Association of 410L, 1016I and 1534C kdr mutations with pyrethroid resistance in Aedes aegypti from Ouagadougou, Burkina Faso, and development of a one-step multiplex PCR method for the simultaneous detection of 1534C and 1016I kdr mutations

<jats:title>Abstract</jats:title> <jats:p><jats:bold>Background</jats:bold>: Since 2000, Burkina Faso has experienced regular dengue cases and outbreaks making dengue a health concern for the country. Previous studies in Burkina Faso reported the resistance of <jats:italic>Aedes aegypti</jats:italic> to pyrethroid insecticides associated with F1534C and V1016I <jats:italic>kdr</jats:italic> mutations. The current study reports high resistance of <jats:italic>Ae. aegypti</jats:italic> populations to pyrethroid insecticides supported by 410L/1016I/1534C kdr haplotypes; and a new multiplex PCR-based diagnostic of 1534C and 1016I kdr mutations is proposed<jats:italic>. </jats:italic><jats:bold>Method</jats:bold>s: Larvae of <jats:italic>Ae. aegypti</jats:italic> were collected from three health districts of Ouagadougou in 2018. The resistance status of <jats:italic>Ae. aegypti</jats:italic> to pyrethroid insecticides was tested using CDC-bottle bioassays, and to malathion using WHO tube tests. Bioassay results were interpreted according to used protocols. <jats:bold>Results</jats:bold><jats:italic>: </jats:italic>Females from each health district were strongly resistant to permethrin and deltamethrin (<20% mortality) but were fully susceptible to 5% malathion. The F1534C and V1016I <jats:italic>kdr</jats:italic> mutations were successfully detected using a newly-developed multiplex PCR, which was validated by comparison with fluorescent probe-based TaqMan assays for each mutation. The V410L<jats:italic> kdr</jats:italic> mutation was detected using an allele-specific-PCR, which was confirmed by TaqMan assays, and owing to novelty in local <jats:italic>Ae. aegypti</jats:italic> populations, also direct DNA sequencing. The 1534C <jats:italic>kdr</jats:italic> allele was near fixation, while V1016I and V410L<jats:italic> kdr</jats:italic> alleles were strongly correlated with allelic frequencies range from 0.5 to 0.7 across the three-health districts. The 1534C/1016I/410L haplotype was correlated with permethrin resistance (<jats:italic>χ</jats:italic><jats:sup><jats:italic>2</jats:italic></jats:sup><jats:sub><jats:italic>1</jats:italic></jats:sub>=33.7; <jats:italic>p</jats:italic><0.001) but not with deltamethrin resistance (<jats:italic>χ</jats:italic><jats:sup><jats:italic>2</jats:italic></jats:sup><jats:sub><jats:italic>1</jats:italic></jats:sub>=0.03; <jats:italic>p</jats:italic>=0.86), however, the test power was limited by a low frequency of dead individuals. <jats:bold>Conclusions<jats:italic>:</jats:italic></jats:bold><jats:italic> </jats:italic>The<jats:italic> </jats:italic>trio of <jats:italic>kdr</jats:italic> mutations (F1534C, V1016I and V410L) may explain the high resistance to pyrethroids, however lack of substantial resistance to malathion suggests that this remains a viable option for dengue vectors control in Ouagadougou.</jats:p>