BJRP 011208

SURVEILLANCE OF DENGUE VECTORS DIRECTED TO ASSESSING THE RISK OF DENV TRANSMISSION

Abstract

Over the last decades, dengue increased exponentially and has become the most important viral disease in humans transmitted by mosquitoes. Transmission among the human population occurs through the bite of an Aedes mosquito infected with any one of the four dengue virus serotypes (i.e. DENV-1, -2, -3 and -4). The disease is widespread throughout most of South-east Asia, the Pacific, the Indian subcontinent, sub-Saharan Africa, Central and South America and the Caribbean. Eighty percent of dengue cases in South America occur in Brazil. Due to increased international travel and spread of dengue-competent Aedes species across the globe, dengue is also becoming a serious threat in Europe. Reports on dengue cases imported to Europe are increasing and recently we had the first cases of dengue transmission in France and Croatia. Many factors determine DEVN transmission thresholds and the likelihood of an outbreak. The ability of the mosquito to transmit the disease (vector competence), the frequency of hot-mosquito contact and the mosquito’s susceptibility to control measures are key factors in assessing the risks for potential transmission and the role of individual mosquito species. Vector competence of Aedes population for DENVs varies widely and members of this genus often show a discontinuous distribution, with localized breeding units, due to low dispersal rates and reintroductions. In order to better understand these factors, we will evaluate the vector competence, seasonal abundance and host preference of A. aegypti and A. albopictus under the specific, local settings in Brazil and Switzerland. Our data on mosquito biology will provide the basis for assessing the risk of dengue outbreaks and help to improve surveillance and intervention in both countries.


Dr. Pie MÜLLER
Dr. Leda REGIS