Classroom

B73 Perinatal Hepatitis B

Key Facts

This webpage is only intended for use by staff from the Los Angeles County Department of Public Health.Page Updated 3-11-25


  • Agent: Hepatitis B virus (HBV)
  • Identification: California law (Health and Safety Code, Sections 125080-125085) requires healthcare providers test all pregnant persons for hepatitis B surface antigen (HBsAg) during each pregnancy even if they have been vaccinated or previously tested. Repeat HBsAg testing on HBsAg negative persons at the time of delivery if the person has clinical hepatitis or is at risk for hepatitis B exposure during pregnancy. Risk factors include:
    1. recent intravenous drug use
    2. HBsAg positive sex partner
    3. more than one sex partner in the past 6 months, or
    4. treatment for a sexually transmitted disease.
  • Hospitals should accept only original laboratory reports as documentation of a person’s HBsAg status. Labs performed outside of the United States are not acceptable. The Center for Disease Control and Prevention (CDC) also recommends testing all HBsAg positive pregnant persons for hepatitis B virus deoxyribonucleic acid (HBV DNA).
    1. Symptoms: While acute cases of hepatitis B can occur in the prenatal period, most HBsAg positive prenatal patients are asymptomatic chronic carriers and identified by their laboratory test only. Infants infected are generally asymptomatic.
    2. Differential Diagnosis: Other viral, chemical, and other causes of hepatitis.
    3. Diagnosis: Confirmed HBsAg lab result. Infant’s blood will contain maternal anti-HBc IgG at birth, but does not indicate maternal-infant transmission.
  • Incubation From 45-180 days.
  • Reservoir: Human.
  • Source: For infants, maternal blood or body fluids.
  • Transmission: Exposure usually occurs during the birth process, but transmission can occur in utero (rare). Vaginal or caesarean deliveries have similar transmission risks.
  • Communicability: Maternal blood or body fluids are potentially infectious. Infants infected in utero are usually non-infectious at birth, since they are incubating the disease.
  • Specific Treatment: Treatment for pregnant persons with chronic hepatitis B infection is available for some patients who meet clinical criteria to prevent perinatal transmission. Prophylaxis (HBIG and Hepatitis B vaccine) is recommended for infants born to HBsAg positive persons.
Specific Treatment
Pregnant Persons with Increased Viral Loads
  1. Test all HBsAg positive pregnant persons for HBV DNA to guide the use of maternal anti–viral therapy during pregnancy. Infants born to pregnant persons with high viral loads are at greatest risk for infection despite receipt of hep B vaccine and HBIG.
  2. Refer pregnant persons with HBV DNA levels > 20,000 IU/mL to a liver or infectious disease specialist for evaluation.
  3. Evaluate pregnant - persons with HBV DNA levels >200,000 IU/mL, for antiviral therapy at 28–32 weeks until the infant is delivered to prevent perinatal transmission. See CDC’s Obstetrical Tip Sheet for Hepatitis B Screening, Testing and Management of Pregnant Persons for details.
Infants born to HBsAg-Positive Persons

Timely administration of hepatitis B vaccine and hepatitis B immune globulin (HBIG) to infants born to HBsAg-positive persons is recommended to prevent maternal-infant transmission of hepatitis B.

  1. Administer single–antigen hep B vaccine (Engerix or Recombivax) and HBIG in separate limbs intramuscularly (IM) within 12 hours of birth. Complete the hep B vaccine series per ACIP recommendations. 
  2. Administer hep B vaccine and HBIG within 12 hours of birth to infants weighing <2000 grams . Complete the hep B vaccine series per ACIP recommendations.
  3. Infants being transferred to another facility, should receive PEP prior to transfer. If the transferring hospital is unable to administer PEP prior to the transfer, communicate the infant’s status with the receiving hospital to ensure prophylaxis is administered in a timely manner.
  4. Details regarding the vaccination schedule for infants by birthweight and maternal HBsAg status can be found here.
  5. Post-vaccination serology (PVS) testing is recommended at age 9-12 months or 1–2 months after the final hep B dose if the series is delayed. PVS testing includes the following lab tests:
    1. HBsAg
    2. anti – HBs, Quantitative (antibody to hepatitis B surface antigen)
Infants born to Persons with Unknown HBsAg Status
  1. Persons admitted for delivery without a documented HBsAg result should have blood drawn and tested as soon as possible.
  2. Administer single-antigen hep B vaccine (Engerix or Recombivax) to infants weighing ≥2000 grams within 12 hours of birth.
    1. If the mother is found to be HBsAg positive, administer HBIG to the infant as soon as possible but no later than 7 days of birth.
  3. Administer HBIG and single-antigen hep B vaccine within 12 hours of birth to premature infants weighing <2000 grams.
  4. If it is not possible to determine the birth parent’s HBsAg status (e.g. parent safely surrenders infant), the vaccine series should be completed according to the recommendations for infants born to HBsAg positive persons. Post – vaccination serology testing is recommended at 9–12 months of age or 1–2 months after the last hep B dose. PVS testing includes the following lab tests:
    1. HBsAg
    2. anti – HBs, Quantitative
Infants born to Persons with a Negative HBsAg Status
  1. Administer a dose of single-antigen hep B vaccine to all full-term infants who are medically stable and weigh at least 2,000 grams (4.4 pounds) within 24 hours of birth. Only single antigen Hepatitis B vaccine (Engerix or Recombivax) should be used for the birth dose.
  2. Administer two additional doses of hepatitis B vaccine at 1-2 months and 6 months of age.
  3. Administer the first dose of hep B vaccine at chronological age 1 month or hospital discharge for infants weighing less than 2000 grams (whichever is earlier, even if weight is still <2000 grams).
  4. Complete the hep B vaccine series according to ACIP recommendations.
Reporting Procedures
Reporting for Healthcare Providers and Laboratories

Title 17, California Code of Regulations (CCR), Section 2500 requires healthcare providers report HBsAg-positive results to the local health department within 7 days. CCR, Title 17, Section 2505 requires laboratories report HBsAg-positive and HBV DNA results (must specify gender) to the local health department within one (1) working day.

Reporting Births

Report all births of persons with a positive or unknown HBsAg status to the Perinatal Hepatitis B Prevention Unit (PHBPU) at the Los Angeles County Department of Public Health, Vaccine Preventable Disease Control Program within 24 hours of birth. Send report via vax to (213) 351-2781 or secure email at VPDC-PHB@ph.lacounty.gov.

Report Form & Epidemiologic Data

CONFIDENTIAL HBsAg+ CASE/HOUSEHOLD MANAGEMENT REPORT (CDPH 8546).

Epidemiologic Data:
Obtain the following information to evaluate risk of transmission to the infant and household and sexual contacts:

  1. Estimated delivery date and anticipated delivery hospital.
  2. HBV DNA laboratory results
  3. Anticipated pediatric care provider.
  4. Screen household and sexual contacts to for susceptibility and need for vaccination.
    1. Obtain laboratory results or vaccination history for all household and sexual contacts.
    2. Household contact(s) – obtain the following tests to determine susceptibility to hepatitis B:
      1. anti – HBs Quantitative
      2. HBsAg
Control of Case, Contacts & Carriers
Control of Case, Contacts & Carriers

Follow – up on infants born to HBsAg – positive persons immediately after birth to ensure receipt of HBIG and hep B vaccine within 12 hours of birth.

Case Investigation

Follow-up of newborn is a public health priority. Without appropriate protection, up to 90% of newborns will develop chronic hepatitis B if they do not receive the appropriate prophylaxis after birth.

Post-Vaccination Serology Testing: Test all infants born to HBsAg positive persons for both HBsAg and HBsAb (anti-HBs) 1-2 months after vaccine series is completed, but not before 9 months of age.

Revaccinate HBsAg negative infants with anti-HBs levels <10 mIU/mL with a single dose of hepatitis B vaccine and retest 1-2 months later. If the anti – HBs remain <10 mIU/mL, administer the remaining two doses in the series and retest 1 – 2 months after the final dose. Alternatively, these infants may be revaccinated with a second 3-dose series and retested (anti - HBs) 1–2 months after the final dose of vaccine.

Additional doses of hep B vaccine are not recommended for infants who fail to seroconvert (anti – HBs <10 mIU/mL) after the completion of two (2)  three – dose series.

Contacts

Investigate remaining contacts within 2 weeks (persons exposed to blood or body fluid of an infected person, regular sexual partners, and long-term household contacts to a carrier of hepatitis B). "Long-term" contacts are defined as individuals with anticipated continuous household exposure for greater than one year (often limited to nuclear family only).

  1. Regular sexual partners are at increased risk. Obtain HBsAg and anti-HBs (Quantitative) to evaluate susceptibility. If susceptible, administer hepatitis B vaccine.
  2. Long-term household contacts of all ages are at increased risk. Obtain hep B vaccination history; if unable to obtain vaccination history, obtain serologic screening (anti-HBs and HBsAg) on all contacts, including children, to evaluate status and susceptibility. If contacts are susceptible, administer hep B vaccine. Serologic testing should not be a barrier to vaccination of susceptible persons. The first dose of vaccine should typically be administered immediately after collection of the blood for serologic testing.
  3. Vaccinate without screening regular sexual partners and long-term household contacts who refuse screening for susceptibility.
  4. Vaccine dosage depends on the age and vaccine manufacturer. Refer to Hepatitis B Vaccine for Public and Providers page for the hep B vaccine schedule and dose recommendations.
Prevention - Education
  1. Advise HBsAg positive pregnant persons on the following:
    1. Additional testing for HBV DNA testing is recommended during pregnancy. Patients should also be evaluated by a liver or infectious disease specialist soon after infection is identified for possible liver disease and treatment.
    2. Post-exposure prophylaxis (PEP) for infants within 12 hours of birth to protect against the virus.
    3. Completing the hep B vaccine series and post-vaccination serology testing at 9–12 months of age is recommended to determine immunity.
    4. Breastfeeding is not contraindicated for infants who received PEP (HBIG and hep B vaccine).
    5. Use universal precautions to dispose of blood and other body secretions. Advise against sharing articles contaminated with blood (e.g., needles, syringes, razors, toothbrushes, and pedicure equipment) as they may transmit the disease.
    6. Reduce the risk of infection for sexual partners by practicing safe sex e.g., using condoms consistently and limiting the number of sex partners. Regular sexual contacts should be evaluated for susceptibility and vaccinated if necessary.
    7. Encourage long-term household contacts to be evaluated for susceptibility and vaccination, if necessary.
Diagnostic Procedures

Clinical and epidemiological history required to aid laboratory in test(s) selection.

Serology:
Container: VR serology contains a serum separator tube (SST, a red-gray top vacutainer tube) and a PUBLIC HEALTH LABORATORY FORM.

Examination Requested:

  1. For prenatal patients: Clearly label the laboratory slip as a prenatal specimen. Test required: HBsAg.
  2. For sexual or household contacts: Clearly label the laboratory slip “Hepatitis B Contact-Prenatal.” Perform the following tests on contacts: HBsAb (Quantitative) and HBsAg.
  3. For post-vaccination serology (PVS) of infants: Clearly label the laboratory slip “Hepatitis B Post-Vaccination of Infant.” Perform the following tests: HBsAb (Quantitative) and HBsAg.

Material: Whole clotted blood.

Amount: 5-7 ml.

Storage: Refrigerate.



Public Health has made reasonable efforts to provide accurate translation. However, no computerized translation is perfect and is not intended to replace traditional translation methods. If questions arise concerning the accuracy of the information, please refer to the English edition of the website, which is the official version.

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