Hepatitis B is an infection of the liver that's caused by the hepatitis B virus (HBV). Some people will develop a short-term (acute) infection, which lasts for less than six months, before their bodies fight off the virus. If someone isn't able to fight off the hepatitis B virus, it will cause a long-lasting (chronic) infection, which lasts for six months or longer. Some people with hepatitis B will develop a lifelong infection, according to the Centers for Disease Control and Prevention (CDC).
Hepatitis B is one of five main viral types of hepatitis. The others are hepatitis A, C, D, and E, notes the CDC.
Getting vaccinated can protect you against HBV.
Causes and Risk Factors of Hepatitis B
Hepatitis B is spread when the blood, semen, or other bodily fluid of an infected person enters the body of someone who doesn't have the virus.In the United States, the infection is mainly spread through blood, including during injection drug use and through sex, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
Here are the ways hepatitis B can be spread:
- Through sex with a partner who has the virus
- By sharing needles, syringes, or other drug equipment with someone who has the virus
- During birth, when an infected mother passes the virus to her baby
- By sharing toothbrushes, razors, nail clippers, or other items with an infected person
- Through accidental needle stick injuries that occur from an infected person
- Making direct contact with an infected person's blood or open sores
- Getting a tattoo or piercing from a contaminated needle
Hepatitis B is not spread by hugging, kissing, breastfeeding, sharing eating utensils, shaking hands, or being coughed or sneezed on.
Some people are more at risk for infection than others. The CDC recommends hepatitis B testing for:
- People who were born in countries with high rates of hepatitis B
- People who were born in the United States, but weren't vaccinated as infants, to parents who were from countries with high rates of hepatitis B
- Men who have sex with men
- People who work in a job where they're exposed to blood (such as healthcare workers)
- People who inject drugs
- People who have HIV
- People who live with people who have hepatitis B
- People who are sexually active with someone who has hepatitis B
- Pregnant women
- Infants who are born to mothers with hepatitis B
- People with certain health conditions, such as hepatitis C or end-stage renal disease
How Is Hepatitis B Diagnosed?
Hepatitis B can be diagnosed with a blood test. If you do have the infection, further blood tests can determine whether it is acute or chronic, and whether you're likely to experience liver damage and need treatment.
Other blood tests can determine whether you're immune to the virus, either because you received a hepatitis B vaccine in the past or were previously infected with the virus and fought it off. Once your body fights off hepatitis B, you can't be reinfected with the virus.
If you suspect that you have hepatitis B or are showing symptoms of the infection, talk to your doctor about being tested.
Your doctor may want to screen you for hepatitis B if you have risk factors for the virus — for example, if you're pregnant or HIV-positive — even if you aren't showing symptoms.
Prognosis of Hepatitis B
While there is a vaccine that can prevent hepatitis B, there is no cure. But treatments for chronic hepatitis B can often help prevent the virus from causing liver damage.
The risk that an acute hepatitis B infection will become chronic (and therefore, cause serious complications) decreases as a person gets older. About 90 percent of infants who get hepatitis B will develop a chronic infection, according to the CDC; the virus will become chronic in about 25 to 50 percent of children ages 1 to 5. Of the people who get hepatitis B as a child, about 25 percent may die from cirrhosis or liver cancer.
About 95 percent of adults will completely recover from hepatitis B and won't develop a long-lasting infection, according to the CDC. Approximately 15 percent of people who get hepatitis B after childhood may die of cirrhosis or liver cancer.
Duration of Hepatitis B
Hepatitis B can be an acute or chronic infection. People who have acute hepatitis B — meaning, it lasts less than six months — will clear the infection from their body and likely make a full recovery.This is the case for about 95 percent of people who catch the virus as an adult.
A chronic hepatitis B infection lasts for longer than six months, and possibly a lifetime. About 90 percent of infants who get hepatitis B will develop a chronic infection.The symptoms of hepatitis B may not appear until a person's liver disease becomes severe, which can take years (if not decades) to occur.
Complications of Hepatitis B
Acute hepatitis B usually doesn't cause serious complications. However, in rare instances, people can experience liver failure; their liver stops working and they may need a liver transplant.
Chronic hepatitis B can lead to serious complications, such as cirrhosis, a condition in which scar tissue accumulates on the liver, preventing the organ from working properly and eventually causing liver failure. The infection can also lead to liver cancer as well as kidney disease or inflammation in the blood vessels.
Asian Americans and Hepatitis B
Asian Americans have an increased risk for acquiring chronic hepatitis B. According to Stanford University School of Medicine, 1 in 12 Asian Americans in the United States have chronic hepatitis B, compared with about 1 in 1000 white Americans, which is one of the largest racial health disparities in the country.
The Office of Minority Health, within the U.S. Department of Health and Human Services, notes that approximately half of the people in the United States with chronic hepatitis B are Asian or Pacific Islanders. And that Asian Americans were almost 8 times more likely to die from hepatitis B compared with white Americans.
Resources We Love
Centers for Disease Control and Prevention (CDC)
The CDC provides information for both medical providers and the public about hepatitis B, as well as statistics on national trends in infection rates.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
A part of the National Institutes of Health, the NIDDK conducts research about liver disease (among other conditions) and keeps the public informed about hepatitis B.
Hepatitis B Foundation
This nonprofit advocacy group works to improve quality of life for people with Hepatitis B. On their site, you'll find news on the latest research, links to online support groups, and more.
Additional reporting by Joseph Bennington-Castro.
Editorial Sources and Fact-Checking
- Hepatitis B Questions and Answers for the Public. Centers for Disease Control and Prevention. July 28, 2020.
- What Is Viral Hepatitis? Centers for Disease Control and Prevention. July 28, 2020.
- Hepatitis B: Symptoms and Causes. Mayo Clinic. September 4, 2020.
- Hepatitis B. National Institute of Diabetes and Digestive and Kidney Diseases. June 2020.
- Hepatitis B Questions and Answers for Health Professionals. Centers for Disease Control and Prevention. July 28, 2020.
- Hepatitis B: Diagnosis and Treatment. Mayo Clinic. September 4, 2020.
- Viral Hepatitis Surveillance Report 2018 — Hepatitis B. Centers for Disease Control and Prevention. July 27, 2020.
- What Is Hepatitis B? Stanford Medicine Liver Center.
- Hepatitis and Asian Americans. The U.S. Department of Health and Human Services Office of Minority Health. December 31, 2020.
- Peginterferon Alfa-2a Infection. MedlinePlus. June 15, 2016.
- Hepatitis D. National Institute of Diabetes and Digestive and Kidney Diseases. May 2017.
- What Is Viral Hepatitis? National Institute of Diabetes and Digestive and Kidney Diseases. May 2017.
