TY - JOUR
T1 - Exploring insecticide resistance mechanisms in three major malaria vectors from Bangui in Central African Republic
AU - Kamgang, Basile
AU - Tchapga, Williams
AU - Ngoagouni, Carine
AU - Sangbakembi-Ngounou, Claire
AU - Wondji, Murielle
AU - Riveron, Jacob M.
AU - Wondji, Charles
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Malaria remains the main cause of mortality and morbidity in the Central African Republic. However, the main malaria vectors remain poorly characterised, preventing the design of suitable control strategies. Here, we characterised the patterns and mechanisms of insecticide resistance in three important vectors from Bangui.Mosquitoes were collected indoors, using electrical aspirators in July 2016 in two neighborhoods at Bangui. WHO bioassays performed, using F2 An. gambiae sensu lato (s.l.), revealed a high level of resistance to type I (permethrin) and II (deltamethrin) pyrethroids and dichlorodiphenyltrichloroethane (< 3% mortality). Molecular analysis revealed the co-occurrence of Anopheles coluzzii (56.8 %) and An. gambiae s.s. (43.2%) within the An. gambiae complex. Anopheles funestus s.s. was the sole species belonging to An. funestus group. Both kdr-w (40% of homozygotes and 60% of heterozygotes/kdr-w/wild type) and kdr-e (37.5% of heterozygotes) mutations were found in An. gambiae. Contrariwise, only the kdr-w (9.5% homozygotes and 85.7% of heterozygotes) was detected in An. coluzzii. Quantitative RT-PCR showed that CYP6M2 and CYP6P3 are not upregulated in An. coluzzii from Bangui. Analysis of the sodium channel gene revealed a reduced diversity in An. coluzzii and An. gambiae s.s. In An. funestus s.s., the pyrethroid/DDT GSTe2 L119F resistance allele was detected at high frequency (54.7%) whereas a very low frequency for Rdl was observed. Polymorphism analysis of GSTe2 and GABA receptor gene in An. funestus revealed the presence of one resistant haplotype for each gene.This study provides baseline information to help guide current and future malaria vector control interventions in CAR.
AB - Malaria remains the main cause of mortality and morbidity in the Central African Republic. However, the main malaria vectors remain poorly characterised, preventing the design of suitable control strategies. Here, we characterised the patterns and mechanisms of insecticide resistance in three important vectors from Bangui.Mosquitoes were collected indoors, using electrical aspirators in July 2016 in two neighborhoods at Bangui. WHO bioassays performed, using F2 An. gambiae sensu lato (s.l.), revealed a high level of resistance to type I (permethrin) and II (deltamethrin) pyrethroids and dichlorodiphenyltrichloroethane (< 3% mortality). Molecular analysis revealed the co-occurrence of Anopheles coluzzii (56.8 %) and An. gambiae s.s. (43.2%) within the An. gambiae complex. Anopheles funestus s.s. was the sole species belonging to An. funestus group. Both kdr-w (40% of homozygotes and 60% of heterozygotes/kdr-w/wild type) and kdr-e (37.5% of heterozygotes) mutations were found in An. gambiae. Contrariwise, only the kdr-w (9.5% homozygotes and 85.7% of heterozygotes) was detected in An. coluzzii. Quantitative RT-PCR showed that CYP6M2 and CYP6P3 are not upregulated in An. coluzzii from Bangui. Analysis of the sodium channel gene revealed a reduced diversity in An. coluzzii and An. gambiae s.s. In An. funestus s.s., the pyrethroid/DDT GSTe2 L119F resistance allele was detected at high frequency (54.7%) whereas a very low frequency for Rdl was observed. Polymorphism analysis of GSTe2 and GABA receptor gene in An. funestus revealed the presence of one resistant haplotype for each gene.This study provides baseline information to help guide current and future malaria vector control interventions in CAR.
KW - Central African Republic
KW - insecticide resistance mechanism
KW - Malaria
KW - vector
U2 - 10.1080/20477724.2018.1541160
DO - 10.1080/20477724.2018.1541160
M3 - Article
SN - 2047-7724
VL - 112
SP - 349
EP - 359
JO - Pathogens and Global Health
JF - Pathogens and Global Health
IS - 7
ER -
