Antibodies toAedes aegyptiD7L salivary proteins as a new serological tool to estimate human exposure toAedesmosquitoes

Abstract

1AbstractIntroductionAedes spp.are the most prolific mosquito vectors in the world. Found on every continent, they can effectively transmit various arboviruses, including the dengue virus which continues to cause outbreaks worldwide and is spreading into previously non-endemic areas. The lack of widely available dengue vaccines accentuates the importance of targeted vector control strategies to reduce the dengue burden. High-throughput sensitive tools to estimate human-mosquito contact and evaluate vector control interventions are lacking. We propose a novel serological tool that allows rapid screening of large human cohorts for exposure to potentially infectious mosquitoes and effective targeting of vector control.MethodsWe tested 563 serum samples from a longitudinal pediatric cohort study previously conducted in Cambodia. Children enrolled in the study were dengue-naïve at baseline and were followed biannually for dengue incidence for two years. We used Western blotting and enzyme-linked immunosorbent assays to identify the most immunogenicAedes aegyptisalivary proteins and measure total anti-Ae. AegyptiIgG.ResultsWe found a strong correlation (rs=0.86) between the combined IgG responses against AeD7L1 and AeD7L2 recombinant proteins and those to whole salivary gland homogenate. We observed seasonal fluctuations of AeD7L1+2 IgG responses, corresponding toAedes spp.abundance in the region, and no cross-reactivity withCulex quinquefasciatusandAnopheles dirusmosquitoes. The baseline median AeD7L1+2 IgG responses for young children were higher in those who developed asymptomatic dengue versus those who developed symptomatic dengue.ConclusionThe IgG response against AeD7L1+2 recombinant proteins is a highly sensitive andAedesspecific marker of human exposure toAedesbites that can facilitate standardization of future serosurveys and epidemiological studies by its ability to provide a robust estimation of human-mosquito contact in a high-throughput fashion.