Hepatitis B is not a particularly common condition in the United States. Data from 2021 estimates that between 880,000 and 1.89 million individuals are living with chronic hepatitis B in the U.S. This infection is much more common in other areas of the world.

These statistics come from the Centers for Disease Control and Prevention (CDC).

Hepatitis B is a viral condition that damages the liver and causes inflammation. This can lead to symptoms such as severe fatigue, fever, and vomiting. The cause of hepatitis B is the hepatitis B virus (HBV), which spreads through contact with bodily fluids.

Acute hepatitis B occurs when the body is able to fight off the infection on its own, while chronic hepatitis B is a long-term infection that most commonly affects people who contracted HBV at a young age.

Read on to learn more about how common hepatitis B is, the chances of contracting it, and treatment.

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Roughly 880,000 to 1.89 million people in the U.S. are living with chronic hepatitis B. This statistic is based on reported cases and an estimated number of unreported cases.

While less than 0.5% of the U.S. population is living with hepatitis B, the infection is much more common in other areas of the world.

According to the Hepatitis B Foundation, hepatitis B is “the most common serious liver infection in the world.” About 300 million people globally are living with chronic hepatitis B. In sub-Saharan Africa and some Asian countries, such as Vietnam and Mongolia, at least 8% of the population has the hepatitis B virus.

Current research suggests that 69% of people living with chronic hepatitis B in the U.S. were born outside the country. Part of the reason for this may be a lower level of awareness or difficulty accessing healthcare.

Of the people who contract the virus as adults, only 5–10% will go on to develop chronic hepatitis B. This likelihood increases to 25–50% for those who acquire the virus between the ages of 1 and 5 years. Infants who contract the hepatitis B virus have a 90% chance of developing a chronic infection.

HBV transmits through contact with bodily fluids that contain the virus, such as semen or blood. The infection can also transmit via a contaminated object that punctures the skin.

Actions that may result in a person contracting hepatitis B include:

  • having sex without a barrier method with someone who has hepatitis B
  • sharing used needles or syringes
  • sharing personal items, such as toothbrushes or razors, with someone who has hepatitis B
  • touching the open wound of a person with hepatitis B
  • being born to someone with hepatitis B

A person’s chances of contracting HBV depend on how closely they interact with people who may be carrying the virus.

One of the main routes of transmission is through sexual contact. A person’s chances of contracting HBV this way are higher if they:

  • have sex with someone who has hepatitis B
  • are a man who has sex with men
  • have sex with multiple partners

Experts recommend that all men who engage in sexual activity with other men receive the hepatitis B vaccination. The risk of transmitting the virus can also be reduced by using barriers, such as condoms, during sex.

Individuals who inject drugs are also at an increased risk of contracting hepatitis B. Sharing needles, syringes, and other equipment used for injecting drugs is one of the top causes of hepatitis B transmission in the U.S.

Other individuals at higher risk of contracting hepatitis B include:

  • healthcare professionals who are exposed to bodily fluids
  • people sharing a household with someone with hepatitis B
  • people who have spent time in countries with a high hepatitis B presence
  • people with a chronic liver disease
  • people with other infections, such as hepatitis C and HIV
  • people who received blood transfusions or organs before the mid-1980s

Chances of transmitting hepatitis B through pregnancy

Hepatitis B can transmit to fetuses during pregnancy. Without medical intervention, around 40% of newborns that are born to a parent who has HBV will go on to develop chronic hepatitis B.

However, this risk goes down significantly if a person receives hepatitis B immunoglobin (HBIG) and the hepatitis B vaccination while they are still pregnant. Doctors can also administer these to infants after birth to further reduce the risk.

In cases of acute hepatitis B, treatment is usually not necessary. A person’s immune system will fight the virus, although this can take several weeks. In some cases, it takes up to 6 months.

For those with chronic hepatitis B, there is no cure. However, not everyone needs treatment. Instead, doctors may monitor the condition and watch for signs that HBV is causing damage, such as liver damage. If it does, they may prescribe antiviral drugs.


The best way to prevent hepatitis B is vaccination. The World Health Organization (WHO) reports that the hepatitis B virus vaccination is 98–100% effective in preventing infection.

Doctors recommend the vaccination for infants, children, and teens in the U.S. Adults who are at an increased risk of contracting hepatitis B should also consider vaccination.

A full course of the vaccination involves three separate injections. Studies suggest that it provides immunity for at least 30 years. Research into the long-term duration of the vaccination is ongoing.

Anyone who thinks they may have been exposed to hepatitis B should contact a doctor immediately. Hepatitis B does not always cause symptoms right away, so a person should seek medical advice even if they feel well.

A doctor can give the hepatitis B vaccine, and potentially HBIG, to prevent infection. This is most effective if a person receives treatment in the first 24 hours after exposure.

If a person has some of the risk factors for hepatitis B, but they have never received testing to see if they carry HBV, they should also speak with a doctor. People at a higher risk of contracting the virus may be able to get the hepatitis B vaccine.

While hepatitis B is less common in the United States, this viral infection affects approximately 300 million people worldwide.

Many adults who contract hepatitis B experience an acute infection that goes away on its own. However, some people develop a chronic infection. This has no cure, but treatment can help reduce symptoms and reduce the impact of the virus on the body.

If a person is concerned they may have become exposed to HBV, they should speak with a doctor right away.