Methods: 580 pregnant Kenyan mothers were enrolled in the study and tested at prenatal visits for malaria, soil transmitted helminths, G. lamblia, S. stercoralis and S. haematobium infection. The infants received the 10-valent Streptococcus pneumonia conjugate vaccine (PCV), Haemophilus influenzae type B (Hib) and Diphtheria toxoid (DT) vaccines at 6, 10, and 14 weeks of age. Serum was collected from cord blood, 10 and 14-weeks, 6 months, and every 6 months following through the second year of life. A multiplex fluorescent bead assay determined IgG concentrations to HiB, DT, and the ten PCV serotypes: 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F and 23F.
Results: Total parasitic infection incidence among mothers in the study is high, with 373 of 580 (64.2%) participants having at least one parasitic infection during pregnancy and 75 participants (13%) with 2 or more infections. The most common infections were hookworm (19.7%), P. falciparum (16.2%), S. haematobium (11%), and T. trichiura (10.5%). In preliminary analysis using a mixed linear model comparing infection status to log (antibody concentration), we are able to see a 37% higher concentration of PCV 9V antibody in children born to mothers with infections (p=0.016) compared to uninfected mother/child pairs. S. haematobiuminfection was associated with significantly higher concentrations in 4 PCV antigens: 1 (3.9 fold higher, p=0.0006), 7 (2.3 fold higher, p=0.004), 9V (2.3 fold higher, p=0.002), and 18C (6.8 fold higher, p<0.0001).
Conclusion: Perinatal parasitic infections appear to have a significant impact on the developing fetal immune system resulting in an altered response to early childhood vaccinations.
D. Boothroyd, None
I. Malhotra, None
C. H. King, None
F. Mutuku, None
A. D. Labeaud, None