Basic overview of hepatitis B virus (HBV)
Hepatitis B is a serious liver infection caused by the hepatitis B virus (HBV). While many people recover and develop lifelong immunity, about 10% of adults will develop chronic HBV infection, which can lead to cirrhosis, liver cancer, or death. The younger the age at time of infection, the higher the risk of developing chronic infection. Hepatitis B is preventable through vaccination.
Separate vaccines are available for:
- Hepatitis B only
- Combination vaccine for hepatitis A and B (Twinrix)
There is no vaccine for hepatitis C.
Impact on people who use drugs (PWUD)
- Higher risk of chronic infection due to repeated exposure
- Co-occurring conditions (e.g., HCV, HIV) can lead to more severe health impacts
- Delayed diagnosis and limited healthcare access can worsen outcomes
- Hep B vaccination reduces both personal and public health impacts
Intersection with hepatitis C (HCV)
- Many PWUD are also living with hepatitis C
- Co-infection can accelerate liver disease progression
- HBV (and HAV) vaccination is essential for those with or at risk for HCV, as it reduces the risk for more severe morbidity or mortality that is associated with acute or chronic viral hepatitis co-infections
Transmission and prevention among PWUD
HBV is spread through:
- Blood and bodily fluids (e.g., shared needles, drug equipment)
- Unprotected sex
- Birthing parent to child during childbirth
Among PWUD, risk of transmission is higher due to:
- Sharing of drug use equipment
- Unregulated/unsanitary tattooing or piercing
- Sexual activity, especially without barrier protection
Prevention includes:
- Vaccination
- Safer use practices such as not reusing or sharing equipment (injecting, smoking and snorting)
- Access to sterile supplies
- Condom use and regular STI testing
To reduce the risk of transmission to infants, all pregnant persons with hepatitis B should be monitored during pregnancy and their infant should get post exposure prophylaxis (PEP) at birth.
Why is the hepatitis B vaccine beneficial for PWUD?
- High Risk of Transmission: Drug use increases HBV exposure risk
- Chronic Disease Burden: Many PWUD are co-infected with HCV or HIV, worsening health outcomes if they contract HBV
- Long-Term Protection: The vaccine offers durable immunity, lowering long-term health risks and transmission
- Outbreak Prevention: Widespread vaccination in this group can reduce local and community-wide outbreaks
Recommendations
Hepatitis B vaccination is recommended for:
- All infants (starting at birth)
- Unvaccinated children and teens
- All adults aged 19–59
- Adults aged 60+ who have risk factors for hepatitis B infection, including injection drug use, chronic liver disease or HIV, or incarceration.
Types of vaccines
- Single-antigen Hepatitis B vaccines: 3-dose series (Engerix-B, Recombivax HB) or 2-dose series (Heplisav-B): Approved for adults 18+, completed over 1 month
- Combination A/B vaccine (Twinrix): 3-dose series, for adults 18+
Vaccination schedule
| Age | Dose | Timing |
|---|---|---|
| Infants | Dose 1 Dose 2 Dose 3 | Within 24 hours of birth At 1-2 months At 6-18 months |
| Children and Adults | Dose 1 Dose 2 Dose 3 | Any time 1-2 months later 6 months after first dose |
| Alternative for Adults | Dose 1 Dose 2 | Any time 1 month later |
| Combination A + B for Adults (Twinrix) | Dose 1 Dose 2 Dose 3 | Any time 1 month later 6 months after first dose |
If vaccination history is unknown
- Check medical records for prior doses.
- Blood test (anti-HBs) can be done to determine the person's HBV status, but there is no need to wait for the results – vaccination right after the blood test is recommended.
- If no record or antibodies, begin or complete the vaccine series.
You do not need to restart the series if doses were delayed—just complete the missing ones.
Vaccine effectiveness and duration
- 95%+ effective when full series is completed
- Protection lasts at least 20–30 years, possibly lifelong
- Some individuals (e.g., immunocompromised) may need antibody testing after vaccination
Vaccination during pregnancy and breastfeeding
- Safe for pregnant and breastfeeding individuals
- HBV vaccine should not be delayed due to pregnancy or lactation
- Pregnant individuals with HBV should be reported to DPH and referred for follow-up and infant prophylaxis
Post-exposure prophylaxis (PEP)
If someone is exposed to HBV and is unvaccinated:
- Administer HBV vaccine immediately
- Hepatitis B Immune Globulin (HBIG) may also be given within 24 hours for high-risk exposures (e.g., needlestick injuries)
Treatment for hepatitis B
- Acute HBV: Usually self-limiting; supportive care. Anyone with acute HBV should be tested 6 months later to see if the infection has become chronic.
- Chronic HBV: People with chronic HBV need regular liver function and viral load checks. This monitoring will help a provider decide if the patient needs treatment. Chronic HBV is treatable with antiviral medications that suppress the virus and reduce liver damage risk.
Intersection with hepatitis C (HCV)
- Many PWUD are also living with hepatitis C
- Co-infection can accelerate liver disease progression
- HBV (and HAV) vaccination is essential for those with or at risk for HCV