Immune impacts of infant whole-cell and acellular pertussis vaccination on co-administered vaccines

Area of Science:

• Immunology
• Vaccinology
• Pediatrics

Background:

• Infant immunization schedules are critical for preventing infectious diseases.
• Pertussis vaccines are available in whole-cell (wP) and acellular (aP) formulations, with different immunogenicity profiles.
• Comparing mixed wP/aP schedules with aP-only schedules is important for optimizing infant immune responses.

Purpose of the Study:

• To compare the antibody responses to co-administered vaccine antigens in infants receiving a mixed wP/aP primary series versus an aP-only primary schedule.
• To determine if the mixed wP/aP schedule is non-inferior to the aP-only schedule for eliciting immune responses to other vaccine antigens.

Main Methods:

• A randomized controlled trial involving 150 Australian infants.
• Infants were assigned to either a mixed wP/aP schedule or an aP-only schedule for primary immunization.
• Antibody responses to 13-valent pneumococcal conjugate vaccine (13vPCV), Haemophilus influenzae type b (Hib), and hepatitis B surface antigen (HBsAg) were assessed at multiple time points.

Main Results:

• Antibody responses to all 13vPCV serotypes and Hib-PRP were non-inferior between the two schedules.
• Responses to HBsAg were also non-inferior at the assessed time points.
• The mixed wP/aP schedule demonstrated comparable immunogenicity to the aP-only schedule for co-administered antigens.

Conclusions:

• A mixed wP/aP schedule is non-inferior to the standard aP-only schedule for primary pertussis immunization in infants.
• This mixed schedule elicits comparable IgG responses to co-administered vaccine antigens, including pneumococcal and Hib vaccines.
• The findings support the flexibility in choosing pertussis vaccine schedules for infant immunization programs.