Transovarial infection in Aedes Aegypti: Correlational study on incidence of dengue hemorrhagic fever (DHF) at endemic area of Semarang city, Indonesia

Abstract

Indonesia is an endemic area of DHF. The incidence in 2019 reached 70.03 / 100,000 population. The one mechanism of the dengue virus survive in nature is through transovarial infections. This mecahnism can cause the virus to persist, leading to the endemicity of dengue in a region. The aim of this study was to analyze the correlation of larval density and transovarial in Aedes aegypti with the occurrence of DHF using a spatial analysis approach. The study was correlational design, located in 11 sub villages in Meteseh village of Semarang City. The sample was 33 houses per sub village, so total sample was 363 houses. Survey of entomological method was done by examination the houses to measure indexes of larvae density and collection the eggs using ovitrap. Female Aedes aegypti from rearing eggs or lavae was used to identify transovarial infection by immunohistochemical assay. The result showed that transovarial transmission of dengue virus was found in 8 sub villages, (ITT was around 5-20%. There was a relationship between transovarial infection with the incidence of DHF (p= 0.043). This study provides information that Aedes aegypti transmit virus by transovarial infections, and the distribution of DHF has spatially related to transovarial infections.