Hepatitis B, Perinatal Infection
2017 Case Definition

Background

Great progress has been made in identifying hepatitis B surface antigen (HBsAg)-positive pregnant women and immunizing their infants with Hepatitis B (HepB) vaccine and Hepatitis B immune globulin (HBIG) to prevent vertical infection, but there are still infants who acquire hepatitis B virus (HBV)
infection. This is because either their mothers are not recognized as infected and the infant does not receive HBIG and the full Hep B vaccine series or
the intervention does not prevent infection. Without post-exposure prophylaxis with HBIG and HepB vaccine, approximately 45% of infants born to
HBV-infected mothers will become infected and up to 90% of those infected will develop chronic, life-long infection. Among infants who do develop
infection, 25% will die prematurely of liver cirrhosis or cancer. It is estimated that 1,000 newborns are infected annually.¹ Although, treatment of HBV
infection is now possible and can attenuate the impact of infection, hepatitis B cannot yet be cured.²

It is important to assure adequate immunity in infants of HBV-infected mothers and to determine if infection of the infant occurred with or without
post-exposure prophylaxis. The Centers for Disease Control and Prevention (CDC) and the Advisory Committee on Immunization Practices (ACIP) recommend universal testing of pregnant women for HBsAg, post-exposure prophylaxis within 12 hours of birth with HBIG and the first dose of HepB vaccine for infants born to HBV-infected mothers, universal birth dose administration to all infants regardless of the mother’s HBsAg status, completion of a valid three dose vaccine series in all infants, and post-vaccination serologic testing (PVST) for HBsAg and anti-HBs at 9-12 months for infants born to HBV-infected mothers or infants born in regions of high and intermediate HBV endemicity.³ The CDC Perinatal Hepatitis B Prevention Program helps promote these recommendations and provides case management of HBV-infected mothers and their infants. Evaluation of the program depends on the follow-up of exposed infants.

Clinical Criteria

Perinatal HBV infection in a child ≤ 24 months of age may range from asymptomatic to fulminant hepatitis.

Laboratory Criteria For Diagnosis

Laboratory evidence of HBV infection in an infant consists of one or more of the following:

• positive hepatitis B surface antigen (HBsAg) test (only if at least 4 weeks after last dose of Hep B vaccine)
• positive hepatitis B e antigen (HBeAg) test
• detectable HBV DNA

Epidemiologic Linkage

Born to a HBV-infected mother.

Probable

Child born in the US and positive for HBsAg at ≥ 1 month of age and ≤ 24 months of age OR positive for HBeAg or HBV DNA ≥9 months of age and ≤ 24 months of
age, but whose mother’s hepatitis B status is unknown (i.e. epidemiologic linkage not present).

Confirmed

Child born in the US to a HBV-infected mother and positive for HBsAg at ≥ 1 month of age and ≤ 24 months of age OR positive for HBeAg or HBV DNA ≥9 months of age and ≤ 24 months of age.

• Hepatitis B, Perinatal Virus Infection | 1995 Case Definition