Dengue is a viral infection caused by the dengue virus (DENV), an arbovirus responsible for nearly 400 million cases each year worldwide. As with many infections with flaviviruses, dengue is mostly asymptomatic. However, some patients may develop symptoms such as fever, vomiting, or skin rashes. In the most severe cases, a hemorrhagic form of dengue may occur, potentially leading to the patient’s death.
The virus is primarily transmitted by mosquitoes of the Aedes genus, particularly Aedes aegypti. To date, no specific antiviral treatment is available for dengue. Despite the development of vaccines with limited efficacy, vector control, which consists of reducing mosquito vector populations, notably using insecticides, remains the most effective control measure.
However, the exposure of mosquitoes to sublethal doses of insecticides can induce non-lethal physiological effects, potentially altering their vector competence. Moreover, this exposure could exert selective pressure on the viruses present in infected mosquitoes, thereby influencing the diversity of viral populations and promoting the emergence of specific mutations and variants.
In this context, Ae. aegypti mosquitoes were experimentally infected with DENV and then exposed or not to an insecticide. Mosquito saliva was collected, and the viruses present were amplified in C6/36 mosquito cells.
The objective of this project is to analyze the genetic diversity of viral populations present in the saliva of mosquitoes exposed or not to insecticide. The aim is to compare the viral sequences obtained to determine whether exposure to a sublethal dose of insecticide promotes the emergence of specific mutations. If so, we will identify their location in the viral genome and evaluate their potential impact on virus fitness and transmissibility by mosquitoes.
