CD40LG and infection: At dilutions ≥1:256 indicative of probable infections, seroprevalence and weighted seroprevalence were of 4.0% (45/11112) and 4.7% (95%CI, 3.4–5.9%), respectively, which gave potential to six recent or active infections of putative gestational onset (Phase 2 IgM ≥ 1:48).