Introduction and Objectives Pyrethroid resistance (PR) of Anopheles mosquitoes is threatening the effectiveness of pyrethroidtreated bednets (ITNs), a crucial tool for malaria vector control. Pyrethroids target the voltage-gated sodium channel (VGSC) and genotyping of mutations in the VGSC gene is widely used to assess the spread of target-site resistance among malaria vectors. L1014F and L1014S substitutions are the commonest and best characterized VGSC-mutations in African malaria vectors of the Anopheles gambiae complex. Recently, a substitution involved in PR, V402L, has been detected in west-African Anopheles coluzzii. We here monitored the temporal dynamic of target-site resistance mutations L1014F/S and V402L in A. coluzzii and A. arabiensis specimens from a Burkina Faso village over 10 years after the massive ITN scale-up started in 2010. Material and Methods Anopheles coluzzii (N= 300) and A. arabiensis (N=362) specimens, collected in 2011, 2015 and 2020 in Goden village were genotyped for the three target-site resistance mutations by TaqMan-assays and sequencing. Results, Discussion and Conclusion Over the study period, 1014F-frequency decreased in A. coluzzii (from 0.76 to 0.52) but increased in A. arabiensis (from 0.18 to 0.70); 1014S was detected only in A. arabiensis (from 0.33 to 0.23); 402L increased in A. coluzzii (from 0.15 to 0.48) and was found for the first time in A. arabiensis. In 2020 resistance alleles co-occured in 43% of A. coluzzii (410L and 1014F) and 32% of A. arabiensis (1014F and 1014S). After 10 years from first ITN implementation in Goden, a significantly increasing level of target-site resistance was observed in the vector population, with only 1% of specimens being wildtype at both loci. This, together with the evidence of co-occurrence of different mutations in the same specimens, calls for future investigations on the possible synergism between resistance alleles and their phenotypic effects to implement locally tailored vector-control strategies.
Longitudinal survey of insecticide resistance in a Burkina Faso village reveals co-occurrence of 1014F/S and 402L mutations in Anopheles coluzzii and Anopheles arabiensis / Perugini, Eleonora; Pichler, Verena; Guelbeogo, Wamdaogo M.; Micocci, Martina; Poggi, Cristiana; DI MAIO, Francesca; Manzi, Sara; Ranson, Hilary; DELLA TORRE, Alessandra; Mancini, Emiliano; Pombi, Marco. - (2024), pp. -145. (Intervento presentato al convegno ONE HEALTH IN ACTION: supporting and accelerating the bridging of the vertebrate and plant health communities tenutosi a Montpellier, France).
Longitudinal survey of insecticide resistance in a Burkina Faso village reveals co-occurrence of 1014F/S and 402L mutations in Anopheles coluzzii and Anopheles arabiensis
Eleonora PERUGINI;Verena PICHLER;Wamdaogo M. GUELBEOGO;Martina MICOCCI;Cristiana POGGI;Sara MANZI;Alessandra DELLA TORRE;Emiliano MANCINI;Marco POMBI
2024
Abstract
Introduction and Objectives Pyrethroid resistance (PR) of Anopheles mosquitoes is threatening the effectiveness of pyrethroidtreated bednets (ITNs), a crucial tool for malaria vector control. Pyrethroids target the voltage-gated sodium channel (VGSC) and genotyping of mutations in the VGSC gene is widely used to assess the spread of target-site resistance among malaria vectors. L1014F and L1014S substitutions are the commonest and best characterized VGSC-mutations in African malaria vectors of the Anopheles gambiae complex. Recently, a substitution involved in PR, V402L, has been detected in west-African Anopheles coluzzii. We here monitored the temporal dynamic of target-site resistance mutations L1014F/S and V402L in A. coluzzii and A. arabiensis specimens from a Burkina Faso village over 10 years after the massive ITN scale-up started in 2010. Material and Methods Anopheles coluzzii (N= 300) and A. arabiensis (N=362) specimens, collected in 2011, 2015 and 2020 in Goden village were genotyped for the three target-site resistance mutations by TaqMan-assays and sequencing. Results, Discussion and Conclusion Over the study period, 1014F-frequency decreased in A. coluzzii (from 0.76 to 0.52) but increased in A. arabiensis (from 0.18 to 0.70); 1014S was detected only in A. arabiensis (from 0.33 to 0.23); 402L increased in A. coluzzii (from 0.15 to 0.48) and was found for the first time in A. arabiensis. In 2020 resistance alleles co-occured in 43% of A. coluzzii (410L and 1014F) and 32% of A. arabiensis (1014F and 1014S). After 10 years from first ITN implementation in Goden, a significantly increasing level of target-site resistance was observed in the vector population, with only 1% of specimens being wildtype at both loci. This, together with the evidence of co-occurrence of different mutations in the same specimens, calls for future investigations on the possible synergism between resistance alleles and their phenotypic effects to implement locally tailored vector-control strategies.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
