Newborn Vaccine Timeline
All newborns should receive hepatitis B vaccine at birth before hospital discharge, followed by a structured series of vaccines at 2,4,6,12-15, and 18 months of age to protect against life-threatening infectious diseases. 1
Birth (Before Hospital Discharge)
Hepatitis B (HepB) - First Dose:
- Must be administered before hospital discharge to all medically stable newborns weighing ≥2,000 g 1
- For infants born to HBsAg-positive mothers: Give HepB vaccine PLUS hepatitis B immune globulin (HBIG) within 12 hours of birth, regardless of birth weight 1, 2
- Critical timing: Delaying beyond 24 hours significantly reduces effectiveness in preventing vertical transmission 2
- For preterm infants <2,000 g born to HBsAg-negative mothers: Defer the birth dose until 1 month of age or hospital discharge; this birth dose will NOT count toward the series (they will need 4 total doses) 3, 4
2 Months of Age
Six vaccines are due simultaneously at this visit: 1, 4
- Hepatitis B (HepB) - Second Dose 1, 4
- DTaP (Diphtheria, Tetanus, acellular Pertussis) - First Dose 1, 4
- Hib (Haemophilus influenzae type b) - First Dose 1, 4
- PCV (Pneumococcal conjugate vaccine) - First Dose 1, 4
- IPV (Inactivated Poliovirus) - First Dose 1, 4
- Rotavirus - First Dose (must not be started after 14 weeks 6 days of age) 1, 4
Rationale for 2-month timing: This represents the earliest age at which most vaccines can safely stimulate the infant immune system without excessive maternal antibody interference, while protecting during the period of maximum vulnerability to life-threatening infections 1
4 Months of Age
Five vaccines (repeat series from 2 months, excluding HepB): 1
- DTaP - Second Dose 1
- Hib - Second Dose 1
- PCV - Second Dose 1
- IPV - Second Dose 1
- Rotavirus - Second Dose 1
Minimum interval: At least 4 weeks must elapse between doses to allow immune memory cells to develop while maintaining continuous antigenic stimulation 1
6 Months of Age
Six vaccines due: 1
- Hepatitis B (HepB) - Third Dose (acceptable range: 6-18 months, but earlier completion preferred) 3, 1
- DTaP - Third Dose 1
- Hib - Third Dose (NOTE: If PRP-OMP/PedvaxHIB was used, this dose is NOT needed) 1, 4
- PCV - Third Dose 1
- Rotavirus - Third Dose (depending on brand; must be completed by 8 months of age) 1
- Influenza - First Dose (begin annually starting at 6 months; children <9 years receiving for first time need 2 doses separated by at least 4 weeks) 1
12-15 Months of Age
Five vaccines due: 1
- MMR (Measles, Mumps, Rubella) - First Dose 1
- Varicella - First Dose 1
- Hepatitis A (HepA) - First Dose (acceptable range: 12-23 months, with second dose 6 months later) 1
- DTaP - Fourth Dose (can be given as early as 12 months if 6 months have elapsed since third dose) 3, 1
- Hib - Fourth Dose (final dose must be given after 12 months of age) 1
15-18 Months of Age
Catch-up window for DTaP fourth dose if not given at 12 months 3, 1
4-6 Years of Age (School Entry)
Four vaccines due: 1
Important note: The fifth DTaP dose must be given after age 4 years to ensure adequate long-term protection 1
Critical Timing Principles
Multiple doses are essential because:
- A single dose rarely produces adequate or sustained antibody levels in young infants 1
- The three-dose primary series achieves seroconversion rates of 96-100% when the schedule is followed correctly 1
- Spacing doses at approximately 4-week intervals allows sufficient time for immune memory development 1
Rotavirus has strict age constraints:
- Must be initiated between 6-14 weeks due to theoretical increased risk of intussusception if started later 1
- Final dose must be completed by 8 months of age 1
Common pitfall: Not counting the birth dose of HepB in preterm infants <2,000 g—these infants require 4 total doses, not 3 3, 4
Special Populations
Preterm infants (general rule):
- Vaccinate at chronological age (2 months, 4 months, etc.), NOT corrected gestational age 5, 6
- Exception: HepB birth dose in infants <2,000 g born to HBsAg-negative mothers should be deferred 3
- Preterm infants <32 weeks gestational age may experience apnea/bradycardia within 48 hours post-vaccination; consider cardiorespiratory monitoring for first doses 5
Infants of HBsAg-positive mothers:
- HepB vaccine + HBIG within 12 hours of birth (regardless of weight) 1, 2
- Second dose at 1 month, third dose at 6 months 3
- Test for HBsAg and anti-HBs at 9-15 months to identify chronic infection or need for revaccination 1
Catch-up schedules: