Antibody seropositivity and endemicity of chikungunya and Zika viruses in Nigeria

Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.albopictus,and malaria,a parasitic disease transmitted by Anopheles gambiae,are prevalent in Nigeria and neighbouring countries,but their burden and possible coinfections are poorly understood.In this study,we investigated the antibody seropositivity and endemicity of chikungunya and Zika viruses(ZIKV)in three regions of Nigeria.A cross-sectional serosurvey was conducted on 871 participants.Samples were collected from outpatients by simple random sampling.Analyses of the samples were performed using recomLine Tropical Fever for the presence of antibody serological marker IgG immunoblot with CHIKV VLP(virus like particle),ZIKV NS1 and ZIKV Equad according to manufacturers’instructions and malaria RDT for malaria parasite.There was a significantly higher antibody seropositivity against CHIKV in the central region than in the northern and southern regions(69.5%,291/419),while ZIKV-seropositivity(22.4%,34/152)and CHIKV-ZIKV co-circulating antibody seropositivity(17.8%,27/152)were notably higher in the southern region than in the central and northern regions.This investigation revealed an unexpectedly high antibody seropositivity and concealed endemicity of CHIKV and ZIKV in three Nigerian regions.The seropositivity of detectable antibodies differed among the three geographical locations.