Consistent with a likely trophic effect of chloroquine or amodiaquine on parvovirus B19 (B19V) replication, B19V PCR/IgM positivity had the highest odds ratio (95% confidence interval) of 75.8 (15.4–526), followed by P. falciparum infection (19.4 (6.7–62.6)), vitamin A deficiency (13.5 (5.4–37.7)), body mass index-for-age z-score <2.0 (8.4 (2.7–27.0)) and incomplete vaccination (2.94 (1.3–7.2)). This evidence concerns the gene CD40LG and vitamin A deficiency.