Exploring the vectorial capacity of Aedes aegypti and Aedes albopictus for dengue virus in Benin: Impact of insecticide resistance and larval competition

• Applicant: Dr. Renke Lühken, since 8/2025
• Subject Area: Virology
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 380283251

Arboviruses, particularly the dengue virus (DENV), are a growing public health threat in West Africa. In 2023 and 2024, a multi-country outbreak of DENV was reported, with over 100,000 confirmed cases and 817 deaths. Despite the circulation of different DENV serotypes in the region, little is known about the local transmission dynamics. The invasive species Aedes albopictus is also expanding its range in both urban and rural areas, but the impact on local Aedes species and disease dynamics, especially for arboviruses like DENV, remains largely unknown. This project aims to explore the vectorial capacity of Aedes aegypti and Aedes albopictus for DENV in Benin, focusing on the effects of insecticide resistance, larval competition, and vector competence on transmission dynamics. By combining laboratory experiments, field studies, and predictive modeling, we will address key gaps in the understanding of DENV transmission in the region. First, we will investigate how larval competition between Ae. aegypti and Ae. albopictus affects development rates, survival, and adult body size under controlled laboratory and natural field conditions. These experiments will shed light on how competition and environmental factors shape mosquito life history traits and influence their ability to transmit DENV. Next, we will evaluate the vector competence of both mosquito species using local DENV strains isolated from patient samples in Benin. Infection experiments will measure infection rates, viral load, and the extrinsic incubation period, providing crucial insights into the relationship between DENV strains and vector species. We will also examine insecticide resistance in field populations by screening for resistance markers like kdr mutations using molecular techniques. By establishing resistant and non-resistant mosquito colonies, we will study how insecticide resistance impacts mosquito survival and DENV transmission. The combined effects of larval competition and insecticide resistance will be explored to understand their interaction and impact on the overall vectorial capacity of both species. These data will feed into a predictive model that incorporates factors such as mosquito density, biting rate, survival probability, and vector competence, allowing us to estimate how competition, resistance, and environmental changes affect disease transmission. In parallel, the project includes a strong capacity-building component focused on training young African researchers, especially women, in advanced techniques for vector-borne disease research. Research stays in Germany will help foster sustainable research capacity and long-term partnerships between African and European institutions. This integrated approach will generate new insights into DENV transmission in West Africa and support the development of improved public health strategies to combat mosquito-borne diseases.

• DFG Programme: Research Grants
• International Connection: Benin
• International Co-Applicant: Dr. Anges Yadouléton
• Ehemalige Antragstellerin: Dr. Hanna Jöst, until 8/2025