Clinical Overview of Viral Hepatitis

Key points

  • Many people with a viral hepatitis infection do not have symptoms and are unaware of their infection.
  • Chronic hepatitis B and chronic hepatitis C can cause serious health problems, including liver damage, cirrhosis, liver cancer, and even death.
  • Hepatitis A and hepatitis B are vaccine-preventable, and hepatitis C can be cured with treatment.
Doctor meeting with a patient to discuss hepatitis resources available for them

Overview of Viral Hepatitis in the US

Each year, tens of thousands of people acquire a viral hepatitis infection in the United States. It is a serious public health threat that kills thousands of Americans annually and is a leading cause of liver cancer. Hepatitis A and hepatitis B are vaccine-preventable, hepatitis B can be treated, and hepatitis C can be cured.

The US has the opportunity and the responsibility to eliminate viral hepatitis as a public health threat. By working with clinicians and their patients, we can collectively achieve this goal. See below for further information on the cause, incidence, and prevalence of the most common types of viral hepatitis in the US.

Hepatitis A

Hepatitis B

Hepatitis C

  • Hepatitis C is caused by the hepatitis C virus (HCV).
  • There were an estimated 67,400 acute infections in 2022.
  • There were an estimated 2.4 million people - and as many as 4 million people - with HCV infection from 2017–2020.1

Types and strains

Viral hepatitis is most commonly caused by three viruses: hepatitis A, hepatitis B, and hepatitis C.

Hepatitis A

  • Less than 30% of children that are younger than 6 years old have symptoms, which do not typically include jaundice.
  • More than 70% of older children and adults have jaundice.

Hepatitis B

  • Most children younger than 5 years old do not have symptoms.
  • People aged 5 years and older develop symptoms in 30%–50% of cases.
  • Newly infected, immunosuppressed adults generally do not show symptoms.

Hepatitis C

  • Jaundice might occur in 20%–30% of people.
  • Nonspecific symptoms like loss of appetite, fatigue, or abdominal pain might be present in 10%–20% of people.

Hepatitis A

Hepatitis A does not progress to chronic infection.

Hepatitis B

Chronic HBV infection develops in approximately:

  • 90% of infants who acquired HBV infection perinatally or at birth.
  • 30% of children who acquired HBV infection between 1–5 years old.
  • 5% of people who acquired HBV infection as adults.

Hepatitis C

Chronic HCV infection develops in most people.

Hepatitis A

  • Most people with acute disease recover with no lasting liver damage.
  • Death is uncommon but occurs more often among older people and/or those with underlying liver disease.

Hepatitis B

  • Most people with acute disease recover with no lasting liver damage.
  • Acute illness is rarely fatal.
  • 15%–25% of people with chronic infection develop chronic liver disease, including cirrhosis, liver failure, or liver cancer.

Hepatitis C

  • Approximately 5%–25% of people with chronic hepatitis C will develop cirrhosis over 10–20 years.
  • People with hepatitis C and cirrhosis have a 1%–4% annual risk for hepatocellular carcinoma.

Incubation period

Many people with viral hepatitis do not have symptoms and are unaware of their infection. If symptoms occur with an acute infection, they can appear anytime from 2 weeks to 6 months after exposure. Symptoms of chronic viral hepatitis can take decades to develop and are typically the same as those for acute infection.

Hepatitis A has an incubation period of 15–50 days, with an average incubation period of 28 days.

Hepatitis B has an incubation period of 60–150 days, with an average incubation period of 90 days.

Hepatitis C has an incubation period of 14–182 days, with an average incubation period of 14–84 days.

How it spreads

The different strains of viral hepatitis are transmitted through several possible exposures:

Hepatitis A is transmitted via fecal-oral route. This can happen through:

  • Ingestion of contaminated food or water.
  • Close person-to-person contact with a person who has HAV infection.
  • Sexual contact with a person who has HAV infection.

Bloodborne transmission of HAV is uncommon.

Hepatitis B is transmitted via percutaneous, mucosal, or nonintact skin exposure to infectious blood or other body fluids. HBV is concentrated most highly in blood, and percutaneous exposure is an efficient mode of transmission.

HBV is transmitted primarily through:

  • Childbirth.
  • Sexual contact.
  • Sharing contaminated needles, syringes, or other equipment used to prepare or inject drugs.

Less common transmission routes for HBV include:

  • Needle-sticks or other sharp instrument injuries.
  • Organ transplantation and dialysis.
  • Interpersonal contact through sharing items such as razors or toothbrushes, or contact with open sores of a person who has HBV infection.

Hepatitis C is transmitted via direct percutaneous exposure to infectious blood. Mucous membrane exposures to blood can also result in transmission, although this route is less efficient.

HCV is transmitted primarily through:

  • Sharing contaminated needles, syringes, or other equipment used to prepare or inject drugs.

Less common transmission routes for HCV include:

  • Childbirth.
  • Sexual contact.
  • Tattooing in unregulated facilities.
  • Needles or other sharp instrument injuries.

Clinical features

Symptoms of all types of viral hepatitis are similar and can include one or more of the following:

  • Abdominal pain, nausea, and/or vomiting
  • Dark urine or clay-colored stools
  • Diarrhea (HAV only)
  • Fatigue
  • Fever
  • Jaundice
  • Joint pain
  • Loss of appetite

Learn more about signs and symptoms of HAV infection, HBV infection, and HCV infection.

Prevention

Hepatitis A and hepatitis B are vaccine-preventable. If you suspect a person has been exposed, testing and treatment can prevent complications and interrupt further transmission.

Hepatitis A and hepatitis B vaccines are safe and effective, and they are the best way to prevent HAV and HBV infections. Recommendations for hepatitis A and hepatitis B vaccination include:

Hepatitis A

Children including:

  • All children aged 12–23 months old.
  • Unvaccinated children and adolescents aged 2–18 years old.

People at increased risk for HAV infection:

  • International travelers.
  • Men who have sex with men.
  • People who use injection or non-injection drugs.
  • People with occupational risk for exposure.
  • People who anticipate close personal contact with an international adoptee.
  • People experiencing homelessness.
  • People in settings that provide services to adults of which a high proportion have risk factors for HAV infection.

People at increased risk for severe disease from HAV infection:

  • People with chronic liver disease.
  • People with human immunodeficiency virus (HIV) infection.

Other people recommended for vaccination:

  • Pregnant people at risk for HAV infection or severe outcome from HAV infection.
  • Anyone who requests vaccination.

Vaccination during outbreaks:

  • Unvaccinated people in outbreak settings who are at risk for HAV infection or at risk for severe disease from HAV.

Hepatitis B

  • All infants, and unvaccinated children and adolescents aged 18 years and younger.
  • All adults aged 19–59 years.
  • Adults aged 60 years and older who request vaccination.
  • Adults aged 60 years and older with known risk factors for hepatitis B.

Clinical information for hepatitis A and hepatitis B vaccination‎

Learn more about recommendations and options for hepatitis A vaccination and hepatitis B vaccination.

Hepatitis C

There is currently no vaccine available for hepatitis C. Learn more on how to prevent and control the spread of HCV.

Testing, screening, and diagnosis

Testing is the only way to diagnose a viral hepatitis infection.

  • For hepatitis A, test for immunoglobulin M (IgM) anti-HAV.
  • For hepatitis B, test for hepatitis B surface antigen (HBsAg) plus IgM antibody to hepatitis B core antigen (anti-HBc).
  • For hepatitis C, there is no serologic marker for acute infection.

Hepatitis A

Hepatitis A does not progress to chronic infection. Learn more about hepatitis A testing guidelines.

Hepatitis B

When screening for the first time, tests for chronic infection should include the triple panel test for three HBV seromarkers:

  • Hepatitis B surface antigen (HBsAg).
  • Antibody to hepatitis B surface antigen (anti-HBs).
  • Total antibody to hepatitis B core antigen (total anti-HBc).

For periodic risk-based testing, consider using the triple panel test, or anti-HBc followed (if positive) by HBsAg and anti-HBs.

Universal screening recommendations:

  • Screen all adults aged 18 years and older at least once in their lifetime.
  • All pregnant people should be tested for HBsAg during every pregnancy, preferably in the first trimester.
  • Infants born to HBsAg-positive people should receive postvaccination serologic testing for HBsAg and anti-HBs.
  • Test anyone who requests HBV testing regardless of risk because many people may be reluctant to disclose stigmatizing behaviors.

Risk-based testing is recommended for people with a history of risk, regardless of age, if they were susceptible during the period of increased risk, and periodic testing if there is ongoing risk while susceptible, including:

  • People born in regions with intermediate and high HBV endemicity (HBsAg prevalence of 2% or higher).
  • People born in U.S. not vaccinated as infants whose parents were born in regions with high HBV endemicity (HBsAg prevalence of 2% or higher).
  • Household or sexual contacts of people who are HBsAg-positive.
  • Men who have sex with men.
  • People who inject or have injected drugs.
  • Patients with alanine aminotransferase (ALT) levels (19 IU/L or higher for women, and 30 IU/L or higher for men) of unknown etiology.
  • People with end-stage renal disease, including hemodialysis patients.
  • People receiving immunosuppressive therapy.
  • People with HIV.
  • Donors of blood, plasma, organs, tissues, or semen.
  • People with a current or a history of sexually transmitted infection.
  • People who are currently or were formerly incarcerated.
  • People with HCV infection.

Learn more about hepatitis B testing guidelines.

Hepatitis C

There is no serologic marker for acute HCV infection. Testing for chronic hepatitis C should include:

  • Assay for HCV antibody.
  • Qualitative and quantitative nucleic acid tests (NAT) to detect and quantify presence of virus (HCV RNA).

Clinicians should initiate hepatitis C testing with an HCV antibody test with reflex to NAT for HCV RNA if the antibody test is positive/reactive. See the complete testing sequence.

Requiring multiple patient visits to collect samples should be discontinued.

Universal screening is recommended for:

  • All adults aged 18 years and older at least once in their lifetime.
  • All pregnant people during each pregnancy.
  • Anyone who requests HCV testing regardless of risk because many people may be reluctant to disclose stigmatizing behaviors.

One-time testing regardless of age or setting prevalence is recommended for:

  • People with HIV.
  • People who have ever injected drugs and shared needles, syringes, and/or other equipment, including those who injected once or a few times many years ago.
  • People with persistently abnormal ALT levels.
  • People who received clotting factor concentrates produced before 1987.
  • People who received an organ transplant or a transfusion of blood or blood components before July 1992.
  • People who were notified that they received blood from a donor who later tested positive for HCV infection.
  • Health care, emergency medical, and public safety personnel after needle sticks, sharps, or mucosal exposures to HCV-positive blood.
  • Children aged 2–6 months born to people with known HCV infection in pregnancy, as well as:
    • Untested siblings born to same parent.
    • Children born to persons with unknown HCV status during pregnancy if birth parent cannot be tested.

Routine periodic testing is recommended for people with ongoing risk factors while risk factors exist, including:

  • People with select medical conditions, such as those who have ever received maintenance hemodialysis.
  • People who currently inject drugs and/or share needles, syringes, or other drug preparation equipment.

Learn more about hepatitis C testing guidelines.

Treatment and recovery

Treatment for viral hepatitis varies by the type and severity of each infection.

HAV infection is best addressed through supportive care like rest, fluids, a well-balanced diet, and plenty of fluids to relieve symptoms.

Acute HBV infection is best addressed through supportive care like rest, a well-balanced diet, and plenty of fluids to relieve symptoms. Chronic HBV infection should be monitored for signs of liver disease progression and treated with antiviral drugs.

The Infectious Diseases Society of America (IDSA) and the American Association for the Study of Liver Diseases (AASLD) recommend treatment of acute and chronic HCV infection without a waiting period. More than 95% of people with HCV infection can be cured regardless of HCV genotype with 8–12 weeks of oral therapy.

Content Source:
Division of Viral Hepatitis
  1. Hall EW, Bradley H, Barker LK, Lewis K, Shealey J, Valverde E, Sullivan P, Gupta N, Hofmeister MG. Estimating hepatitis C prevalence in the United States, 2017-2020. Hepatology. 2024 May 13.