Longterm kinetics of vibriocidal antibody responses after infection in the Democratic Republic of Congo.

Interpretation of sero-epidemiology studies of cholera relies on knowledge of antibody kinetics, which thus far have been lacking in African populations. We performed vibriocidal assays on 212 serum samples from 116 culture-positive cholera patients (median age 8 (IQR 4-18)) in Goma, DRC, collected at enrollment and again 3-449 days after. Vibriocidal responses peaked 7-40 days after symptom onset, with nearly all samples declining to a titer of 160 or lower by day 180. We used a Bayesian exponential decay model to show an 88% probability of a faster decay in children under 5.