Seroepidemiological Reconstruction of Long-term Chikungunya Virus Circulation in Burkina Faso and Gabon

Abstract

Chikungunya virus (CHIKV) is a major public health concern worldwide. However, infection levels are rarely known, especially in Africa. We recruited individuals from Ouagadougou, Burkina Faso and Lambaréné, Gabon (age range: 1-55), tested their blood for CHIKV antibodies and used serocatalytic models to reconstruct epidemiological histories. In Ouagadougou, 291/999 (29.1%) individuals were seropositive, ranging from 2% among those <10y to 66% in those 40-55y. We estimated there were 7 outbreaks since the 1970s but none since 2001 resulting in 600,000 infections in the city, none of which were reported. However, we could not definitively conclude whether infections were due to CHIKV or o’nyong-nyong, another alphavirus. In Lambaréné, 117/427 (27%) participants were seropositive. Our model identified a single outbreak sometime since 2007, consistent with the only reported CHIKV outbreak in the country. These findings suggest sporadic outbreaks in these settings and that the burden remains undetected or incorrectly attributed.

Results of a nationally representative seroprevalence survey of chikungunya virus in Bangladesh

“…A strong correlation of serostatus by household has also been observed with dengue virus [31]. Sex was another notable predictor, consistent with results from both Bangladesh and elsewhere that have consistently shown infection risk is higher among females [19,30,[32][33][34]. It has been suggested that 4 differences in mobility patterns may explain this increased risk, with women in Bangladesh spending more time in and around the home where mosquitoes reside [30].…”

“…To determine CHIKV seropositive we first calculated the ratio between the fluorescence intensity to CHIKV and the control MGMT protein, and used a cut point of 5.5 to identify those with a history of CHIKV exposure (Figure S1). It has previously been estimated that a ratio of 5.5 on a linear scale (~1.70 log scale) is the threshold for the MMIA to achieve 95% sensitivity and specificity (personal communication) [19].…”

“…Limited access to testing and misdiagnoses mean that entire CHIKV epidemics are frequently missed, especially in lower-middle-income countries [19,20] and we rarely have a good understanding of the underlying burden from CHIKV in any affected setting, as well as individual-, household- and population-level predictors of infection risk. This critical knowledge gap means we do not know where to appropriately target interventions.…”

Development of Multiplex Molecular Assays for Simultaneous Detection of Dengue Serotypes and Chikungunya Virus for Arbovirus Surveillance

“…In Burkina Faso, DENV is the main endemic arbovirus included in the diagnostic and surveillance protocols, which explains the difficulty of obtaining CHIKV-positive samples. Only one seroprevalence study on CHIKV has been documented [ 16 ]. These multiplexed methods will help to improve early detection and effective surveillance of CHIKV in both humans and vectors.…”

“…In 2017, a prevalence of 28.54% of dengue fever was reported among pregnant women in Ouagadougou [ 15 ]. Another sero-epidemiological study of CHIKV was conducted in Ouagadougou, Burkina Faso, with blood samples collected in 2015, and a seroprevalence of 29.1% was reported [ 16 ]. These consecutive reports in different populations (general and pregnant populations) suggest a considerable dengue burden in Burkina Faso.…”