Use of Anti-Aedes aegypti Salivary Extract Antibody Concentration to Correlate Risk of Vector Exposure and Dengue Transmission Risk in Colombia

Abstract

Norte de Santander is a region in Colombia with a high incidence of dengue virus (DENV). In this study, we examined the serum concentration of anti-Aedes salivary gland extract (SGE) antibodies as a biomarker of DENV infection and transmission, and assessed the duration of anti-SGE antibody concentration after exposure to the vector ceased. We also determined whether SGE antibody concentration could differentiate between positive and negative DENV infected individuals and whether there are differences in exposure for each DENV serotype. We observed a significant decrease in the concentration of IgG antibodies at least 40 days after returning to an “Ae. aegypti-free” area. In addition, we found significantly higher anti-SGE IgG concentrations in DENV positive patients with some difference in exposure to mosquito bites among DENV serotypes. We conclude that the concentration of IgG antibodies against SGE is an accurate indicator of risk of dengue virus transmission and disease presence.

Concentración de los anticuerpos en contra de proteínas de las glándulas salivares de Aedes aegypti e historia de la exposición al virus del dengue en residentes de una zona endémica colombiana

“…Aedes aegypti (Rockefeller strain) mosquito dissection and salivary gland extract (SGE) preparation was performed as published elsewhere (7,8). Protein concentration was determined using the Thermo Scientific NanoDrop™ (Thermo Fisher Scientific, Wilmington, DE).…”

“…Detection of anti-SGE antibodies was optimized and tested following the methods published elsewhere (7,8). Samples were tested in duplicate.…”

“…Previous studies have shown that the type and concentration of antibodies against vector salivary gland extract (SGE) can serve as markers for disease transmission and risk (7)(8)(9)(10) and to evaluate the efficacy of vector control efforts (11,12). Additionally, estimating the prevalence of antibodies against all DENV serotypes that have circulated in a specific area gives insight of the population exposure to the virus (13).…”

Long-Lasting Permethrin-Impregnated Clothing Protects Against Mosquito Bites in Outdoor Workers

“…19 Saliva contains physiologically active chemicals able to induce humoral immune responses that can be measured. 20 Previous studies have shown that antibodies against vector salivary proteins can serve as markers for disease risk [21][22][23] and can be used to evaluate the efficacy of vector control efforts. 24,25 Our previous studies have shown increased antibody titers to salivary proteins in subjects with malaria or dengue, compared with subjects living in the same region but with no sign of infection.…”

“…24,25 Our previous studies have shown increased antibody titers to salivary proteins in subjects with malaria or dengue, compared with subjects living in the same region but with no sign of infection. 21,22 There have been a number of studies validating the detection of anti-mosquito salivary proteins as biomarkers for mosquito bite exposure. 21,[24][25][26][27][28][29][30] Although the different studies have all used different methods to assess immune response to mosquito salivary proteins, all suggest that antibodies to mosquito salivary proteins are effective biomarkers for exposure.…”