Pertussis immunisation during pregnancy: Antibody levels and the impact of booster vaccine

A phase 2 randomized controlled dose-ranging trial of recombinant pertussis booster vaccines containing genetically inactivated pertussis toxin in pregnant women

“…The protection of newborn infants via the transfer of maternal antibodies through the placenta and breastmilk would be inadequate without maternal booster immunization [19] , [20] , [21] . The substantial enhancement of maternal antibodies by a single booster dose of any of the vaccines studied here was comparable to our previous findings with the same vaccines in women of childbearing age [11] and other recent studies of Tdap8 chem vaccination in pregnancy [22] , [23] , [24] , [25] . Notably, we found no major difference in PT-IgG response and serum PT-neutralizing activity between vaccination during the second versus the third trimester of pregnancy when the responses were measured at 28 days after vaccination ( Appendix Fig.…”

mSphere of Influence: Pertussis Vaccination and Antibodies in Mothers and Infants

“…While there is no firm correlate of protection for pertussis, PT-specific IgG are necessary to prevent disease. Some have argued that PT IgG levels above 5 IU/mL could be considered to be protective ( 5 ); others have suggested a higher and more conservative cutoff level of 10 IU/mL ( 6 ), and more recently, 20 IU/mL has also been proposed ( 7 , 8 ). The analysis by Havers et al showed that the mean anti-PT IgG level in cord blood in the aP-primed group was 17.3 IU/mL, which was significantly lower (less than half) than the mean levels detected in the wP-primed (36.4 IU/mL) and mixed (31.2 IU/mL) groups.…”