The 13th of December 2024 sparked a new path for the recently awarded Dr. Djounkwa Nouage Lynda at the Faculty of Science of the University of Yaoundé I, Cameroon.
Lynda Nouage obtained the highest distinction
Her study was placed under the theme: “Impact of insecticide resistance on salivary proteins composition (sialome) and its effect on vectoral capacity Anopheles funestus, main malaria vectors in Cameroon”. During her course, she worked under a supervision team composed of Pr. Charles Wondji, Dr. Emmanuel Elanga N’Dille and Pr. Sévilor Kekeunou. The thesis investigated how the changes in salivary gland content caused by insecticide resistance may impact Anopheles funestus mosquito blood meal intake and its ability to transmit parasites to humans. Data generated revealed that insecticide resistance alters the expression of salivary glands proteins in these mosquitoes. The results from these experiments suggest that the cytochrome genes family mediated pyrethroid resistance increases both the likelihood of mosquito to blood feed and the size of the blood meal in mosquitoes, whereas the glutathione genes mediated resistance had no effect. However, the impact of the modulation of salivary proteins by insecticide resistance on the mosquito’s ability to harbour sporozoites in the salivary glands remains unclear, largely due to the absence of homozygous resistant individuals with positive sporozoites counts.
Dr Djounkwa with her supervisory team
The method used consisted in collecting adult mosquitoes to select different strains after which their salivary glands were dissected, nucleic acids extracted and sequenced. The candidate also took advantage of the availability of molecular markers, such as L119F-GSTe2 and CYP6P9a/ b, to assess their impact on the blood meal intake and parasite transmission. The adult mosquitoes were used to quantify the size of the blood meal and for experimental infections with Plasmodium falciparum gametocyte-positive blood. At the public health policy level, this study provides data on malaria vector control in Cameroon by assessing the impact of insecticide resistance on the salivary protein composition of Anopheles funestus, their blood meal intake and the invasion of their salivary glands by Plasmodium sporozoites. These findings should lead to strategies to enhance public health outcome based on integrated resistance management, including genetic interventions targeting specific salivary genes.
All the best, Dr. Djounkwa!
