Our Vaccine Update feature article “Fast Facts” series continues this month with a focus on hepatitis B. While most families embrace the birth dose of hepatitis B vaccine to give their infants necessary protection, pediatric providers are reporting an increase in families delaying or refusing the birth dose of hepatitis B vaccine. Additionally, comments at the June meeting of the Advisory Committee on Immunization Practices (ACIP) referenced that the current hepatitis B schedule, including the birth dose, will be reviewed — despite strong data to support its safety and effectiveness. As such, we thought this refresher could help draw attention to this virus, the disease it causes, how it's transmitted, why vaccination for hepatitis B continues to be critical, and why the birth dose matters.
Prior to introduction of a hepatitis B vaccine, about 200,000 to 300,000 new hepatitis B infections occurred each year. The introduction of vaccine has led to a significant reduction in cases. Now, about 22,000 people in the United States are diagnosed with new infections each year. About 2,000 of these people will die from their infection.
Since the first recommendations were published in 1982, they have evolved to include a universal infant recommendation as well as catch-up recommendations. The July 2025 Parents PACK feature article, “9,000 Reasons for Routine Childhood Hepatitis B Vaccination,” reviews this evolution in detail and can serve as an excellent resource when talking with families. Importantly, the evolution of recommendations to include a birth dose of vaccine has been pivotal in controlling hepatitis B in the U.S. The birth dose recommendation is not unique to the U.S. The World Health Organization (WHO) recommends a birth dose, and many countries around the world have successfully implemented hepatitis B vaccine birth dose programs. As such, changes to this approach in the U.S. will set us back and undoubtedly allow our progress against this virus to slip.
Recognizing hepatitis B
Hepatitis B virus replicates in the liver to cause acute or chronic infections. When someone is first infected with the virus, it is described as “acute.” If the person’s immune system cannot clear the virus within six months, they are considered to have a “chronic” infection. Some people, particularly young children, will not have initial symptoms, while others will experience severe illness. When symptoms do occur, they can include fatigue, jaundice, abdominal pain, and elevated liver enzymes. Infections that become chronic lead to long-term liver damage, cirrhosis (a condition in which healthy liver tissue is replaced by scar tissue), and liver cancer. While not every chronic hepatitis B infection leads to liver cancer, the risk is real. Both chronic infection and liver cancer are more likely among those infected at birth or in early childhood compared to those infected later in life.
Some groups are at higher risk of infection, including:
- Those born in regions with intermediate or high hepatitis B prevalence, such as Asia, Africa, and the Pacific Islands
- People who use injection drugs
- Men who have sex with men
- People with HIV
- Household or sexual contacts of individuals with hepatitis B
- People taking immunosuppressive therapy or undergoing dialysis
- People with diabetes
Infants born to mothers with hepatitis B are at risk of acquiring hepatitis B during delivery or in the months after birth due to close contact and the potential for exposure to a mother’s blood, such as during breastfeeding when the mother has cracked skin or nipples. Because of this high-risk period, prenatal screening is embedded in obstetric care across the U.S. to be able to counsel the pregnant person and provide prompt medical care to the infant at birth.
While it is important to know who might be at higher risk of infection, it’s important to remember that anyone can get hepatitis B. This is why the vaccine recommendations focused only on high-risk groups did not stop the spread of infection. As such, patients with relevant symptoms should be evaluated for hepatitis B.
Making a hepatitis B diagnosis
Hepatitis B is diagnosed through blood tests that detect viral markers. The key tests include:
- HBsAg (hepatitis B surface antigen): Indicates an active infection, either acute or chronic.
- Anti-HBs (hepatitis B surface antibody): Indicates recovery and immunity from hepatitis B or successful vaccination.
- Anti-HBc (hepatitis B core antibody): Indicates past or current hepatitis B infection; this antibody is not present after vaccination alone.
- IgM anti-HBc: Indicates a recent infection.
- HBV DNA (viral load): Measures how much virus is in the blood. This test is used to monitor chronic hepatitis B infection and response to treatment.
While testing may be done when someone has symptoms, infections may be silent, so screening is a critical component of detecting and diagnosing hepatitis B. Current screening recommendations include:
- Universal screening: All adults aged 18 years and older should be screened for hepatitis B at least once in their lifetime, regardless of risk factors.
- Pregnant individuals: All pregnant women should be screened during each pregnancy, ideally at the first prenatal visit, regardless of vaccination history or prior test results. Many clinicians also opt to screen again closer to delivery.
- High-risk groups: People at higher risk, as described above, should be screened periodically.
- Anyone who requests screening: Because patients are often reluctant to disclose all risk factors, those who request screening should be evaluated.
Screening usually involves using a combination of the HBsAg, anti-HBs, and total anti-HBc tests, as this triple combination can clarify infection status, immunity and susceptibility.
Finally, testing to confirm immunity from vaccination can be challenging to interpret. When vaccinated individuals test positive for hepatitis B surface antibody, this confirms that they are protected from infection. However, circulating antibodies decrease over time and, therefore, may not be measurable. Even with a negative test, patients are most often still protected long term through the presence of memory B and T cells. When confidence in protection is critical, such as for healthcare workers, the recommendation is to revaccinate and test, as discussed in our prior Vaccine Update article, “Communicating with Patients about Hepatitis B Surface Antibodies.”
Treatment and management of hepatitis B
Treatment for hepatitis B depends on whether the infection is acute or chronic, as well as pregnancy status.
- Acute hepatitis B: Most people with acute hepatitis B do not require antiviral treatment. Instead, supportive care (e.g., hydration, rest, and monitoring of liver function) is usually sufficient as most healthy adults will clear the virus on their own. However, close follow-up is essential to make sure they have recovered fully and to monitor for development of chronic infection.
- Chronic hepatitis B: Chronic infection may require long-term antiviral therapy to suppress viral replication and reduce the risk of liver damage, cirrhosis and liver cancer. Typically, an individual should be referred to a clinician experienced in prescribing oral antivirals, such as an infectious disease specialist or gastroenterologist, to discuss the risks and benefits of the medications and when it is appropriate to start treatment. The specialist can also manage monitoring needed during treatment, such as regular liver function tests, HBV DNA levels, and regular screening for hepatocellular carcinoma.
- Pregnant women with hepatitis B: When a woman has high hepatitis B viral loads, her infant may still be at risk for developing infection even with vaccination and treatment at birth. For this reason, some pregnant women are recommended to receive an oral antiviral during the third trimester to decrease the viral load prior to delivery. Regardless of whether a mother receives antiviral treatment during pregnancy, infants should promptly receive vaccine and hepatitis B immune globulin (HBIG) within 12 hours of birth.
Long-term impact
Currently, in the U.S., more than 2 million people are estimated to live with chronic hepatitis B, but 80% of these individuals are not aware of their chronic hepatitis B status.
Among people with chronic hepatitis B infection, a significant proportion develop serious liver complications over time:
- The risk of cirrhosis over a lifetime is estimated at 20% to 30%, though it varies depending on age at infection, viral load, presence of other viruses, alcohol use and other liver stressors.
- The lifetime risk of liver cancer is estimated at 10% to 25%, and it is even higher in people with cirrhosis.
- About 15% to 25% of chronically infected people will eventually die from cirrhosis or liver cancer (hepatocellular carcinoma) if left untreated.
These risks increase among individuals infected at birth or during early childhood, making prevention, as well as ongoing monitoring and treatment, more important.
Infection control: Reducing the spread of hepatitis B
Person-to-person transmission
Hepatitis B is highly infectious. In fact, it’s estimated to be about 100 times more infectious than HIV. When someone is chronically infected with hepatitis B, their blood is teeming with viral particles and surface antigen protein. It’s estimated that most infected people have about 1 million to 1 billion viral particles in every milliliter of blood (a milliliter is about one-fifth of a teaspoon). As a result, even quantities of blood too miniscule to see with the naked eye can be sufficient to spread the virus. Infected individuals with or without symptoms, or even those with lower quantities of virus in their blood, can transmit hepatitis B virus to others. Additionally, hepatitis B spreads not just through blood, but also through certain body fluids, including semen and vaginal fluids, as well as body fluids that may contain blood, like saliva. The virus is not transmitted through casual contact, such as hugging, kissing, or sneezing or coughing.
Perinatal transmission (mother to baby at birth) is the most common route of spread globally. Because not all hepatitis B-positive mothers are identified, the birth dose of hepatitis B vaccine is critical for decreasing transmission. Without the recommended intervention of vaccination and immune globulin treatment at birth, up to 90% of infants born to infected mothers become chronically infected.
Transmission from objects
Hepatitis B virus is also hardy. It can remain infectious for up to seven days on surfaces and objects. This combination of hardiness on surfaces and presence even when blood is not able to be seen means that this virus can — and does — spread in unexpected ways. While rare, cases of hepatitis B infection have been traced back to improperly cleaned medical devices, tattooing and piercing tools, and acupuncture needles, as well as by sharing common personal items that may contain unseen quantities of blood, like toothbrushes, washcloths and razors.
Transmission through contaminated needles is one of the more common sources of spread. The U.S. opioid epidemic has led to increases in hepatitis B resulting from this. Historically, it has been difficult to vaccinate individuals at high risk of transmission due to drug use prior to exposure and to ensure all doses are received, so while programs aimed at high-risk groups can help, a vaccination program targeted solely at high-risk individuals will not eliminate this virus from the U.S.
Unanticipated risks
While transmission often occurs through more typical scenarios, such as perinatal exposure or intravenous drug use, the reality is that the amount of virus present in a small amount of blood and the ability of the virus to live on surfaces create unpredictable risks. A guest visiting someone’s home who is unaware of their infection status can leave a razor contaminated with blood on the side of a bathtub, only to be picked up by an inquisitive child. An undiagnosed infected child at day care may bite someone else, leaving a break in the skin through which blood exchange, and thus viral transmission can occur. Athletes playing contact sports, like wrestling or football, can inadvertently be exposed to blood from an infected player or coach. It is these unpredictable moments during which transmission can occur that make universal prevention approaches critical, as people infected by these routes may not have known risk factors.
Managing exposures
If someone is exposed to hepatitis B, prompt action can prevent infection — especially if they are unvaccinated or unsure of their vaccination status.
High-risk exposures, such as needlestick injuries, contact with infected blood or body fluids (especially through broken skin or mucous membranes), or birth to a hepatitis B–infected mother, need prompt attention — ideally within 24 hours because the sooner post-exposure intervention occurs, the more effective it is. The approach to post-exposure prophylaxis depends on the type of exposure, status of the source person, status of the exposed person, and the availability of vaccination records. The Centers for Disease Control and Prevention has detailed guidance for managing exposures in a 2018 Morbidity and Mortality Weekly Report (MMWR).
Hepatitis B: Key clinical takeaways
Hepatitis B is a highly contagious virus with often insidious methods of transmission. When children are exposed, they often lack symptoms and are more likely to be chronically infected. For this reason, on-time vaccination is critical. As fewer children are chronically infected because of a robust vaccination program, we will have an opportunity to eliminate hepatitis B virus. In the meantime, prompt recognition of exposures and infections can reduce spread within communities and ensure that patients gain access to any necessary specialized treatment.
Resources for families
- Hepatitis B: What You Should Know (Q&A)
- Hepatitis B (Infographic)
- 9,000 Reasons for Routine Childhood Hepatitis B Vaccination (Parents PACK article)
- Why Do Newborns Get the Hepatitis B Vaccine? (video)
- Vaccines on the Go: What You Should Know (mobile app)
- Hepatitis B Foundation
Resources for providers
- Manual for the Surveillance of Vaccine-Preventable Diseases – Chapter 4: Hepatitis B
- Responding to HBV Exposures in Health Care Settings
- Hepatitis B Foundation
- Viral Hepatitis Surveillance and Case Management: Interpretation of hepatitis B laboratory results
- Diabetes and Hepatitis B Vaccination
Contributed by: Lori Handy, MD, MSCE , Charlotte A. Moser, MS, Paul A. Offit, MD
Our Vaccine Update feature article “Fast Facts” series continues this month with a focus on hepatitis B. While most families embrace the birth dose of hepatitis B vaccine to give their infants necessary protection, pediatric providers are reporting an increase in families delaying or refusing the birth dose of hepatitis B vaccine. Additionally, comments at the June meeting of the Advisory Committee on Immunization Practices (ACIP) referenced that the current hepatitis B schedule, including the birth dose, will be reviewed — despite strong data to support its safety and effectiveness. As such, we thought this refresher could help draw attention to this virus, the disease it causes, how it's transmitted, why vaccination for hepatitis B continues to be critical, and why the birth dose matters.
Prior to introduction of a hepatitis B vaccine, about 200,000 to 300,000 new hepatitis B infections occurred each year. The introduction of vaccine has led to a significant reduction in cases. Now, about 22,000 people in the United States are diagnosed with new infections each year. About 2,000 of these people will die from their infection.
Since the first recommendations were published in 1982, they have evolved to include a universal infant recommendation as well as catch-up recommendations. The July 2025 Parents PACK feature article, “9,000 Reasons for Routine Childhood Hepatitis B Vaccination,” reviews this evolution in detail and can serve as an excellent resource when talking with families. Importantly, the evolution of recommendations to include a birth dose of vaccine has been pivotal in controlling hepatitis B in the U.S. The birth dose recommendation is not unique to the U.S. The World Health Organization (WHO) recommends a birth dose, and many countries around the world have successfully implemented hepatitis B vaccine birth dose programs. As such, changes to this approach in the U.S. will set us back and undoubtedly allow our progress against this virus to slip.
Recognizing hepatitis B
Hepatitis B virus replicates in the liver to cause acute or chronic infections. When someone is first infected with the virus, it is described as “acute.” If the person’s immune system cannot clear the virus within six months, they are considered to have a “chronic” infection. Some people, particularly young children, will not have initial symptoms, while others will experience severe illness. When symptoms do occur, they can include fatigue, jaundice, abdominal pain, and elevated liver enzymes. Infections that become chronic lead to long-term liver damage, cirrhosis (a condition in which healthy liver tissue is replaced by scar tissue), and liver cancer. While not every chronic hepatitis B infection leads to liver cancer, the risk is real. Both chronic infection and liver cancer are more likely among those infected at birth or in early childhood compared to those infected later in life.
Some groups are at higher risk of infection, including:
- Those born in regions with intermediate or high hepatitis B prevalence, such as Asia, Africa, and the Pacific Islands
- People who use injection drugs
- Men who have sex with men
- People with HIV
- Household or sexual contacts of individuals with hepatitis B
- People taking immunosuppressive therapy or undergoing dialysis
- People with diabetes
Infants born to mothers with hepatitis B are at risk of acquiring hepatitis B during delivery or in the months after birth due to close contact and the potential for exposure to a mother’s blood, such as during breastfeeding when the mother has cracked skin or nipples. Because of this high-risk period, prenatal screening is embedded in obstetric care across the U.S. to be able to counsel the pregnant person and provide prompt medical care to the infant at birth.
While it is important to know who might be at higher risk of infection, it’s important to remember that anyone can get hepatitis B. This is why the vaccine recommendations focused only on high-risk groups did not stop the spread of infection. As such, patients with relevant symptoms should be evaluated for hepatitis B.
Making a hepatitis B diagnosis
Hepatitis B is diagnosed through blood tests that detect viral markers. The key tests include:
- HBsAg (hepatitis B surface antigen): Indicates an active infection, either acute or chronic.
- Anti-HBs (hepatitis B surface antibody): Indicates recovery and immunity from hepatitis B or successful vaccination.
- Anti-HBc (hepatitis B core antibody): Indicates past or current hepatitis B infection; this antibody is not present after vaccination alone.
- IgM anti-HBc: Indicates a recent infection.
- HBV DNA (viral load): Measures how much virus is in the blood. This test is used to monitor chronic hepatitis B infection and response to treatment.
While testing may be done when someone has symptoms, infections may be silent, so screening is a critical component of detecting and diagnosing hepatitis B. Current screening recommendations include:
- Universal screening: All adults aged 18 years and older should be screened for hepatitis B at least once in their lifetime, regardless of risk factors.
- Pregnant individuals: All pregnant women should be screened during each pregnancy, ideally at the first prenatal visit, regardless of vaccination history or prior test results. Many clinicians also opt to screen again closer to delivery.
- High-risk groups: People at higher risk, as described above, should be screened periodically.
- Anyone who requests screening: Because patients are often reluctant to disclose all risk factors, those who request screening should be evaluated.
Screening usually involves using a combination of the HBsAg, anti-HBs, and total anti-HBc tests, as this triple combination can clarify infection status, immunity and susceptibility.
Finally, testing to confirm immunity from vaccination can be challenging to interpret. When vaccinated individuals test positive for hepatitis B surface antibody, this confirms that they are protected from infection. However, circulating antibodies decrease over time and, therefore, may not be measurable. Even with a negative test, patients are most often still protected long term through the presence of memory B and T cells. When confidence in protection is critical, such as for healthcare workers, the recommendation is to revaccinate and test, as discussed in our prior Vaccine Update article, “Communicating with Patients about Hepatitis B Surface Antibodies.”
Treatment and management of hepatitis B
Treatment for hepatitis B depends on whether the infection is acute or chronic, as well as pregnancy status.
- Acute hepatitis B: Most people with acute hepatitis B do not require antiviral treatment. Instead, supportive care (e.g., hydration, rest, and monitoring of liver function) is usually sufficient as most healthy adults will clear the virus on their own. However, close follow-up is essential to make sure they have recovered fully and to monitor for development of chronic infection.
- Chronic hepatitis B: Chronic infection may require long-term antiviral therapy to suppress viral replication and reduce the risk of liver damage, cirrhosis and liver cancer. Typically, an individual should be referred to a clinician experienced in prescribing oral antivirals, such as an infectious disease specialist or gastroenterologist, to discuss the risks and benefits of the medications and when it is appropriate to start treatment. The specialist can also manage monitoring needed during treatment, such as regular liver function tests, HBV DNA levels, and regular screening for hepatocellular carcinoma.
- Pregnant women with hepatitis B: When a woman has high hepatitis B viral loads, her infant may still be at risk for developing infection even with vaccination and treatment at birth. For this reason, some pregnant women are recommended to receive an oral antiviral during the third trimester to decrease the viral load prior to delivery. Regardless of whether a mother receives antiviral treatment during pregnancy, infants should promptly receive vaccine and hepatitis B immune globulin (HBIG) within 12 hours of birth.
Long-term impact
Currently, in the U.S., more than 2 million people are estimated to live with chronic hepatitis B, but 80% of these individuals are not aware of their chronic hepatitis B status.
Among people with chronic hepatitis B infection, a significant proportion develop serious liver complications over time:
- The risk of cirrhosis over a lifetime is estimated at 20% to 30%, though it varies depending on age at infection, viral load, presence of other viruses, alcohol use and other liver stressors.
- The lifetime risk of liver cancer is estimated at 10% to 25%, and it is even higher in people with cirrhosis.
- About 15% to 25% of chronically infected people will eventually die from cirrhosis or liver cancer (hepatocellular carcinoma) if left untreated.
These risks increase among individuals infected at birth or during early childhood, making prevention, as well as ongoing monitoring and treatment, more important.
Infection control: Reducing the spread of hepatitis B
Person-to-person transmission
Hepatitis B is highly infectious. In fact, it’s estimated to be about 100 times more infectious than HIV. When someone is chronically infected with hepatitis B, their blood is teeming with viral particles and surface antigen protein. It’s estimated that most infected people have about 1 million to 1 billion viral particles in every milliliter of blood (a milliliter is about one-fifth of a teaspoon). As a result, even quantities of blood too miniscule to see with the naked eye can be sufficient to spread the virus. Infected individuals with or without symptoms, or even those with lower quantities of virus in their blood, can transmit hepatitis B virus to others. Additionally, hepatitis B spreads not just through blood, but also through certain body fluids, including semen and vaginal fluids, as well as body fluids that may contain blood, like saliva. The virus is not transmitted through casual contact, such as hugging, kissing, or sneezing or coughing.
Perinatal transmission (mother to baby at birth) is the most common route of spread globally. Because not all hepatitis B-positive mothers are identified, the birth dose of hepatitis B vaccine is critical for decreasing transmission. Without the recommended intervention of vaccination and immune globulin treatment at birth, up to 90% of infants born to infected mothers become chronically infected.
Transmission from objects
Hepatitis B virus is also hardy. It can remain infectious for up to seven days on surfaces and objects. This combination of hardiness on surfaces and presence even when blood is not able to be seen means that this virus can — and does — spread in unexpected ways. While rare, cases of hepatitis B infection have been traced back to improperly cleaned medical devices, tattooing and piercing tools, and acupuncture needles, as well as by sharing common personal items that may contain unseen quantities of blood, like toothbrushes, washcloths and razors.
Transmission through contaminated needles is one of the more common sources of spread. The U.S. opioid epidemic has led to increases in hepatitis B resulting from this. Historically, it has been difficult to vaccinate individuals at high risk of transmission due to drug use prior to exposure and to ensure all doses are received, so while programs aimed at high-risk groups can help, a vaccination program targeted solely at high-risk individuals will not eliminate this virus from the U.S.
Unanticipated risks
While transmission often occurs through more typical scenarios, such as perinatal exposure or intravenous drug use, the reality is that the amount of virus present in a small amount of blood and the ability of the virus to live on surfaces create unpredictable risks. A guest visiting someone’s home who is unaware of their infection status can leave a razor contaminated with blood on the side of a bathtub, only to be picked up by an inquisitive child. An undiagnosed infected child at day care may bite someone else, leaving a break in the skin through which blood exchange, and thus viral transmission can occur. Athletes playing contact sports, like wrestling or football, can inadvertently be exposed to blood from an infected player or coach. It is these unpredictable moments during which transmission can occur that make universal prevention approaches critical, as people infected by these routes may not have known risk factors.
Managing exposures
If someone is exposed to hepatitis B, prompt action can prevent infection — especially if they are unvaccinated or unsure of their vaccination status.
High-risk exposures, such as needlestick injuries, contact with infected blood or body fluids (especially through broken skin or mucous membranes), or birth to a hepatitis B–infected mother, need prompt attention — ideally within 24 hours because the sooner post-exposure intervention occurs, the more effective it is. The approach to post-exposure prophylaxis depends on the type of exposure, status of the source person, status of the exposed person, and the availability of vaccination records. The Centers for Disease Control and Prevention has detailed guidance for managing exposures in a 2018 Morbidity and Mortality Weekly Report (MMWR).
Hepatitis B: Key clinical takeaways
Hepatitis B is a highly contagious virus with often insidious methods of transmission. When children are exposed, they often lack symptoms and are more likely to be chronically infected. For this reason, on-time vaccination is critical. As fewer children are chronically infected because of a robust vaccination program, we will have an opportunity to eliminate hepatitis B virus. In the meantime, prompt recognition of exposures and infections can reduce spread within communities and ensure that patients gain access to any necessary specialized treatment.
Resources for families
- Hepatitis B: What You Should Know (Q&A)
- Hepatitis B (Infographic)
- 9,000 Reasons for Routine Childhood Hepatitis B Vaccination (Parents PACK article)
- Why Do Newborns Get the Hepatitis B Vaccine? (video)
- Vaccines on the Go: What You Should Know (mobile app)
- Hepatitis B Foundation
Resources for providers
- Manual for the Surveillance of Vaccine-Preventable Diseases – Chapter 4: Hepatitis B
- Responding to HBV Exposures in Health Care Settings
- Hepatitis B Foundation
- Viral Hepatitis Surveillance and Case Management: Interpretation of hepatitis B laboratory results
- Diabetes and Hepatitis B Vaccination
Contributed by: Lori Handy, MD, MSCE , Charlotte A. Moser, MS, Paul A. Offit, MD