Viral hepatitis is an infection of the liver caused by one of several viruses, each spread differently and causing different patterns of illness

Viral hepatitis means the liver is inflamed because a virus has infected it. Unlike bacterial infections, which antibiotics can treat, viral hepatitis requires your immune system to fight the virus itself—or in some cases, antiviral drugs that slow its spread. The five main types are hepatitis A, B, C, D, and E, named simply because they were discovered in that order. Each virus behaves differently: some clear on their own within weeks, others hide in the liver for life, and one requires a second virus to exist at all.

The liver filters blood, makes proteins, stores energy, and breaks down toxins. When a virus inflames it, these jobs slow down. You might feel nothing at all, or you might develop jaundice (yellowing of skin and eyes), dark urine, pale stools, fatigue, and belly pain. Some people recover completely. Others develop chronic infection—meaning the virus stays in the body for more than six months—which can lead to cirrhosis (scarring) and liver cancer over years or decades.

Key Takeaways

  • Hepatitis A spreads through contaminated food or water and clears on its own; hepatitis B and C spread through blood or body fluids and can become chronic.
  • Hepatitis D only occurs in people already infected with hepatitis B and makes that infection worse.
  • Hepatitis E spreads through contaminated water and usually clears on its own, though it is dangerous in pregnant people.
  • Many people with chronic hepatitis B or C have no symptoms for years, so blood tests are the only way to know if you are infected.
  • Vaccines exist for hepatitis A and B; no vaccine exists yet for C, D, or E.

How the five types differ in spread and outcome

Hepatitis A spreads through contaminated food or water, usually in places where sanitation is poor. It causes acute illness—meaning it comes on suddenly and lasts weeks to months—but does not become chronic. Once you recover, you are immune for life. Hepatitis A is the mildest form and rarely causes permanent liver damage, though it can be severe in older adults or people with existing liver disease.

Hepatitis B spreads through blood, semen, vaginal fluid, and other body fluids. Transmission happens through unprotected sex, sharing needles, or (rarely in developed countries) from mother to newborn during birth. About 90 percent of infected adults clear the virus within six months. The other 10 percent develop chronic hepatitis B, meaning the virus stays in their blood and liver indefinitely. Chronic infection can lead to cirrhosis and liver cancer.

Hepatitis C spreads through blood-to-blood contact, most commonly from sharing needles or, historically, through blood transfusions before screening began. About 15 to 25 percent of people clear the virus on their own. The rest develop chronic infection. For decades, chronic hepatitis C had no cure, but direct-acting antiviral drugs developed in the 2010s now cure most people who take them—usually within 8 to 12 weeks of treatment.

Hepatitis D (also called delta hepatitis) is unusual: it can only infect people who already have hepatitis B. It spreads the same way as hepatitis B and makes the infection worse, increasing the risk of cirrhosis and liver cancer. People without hepatitis B cannot get hepatitis D.

Hepatitis E spreads through contaminated water, similar to hepatitis A. It usually clears on its own within weeks or months. However, it poses serious risk to pregnant people, who can develop severe liver failure and are at higher risk of losing the pregnancy.

Symptoms and when they appear

Symptoms of viral hepatitis typically appear 2 to 12 weeks after infection, depending on the type and the individual. Early signs include fatigue, joint pain, fever, nausea, and loss of appetite. As the infection progresses, jaundice often develops—yellowing of the skin and whites of the eyes—along with dark urine and pale or clay-colored stools. Belly pain and itching are common.

Many people with acute hepatitis have mild symptoms or none at all, especially children. This is why blood tests matter: you can be infected and contagious without feeling sick. In chronic hepatitis B and C, most people have no symptoms for years or even decades, even as the virus slowly damages the liver. By the time symptoms appear—fatigue, swelling in the legs, confusion, or vomiting blood—significant scarring may already have occurred.

How doctors test for viral hepatitis

Blood tests are the only way to know if you have viral hepatitis. Different tests detect different things: some look for antibodies (proteins your immune system makes against the virus), others look for the virus itself or enzymes the liver releases when damaged. Your doctor will order specific tests based on your risk factors and symptoms.

For hepatitis A, a positive antibody test means you either have acute infection or are immune from past infection. For hepatitis B and C, tests can show whether you have current infection or past infection. If you test positive for hepatitis B or C, additional tests measure how much virus is in your blood (viral load) and whether the liver is already scarred (fibrosis staging).

If you have risk factors—such as a history of needle sharing, unprotected sex with multiple partners, or a family member with hepatitis—your doctor may recommend testing even if you have no symptoms. People born in countries where hepatitis B is common are also often screened.

Treatment options vary by type and stage

Hepatitis A has no specific treatment. Care focuses on rest, fluids, and managing symptoms while your immune system clears the virus. Most people recover fully without medication.

Hepatitis B treatment depends on whether the infection is acute or chronic and how much liver damage has occurred. Acute hepatitis B usually requires only supportive care. Chronic hepatitis B may be treated with antiviral drugs (such as tenofovir or entecavir) that slow the virus and reduce the risk of cirrhosis and cancer, though they do not cure the infection. Treatment decisions depend on viral load, liver damage, and other health factors.

Hepatitis C is now often curable. Direct-acting antivirals (DAAs)—drugs like sofosbuvir, ledipasvir, and others—target specific parts of the virus and cure the infection in 95 percent or more of people who complete treatment. Treatment typically lasts 8 to 12 weeks. Even people with advanced cirrhosis can be cured, though they need monitoring afterward for liver cancer risk.

Hepatitis D is treated with interferon, an immune-boosting drug, though results are modest. Hepatitis E usually requires only supportive care, as most people recover on their own.

Prevention through vaccination and behavior

Vaccines exist for hepatitis A and B. The hepatitis A vaccine is given as two shots, several months apart, and provides lifelong immunity. The hepatitis B vaccine is also highly effective and is now given to all infants in most developed countries; adults at risk can also be vaccinated. Some vaccines combine both.

No vaccine exists yet for hepatitis C, D, or E. Prevention relies on avoiding exposure: not sharing needles or personal items that might have blood on them, practicing safer sex, and (for hepatitis A and E) ensuring access to clean water and sanitation. Healthcare workers and others at occupational risk of blood exposure follow strict protocols to prevent transmission.

If you are exposed to hepatitis A—for example, through contaminated food—post-exposure prophylaxis (a shot of immunoglobulin or a dose of hepatitis A vaccine) given within two weeks can prevent infection or reduce severity.

Long-term complications and monitoring

Acute viral hepatitis usually resolves without lasting damage. However, chronic hepatitis B and C can lead to cirrhosis over 10 to 40 years, depending on the individual and whether treatment is received. Cirrhosis means the liver is so scarred it cannot function properly, leading to fluid buildup, bleeding, confusion, and kidney failure.

People with chronic hepatitis B or C also have increased risk of hepatocellular carcinoma (liver cancer), even if cirrhosis has not yet developed. For this reason, people with chronic infection are monitored with blood tests and ultrasound imaging at regular intervals. If cirrhosis develops, monitoring becomes more frequent.

Treatment with antivirals (for hepatitis B) or DAAs (for hepatitis C) reduces but does not eliminate the risk of cirrhosis and cancer. People who are cured of hepatitis C still need periodic screening for cancer. People with cirrhosis from any cause may eventually need a liver transplant.

Frequently Asked Questions

Can you get viral hepatitis from sharing a glass or hugging someone?

No. Hepatitis A and E spread through contaminated food or water, not saliva. Hepatitis B, C, and D require blood-to-blood contact or exposure to other body fluids and cannot be spread by casual contact, sharing utensils, or hugging. You cannot get any form of viral hepatitis from breathing the same air as an infected person.

If I had hepatitis A as a child, can I get it again?

No. Once you recover from hepatitis A, your immune system remembers the virus and protects you for life. You are immune even if you were never vaccinated. Immunity to hepatitis B and C does not develop the same way; people can be reinfected with these types.

How long does it take to know if treatment for hepatitis C worked?

Blood tests for hepatitis C viral load are done at the end of treatment and again 12 weeks later. If the virus is undetectable at both timepoints, the infection is considered cured. Most people know within a few months whether treatment was successful.

Can someone with chronic hepatitis B or C donate blood or organs?

No. Blood banks screen all donations for hepatitis B and C to protect recipients. People with chronic hepatitis B or C are not permitted to donate blood. Organ donation from someone with chronic hepatitis is generally not possible, though in rare cases organs from hepatitis C-positive donors may be transplanted into hepatitis C-positive recipients.

What should I do if I think I was exposed to viral hepatitis?

Contact your doctor or a local health department as soon as possible. If exposure was recent (within two weeks for hepatitis A), post-exposure prophylaxis may prevent infection. For other types, blood tests can determine whether infection has occurred. Your doctor can also advise on whether contacts need to be notified or tested.