Figure 3. Seroneutralization activity of NiV pseudoparticle infection by human sera collected from Cameroon villagers with documented differential exposure to bats.

Box-and-whisker plots showing the normalized % infection of Vero cells by VSVpp (isogenic control, striped pattern box) and NiVpp (white box) in the presence of sera diluted 1:100 from the indicated sample groups (Panels 1–5). (a) All infections were normalized to the infectivity observed for NiVpp in the presence of the fetal calf serum (FCS) negative control (set at 100%); (b) normal human sera (NHS) from Los Angeles blood donors served as additional negative controls; (c) hyperimmune rabbit anti-NiV sera (positive control); (d,e) human sera from the bat-exposed (n=227) or non-exposed (n=260) cohort of Cameroon villagers, respectively. For the bat-exposed group, the Dunnett’s test could stratify the NiVpp SN results into seropositive (n=7, median bar in red) and seronegative (n=220, median bar in yellow) subsets. In contrast, in the non-bat-exposed group, the Dunnett’s test could not identify any serum sample as being significantly different from the negative control group (FCS; e), asterisk indicates no seropositive samples). Boxes encompass the first and the third quartiles, and the solid horizontal lines within the boxes represent the median values. The whiskers represent the lowest and highest values in each sample group. The data for individual serum samples (n=487), each tested in quadruplicates, are shown in Supplementary Fig. 2b and c.