vaccinated against hepatitis A and B if you are not already immune.
• Eat a balanced diet and maintain a healthy weight.
• Protect others. Do not share razors, toothbrushes, nail clippers or needles, and cover cuts. People with hepatitis B or C can safely live and work with others, and can share meals and hug family members.
• Tell your doctor or dentist about your infection, and make sure household and sexual partners are tested and vaccinated if appropriate.
• Seek emotional support. A diagnosis can bring worry and stigma, and counseling and patient groups can help.

Vaccination

• Hepatitis A vaccine: Recommended for children in many countries, travelers to areas where hepatitis A is common, and people at higher risk.
• Hepatitis B vaccine: Recommended for all infants, starting at birth, and for children, adolescents and adults who have not been vaccinated, especially healthcare workers and people at higher risk. A complete series gives long-lasting protection.
• Hepatitis E: A vaccine is available in only a few countries.
• Hepatitis C: No vaccine exists.

Hygiene and safe food and water

• Wash hands thoroughly with soap and water after using the toilet and before preparing or eating food.
• Drink safe, treated water, and avoid uncooked food or ice made from unsafe water when traveling.
• Cook meat, especially pork and game, thoroughly.

Preventing blood-borne spread

• Never share needles, syringes or other drug equipment, and use sterile needles for injections, tattoos and piercings.
• Use condoms during sex, especially with new or multiple partners.
• Use only licensed, properly sterilized medical, dental and cosmetic services.
• Make sure blood and blood products are screened.
• Pregnant women should be tested for hepatitis B. Babies born to mothers with hepatitis B should receive the vaccine, and often hepatitis B immune globulin, within 24 hours of birth.

Protecting the liver in general

• Limit alcohol.
• Maintain a healthy weight and stay active.
• Take medicines and supplements only as directed.

• “Hepatitis spreads by casual contact.” Hepatitis B and C do not spread through hugging, shaking hands, coughing, sneezing or sharing meals. Hepatitis A and E spread through contaminated food and water.
• “If I have no symptoms, I’m not infected.” Chronic hepatitis B and C can be silent for years while damaging the liver.
• “Hepatitis C can’t be cured.” Modern antivirals cure more than 95% of people.
• “Hepatitis B vaccine is only for high-risk people.” It is recommended for all infants and for any unvaccinated person who wants protection.
• “Only people who inject drugs get hepatitis C.” Other exposures, such as unsafe medical procedures and past blood transfusions, can also transmit it.
• “Herbal liver detox products can treat hepatitis.” No herbal or detox product has been shown to cure viral hepatitis, and some can harm the liver.
• “Yellow skin always means hepatitis.” Jaundice can have many causes, including gallstones, blood disorders and cancers, so it always needs medical assessment.

What is the difference between hepatitis A, B and C?

Hepatitis A spreads through contaminated food and water and is always short-term. Hepatitis B and C spread mainly through blood and body fluids and can become chronic. A vaccine prevents A and B, and C can be cured with medicines.

Which type of hepatitis is the most dangerous?

Hepatitis B and C cause the most long-term harm because chronic infection can lead to cirrhosis and liver cancer. Any type can be dangerous in people with existing liver disease, and hepatitis E can be dangerous in pregnancy.

Can hepatitis go away on its own?

Hepatitis A and E usually resolve by themselves. Most healthy adults clear acute hepatitis B. Some people clear hepatitis C without treatment. Chronic infections need medical follow-up.

Is hepatitis B curable?

Treatment can control the virus and prevent liver damage, but it rarely eliminates the virus completely. Many people with chronic hepatitis B live long, healthy lives with proper monitoring and treatment.

Can I get hepatitis more than once?

You can get hepatitis A, B, C, D and E separately, because each is a different virus. Once you recover from A or B, you are usually immune to that virus. After a hepatitis C cure, you can be infected again.

Can I donate blood if I had hepatitis?

Rules vary by country. In general, people with a history of hepatitis B or C cannot donate blood. Ask your local blood service.

Can hepatitis be passed to a baby during pregnancy?

Hepatitis B and C can pass from mother to baby, mostly during birth. Vaccination of the baby, and sometimes antiviral treatment for the mother, greatly reduces the risk for hepatitis B. Pregnant women should be tested.

Does hepatitis affect life expectancy?

With early diagnosis, treatment and monitoring, many people with hepatitis B or C have a normal life expectancy. Without treatment, progression to cirrhosis or liver cancer can shorten life.

How often should people with chronic hepatitis be monitored?

It depends on the type and the stage of liver disease. Many people need blood tests and ultrasound every 6 to 12 months. Your doctor will set the right schedule for you.

• World Health Organization. Hepatitis B fact sheet: https://www.who.int/news-room/fact-sheets/detail/hepatitis-b
• World Health Organization. Hepatitis C fact sheet: https://www.who.int/news-room/fact-sheets/detail/hepatitis-c
• World Health Organization. Hepatitis A fact sheet: https://www.who.int/news-room/fact-sheets/detail/hepatitis-a
• World Health Organization. Hepatitis E fact sheet: https://www.who.int/news-room/fact-sheets/detail/hepatitis-e
• Centers for Disease Control and Prevention. Viral Hepatitis: https://www.cdc.gov/hepatitis/
• National Institute of Diabetes and Digestive and Kidney Diseases. Hepatitis: https://www.niddk.nih.gov/health-information/liver-disease

This article is for general educational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Hepatitis care depends on the type, the stage of liver disease and the individual, so always talk to a qualified healthcare professional about your own symptoms, test results and treatment choices. If you have yellow skin with confusion, vomiting blood, severe abdominal pain or any other medical emergency, contact your local emergency services or seek urgent care immediately.