Principal Investigator: Isra Wahid, Universitas Hasanuddin
NIH-Supported Collaborator: David Severson, University of Notre Dame
Title of NIH Award: Diapause in Culex mosquitoes
Arthropod-borne viruses are a concern in areas like Indonesia (an emerging pathogen ‘hotspot’) because of the ease with which vectors can transfer RNA viruses between wildlife, humans and livestock, and because of the large variety of pathogenic viruses already known to exist. However, there are no known records of these pathogenic viruses (such as West Nile, Sepik, Banna) in Indonesia though they are known to exist at similar latitudes. Dengue virus, present in Indonesia, is an emerging global health threat, and disease prevention depends completely on avoiding the mosquito host that transmits the virus from human to human. No other dengue disease prevention or treatment methods exist. Preliminary evidence suggests that there may be differences in allele frequencies related vector competence to transmit Dengue virus. This study seeks to understand the genetic composition of mosquito populations seasonally and among communities in order to predict levels of mosquito diversity and movement within and between communities, and to assess vector competence to transmit dengue viruses throughout a transmissions season. This study will make a survey of potentially pathogenic arboviruses from mosquitoes collected throughout Indonesia aimed at identifying viruses, their vectors, as well as temporal transmission characteristics towards discovery and informing intervention programs.
The primary objective of this proposal is to survey for potentially pathogenic mosquito-borne arboviruses in their vectors to geographically map risk, estimate force of infection, and identify potential emerging pandemic threats. A secondary objective focusing on the dengue virus vector will investigate if there is a temporal change in the vector genotype with associated impacts on vector competence between the wet and dry seasons.
This study will entail systematic collections of mosquitoes in all ecological zones prevalent on the island of Sulawesi. The study team will identify vectors to species to determine the diversity of mosquitoes and ID those known to harbor human pathogens. The researchers will also perform virus isolation in vertebrate cell cultures towards virus identification. Finally, the researchers will examine seasonal effects on Ae. aegypti population genetics and DENV susceptibility.
Public Health Impact:
It is expeced that the study team will collect circulating viruses that have never been recorded at these sites and the possibility exists of identifying novel viruses in the preliminary survey. Vector results will enable the characterization of geographic vector-virus transmission systems and will allow a better understanding of local dengue transmission and hence better intervention strategies.
Dr. Severson has an exceptional historical record of both Dengue and vector research and his expertise will be indispensable for the the critical vector studies.