Bordetella pertussis IgG level among pregnant women and their newborns in Najran, Southwestern, Saudi Arabia, an evidence for urgent update of the local maternal vaccination guidelines

Abstract

Objective: To determine the pertussis IgG among pregnant women and their newborns at delivery in Najran Maternity and Children Hospital, Saudi Arabia. Methods: paired maternal-neonatal cord blood samples collected at delivery between November 2016 and July 2017 at Najran Maternity and Children hospital. Using ELISA, sera analyzed for pertussis IgG. According to the manufacturer instructions (Diagnostic Automation, INC, DA-B. Pertussis IgG, USA). Results: Out of 271 samples, the maternal mean age was 28 years (range 16-46) and that of gestation age was 38.5 weeks (range 33-42). Forty mothers (14.76%) were seropositive, thirty-five (12.91%) were borderline and 196 (72.32%) were seronegative. Only two (0.73%) infants were seropositive and their maternal antibodies were > 40 U/ml. Conclusion: this is the first report of maternal pertussis immunity from Saudi Arabia, which will stimulate serious discussion on updating maternal vaccination policy in our country. Maternal immunization with Tdap before pregnancy or during the second or third trimester could provide protective immunity to the newborns, covering the gap between birth and the first dose of Tdap. However, still further larger research on safety and effectiveness of maternal vaccination would be very valuable.