Name: Sombié Aboubacar
Affiliation: University Ouaga, Burkina Faso
Position: Ph.D student under Prof. Joseph Ki-Zerbo
Term: May 2018 to July 2018
Host researcher: Dr. Shinya Fukumoto
Circumstances of application:
Dengue cases occurred frequently in Burkina Faso since 2006. The last big dengue outbreak was in 2017 resulting in around 14500 cases and 29 deaths. This dengue outbreak has highlighted the lack of information on dengue vector required for its control. Apply NRCPD position was for me to investigate molecular mechanism of insecticide resistance within dengue vector, Aedes aegypti.
Research activity in NRCPD:
Around 500 Aedes aegypti mosquito were genotyping by allele specific PCR (AS-PCR). Direct sequencing was performed to confirm AS-PCR genotyping. Two mutations namely F1534C and V1016I involved in insecticide resistance were detected. Direct sequencing has confirmed AS-PCR genotypes for F1534C and V1016I mutations. While F1534C mutation was found at high allelic frequency (0.97), the V1016I mutation was found at moderate allelic frequency (0.46). All Aedes aegypti mosquito were mutant (93% homozygote, 1534C/C; 7% heterozygote, 1534F/C) for F1534C mutation. But for V1016I, 29% was Wild-type (1016V/V), 49% and 21% were respectively mutant heterozygote (1016V/I) and homozygote (1016I/I). It was also observed that F1534C and V1016I mutations co-occurred and six haplotypes (FV/CV, FV/CI, FI/CI, CV/CV, CV/CI and CI/CI) were noted. These two mutations were involved in permethrin-resistance (p-value was 0.027 for V1016I and 0.001 for F1534C; Fisher exact test) but not to deltamethrin-resistance (p = 0.117 for V1016I and p = 1 for F1534C; Fisher exact test). Co-occurrence of F1534C and V1016I were highest associated to permethrin-resistance (p = 0, Fisher Exact test) of Aedes aegypti.
Future prospects:
We will use these results as the baseline for the new research on Aedes aegypti that we will do. In fact, we want to make a map for resistance to insecticides of Aedes aegypti and the mechanisms (molecular and biochemical mechanisms) involving in this resistance in Burkina Faso.