Overview of Viral Hepatitis for Health Care Professionals

Tens of thousands of people are newly infected with viral hepatitis every year 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 and hepatitis C can be cured.
The United States has the opportunity and the responsibility to eliminate viral hepatitis as a public health threat. Working with providers and their patients we can collectively achieve this goal.
What causes it?
Hepatitis A is caused by the hepatitis A virus (HAV)
Hepatitis B is caused by the hepatitis B virus (HBV)
Hepatitis C is caused by the hepatitis C virus (HCV)
U.S. Statistics
Routes of Transmission
Hepatitis A
Fecal-oral route
HAV is transmitted through:
- Close person-to-person contact with an infected person
- Sexual contact with an infected person
- Ingestion of contaminated food or water
Although viremia occurs early in infection, bloodborne transmission of HAV is uncommon
Hepatitis B
Percutaneous, mucosal, or nonintact skin exposure to infectious blood, semen, and/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:
- Birth to an infected pregnant person
- Sexual contact with an infected person
- Sharing contaminated needles, syringes, or other equipment used to inject drugs
Less commonly transmitted through:
- 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 an infected person
Hepatitis C
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 inject drugs
Less commonly transmitted through:
- Birth to an infected pregnant person
- Sexual contact with an infected person
- Unregulated tattooing
- Needle-sticks or other sharp instrument injuries
Incubation Period
Hepatitis A
15–50 days
(average: 28 days)
Hepatitis B
60–150 days
(average: 90 days)
Hepatitis C
14–182 days
(average range: 14–84 days)
Symptoms of all types of viral hepatitis are similar and can include one or more of the following:
- Jaundice
- Fever
- Fatigue
- Loss of appetite
- Nausea
- Vomiting
- Abdominal pain
- Joint pain
- Dark Urine
- Clay-colored stool
- Diarrhea (HAV only)
Many people with hepatitis do not have symptoms and do not know they are infected. 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.
Likelihood of Symptomatic Acute Infection
Hepatitis A
- Less than 30% of children that are less 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 less than 5 years old do not have symptoms
- 30%–50% of people 5 years and older develop symptoms
- Newly infected immunosuppressed adults generally do not have symptoms
Hepatitis C
- Jaundice might occur in 20%–30% of people
- Nonspecific symptoms like anorexia, malaise, or abdominal pain might be present in 10%–20% of people
Potential for Chronic Infection after Acute Infection
Hepatitis A
None
Hepatitis B
Chronic infection develops in approximately:
- 90% of infants after acute infection at birth
- 30% of children newly infected at ages 1–5 years
- 5% of people newly infected as adults
Hepatitis C
Chronic infection develops in most newly infected people
Severity
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
Serologic Tests for Acute Infection
Hepatitis A
- IgM anti-HAV
Hepatitis B
- HBsAg, plus
- IgM anti-HBc
Hepatitis C
- No serologic marker for acute infection
Serologic Tests for Chronic Infection
Hepatitis A
- Not applicable—no chronic infection
Hepatitis B
When screening for the first time, tests for chronic infection should include three HBV seromarkers:
- HBsAg
- anti-HBs
- 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
Hepatitis C
- Assay for anti-HCV
- Qualitative and quantitative nucleic acid tests (NAT) to detect and quantify presence of virus (HCV RNA)
Testing Recommendations for Chronic Infection
Hepatitis A
- Not applicable—no chronic infection
Note: testing for past acute infection is generally not recommended
Hepatitis B
- All adults aged 18 years and older at least once in their lifetime
- All pregnant people should be tested for HBsAg during an early prenatal visit in each pregnancy
- Infants born to HBsAg-positive people (HBsAg and anti-HBs are only recommended).
- Anyone who requests testing regardless of risk because many may be reluctant to disclose stigmatizing behaviors
Testing 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 ≥2%)
- People born in U.S. not vaccinated as infants whose parents were born in regions with high HBV
- 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 levels (≥19 IU/L for women and ≥30 IU/L 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 current or history of sexually transmitted infection
- People who are currently or formerly incarcerated
- People with HCV infection
Hepatitis C
- Universal screening for:
- All adults aged 18 years and older at least once in their lifetime
- All pregnant people during every pregnancy, except in settings where the prevalence of HCV infection is less than 0.1%.
- One-time testing regardless of age or setting prevalence:
- People with HIV
- People who ever injected drugs and shared needles, syringes, 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 born to people with HCV infection in pregnancy
- Routine periodic testing for people with ongoing risk factors, while risk factors exist including:
- People with selected medical conditions such as those who ever received maintenance hemodialysis
- People who currently inject drugs and/ share needles, syringes, or other drug preparation equipment
- Any person who requests hepatitis C testing
Hepatitis A
- No medication available
- Best addressed through supportive treatment
Hepatitis B
- Acute: no medication available; best addressed through supportive treatment
- Chronic: regular monitoring for signs of liver disease progression; antiviral drugs are available
Hepatitis C
- AASLD/IDSA recommends treatment of acute HCV and chronic without a waiting period. More than 95% of people with hepatitis C can be cured regardless of HCV genotype with 8–12 weeks of oral therapy
Recommendations
Hepatitis A
- All children aged 12–23 months
- Unvaccinated children and adolescents aged 2–18 years
People at increased risk for HAV infection
- International travelers
- Men who have sex with men
- People who use injection or noninjection drugs
- People with occupational risk for exposure
- People who anticipate close personal contact with an international adoptee
- People experiencing homelessness
People at increased risk for severe disease from HAV infection
- People with chronic liver disease
- People with HIV infection
Other people recommended for vaccination
- Pregnant women 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
Implementation strategies for settings providing services to adults
- People in settings that provide services to adults in which a high proportion of those people have risk factors for HAV infection
Hepatitis B
- All infants, and unvaccinated children and adolescents who are 18 years old and younger
- All adults aged 19 through 59 years
- Adults aged 60 years and older who request vaccination
- Adults aged 60 years and older with known risk factors for hepatitis B
Hepatitis C
- There is no hepatitis C vaccine
* Based on a representative sample of the civilian, noninstitutionalized U.S. population.