What vaccine is recommended for newborns?

Hepatitis B Vaccine for Newborns

All newborns should receive the hepatitis B vaccine as the first and most critical immunization, with the initial dose administered within 24 hours of birth for medically stable infants ≥2,000 grams born to HBsAg-negative mothers. 1, 2

Universal Birth Dose Recommendation

The hepatitis B vaccine is the only vaccine routinely recommended for newborns in the immediate postnatal period, serving as a critical safety net to prevent perinatal transmission and the devastating long-term consequences of chronic infection, including cirrhosis and hepatocellular carcinoma. 2, 3

• The Advisory Committee on Immunization Practices (ACIP) changed the recommendation from "at hospital discharge" to "within 24 hours of birth" to emphasize early administration regardless of birthing location. 1
• Only single-antigen hepatitis B vaccine should be used for the birth dose. 1
• The hepatitis B vaccine is recognized by the CDC as the first anti-cancer vaccine because it prevents primary liver cancer. 3

Algorithm Based on Maternal HBsAg Status and Birth Weight

For Infants Born to HBsAg-Positive Mothers

These infants require both hepatitis B vaccine AND hepatitis B immune globulin (HBIG 0.5 mL) within 12 hours of birth at different injection sites, regardless of birth weight. 1, 2, 4

• For infants ≥2,000 grams: The birth dose counts as part of the standard 3-dose series (birth, 1-2 months, 6 months). 1
• For infants <2,000 grams: The birth dose does NOT count toward the vaccine series due to reduced immunogenicity—these infants require 4 total doses (birth dose plus 3 additional doses starting at 1 month of age). 2, 4
• Postvaccination serologic testing (anti-HBs and HBsAg) is mandatory at 9-12 months of age. 1, 4

For Infants Born to HBsAg-Negative Mothers

Medically stable infants ≥2,000 grams should receive the first dose within 24 hours of birth, which counts as part of the 3-dose series. 1, 2

• Infants <2,000 grams should delay the first dose until hospital discharge or 1 month of age (whichever comes first) because they have significantly reduced immunogenicity when vaccinated in the first week of life (77% seroconversion vs. 98% in term infants). 1, 2, 4
• A copy of the original laboratory report documenting maternal HBsAg-negative status must be placed in the infant's medical record. 1, 4

For Infants Born to Mothers with Unknown HBsAg Status

Infants ≥2,000 grams should receive hepatitis B vaccine within 12 hours of birth while maternal testing is expedited. 2

• If maternal HBsAg status cannot be determined within 12 hours, administer HBIG in addition to the vaccine (no later than 7 days of age). 1

Complete Vaccination Series

The complete infant series consists of 3-4 doses depending on maternal HBsAg status and birth weight. 2

• The final dose in the vaccine series should not be administered before age 24 weeks (164 days) to ensure optimal immunogenicity. 1, 2
• For infants born to HBsAg-negative mothers: Birth dose, followed by doses at 1-2 months and 6 months. 1, 2
• Protective efficacy against the chronic carrier state is 95% when the series is completed. 3

Immunologic Basis and Long-Term Protection

Antibody titers ≥10 mIU/mL against HBsAg confer protection against hepatitis B infection. 3

• Immunologic memory persists for 30 years or more in vaccine responders, even when antibody levels decline below the protective threshold. 2
• 88% of individuals who received the complete 3-dose series as children develop an anamnestic response when given a challenge dose 30 years later, indicating persistent cellular immunity. 2
• Seroprotection rates reach 96-100% in healthy infants who complete the series. 3

Critical Pitfalls to Avoid

Never assume maternal HBsAg status is accurate without verification—documentation errors, false-negative results, or acute maternal infection can occur between testing and delivery. 2

Never delay the birth dose beyond 24 hours for eligible infants (≥2,000 grams, HBsAg-negative mothers), as timing is critical for preventing perinatal transmission, particularly when maternal status is unknown or positive. 2, 5

Never count the birth dose in low birth weight infants (<2,000 grams) born to HBsAg-positive mothers as part of the vaccine series—these infants require 4 total doses due to reduced immunogenicity. 2, 4

Facility Transfer Communication

For infants transferred to a different facility after birth (e.g., a hospital with a higher level of neonatal care), staff at both the transferring and receiving facilities must communicate regarding the infant's hepatitis B vaccination and HBIG receipt status to ensure prophylaxis is administered in a timely manner. 1, 2

Post-Vaccination Testing

Routine post-vaccination serologic testing is NOT recommended for healthy infants born to HBsAg-negative mothers. 6

• Testing is reserved only for infants born to HBsAg-positive mothers, healthcare personnel, hemodialysis patients, HIV-infected persons, and other immunocompromised individuals. 6
• For infants born to HBsAg-positive mothers, testing should not be performed before 9 months of age to avoid detecting passive anti-HBs from HBIG administered at birth. 1, 4