@article{fdi:010066265,
  title = {{W}hen intensity of deltamethrin resistance in {A}nopheles gambiae s.l. leads to loss of {L}ong {L}asting {I}nsecticidal {N}ets bio-efficacy : a case study in north {C}ameroon},
  author = {{E}tang, {J}. and {P}ennetier, {C}{\'e}dric and {P}iameu, {M}. and {B}ouraima, {A}. and {C}handre, {F}abrice and {A}wono-{A}mbene, {P}. and {M}arc, {C}. and {C}orbel, {V}incent},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground: {I}n {C}ameroon, insecticide resistance in {A}nopheles ({A}n.) gambiae s.l. has been reported in several foci, prompting further investigations on associated patterns of {L}ong-{L}asting {I}nsecticidal {N}ets ({LLIN}s) bio-efficacy. {T}he current study, conducted from {J}une to {A}ugust 2011, explored the intensity of deltamethrin resistance in {A}n. gambiae s.l. from {P}itoa and its impact on the residual bio-efficacy of {L}ife{N}et, a {LLIN} with deltamethrin incorporated into polypropylene nets ({PND}). {M}ethods: {T}wo-four days old females {A}n. gambiae s.l. reared from larval collections in {P}itoa were tested for susceptibility to {DDT}, permethrin and deltamethrin, using standard {W}orld {H}ealth {O}rganization ({WHO}) tube assays. {I}ntensity of deltamethrin resistance was explored using {WHO} tube assays, but across six working concentrations from 0.001 % to 0.5 %. {B}io-efficacy of unwashed and washed {PND} was assessed using {WHO} cone test. {S}pecies identification and kdr 1014 genotyping were performed on mosquito samples that were not exposed to insecticides, using {PCR}-{RFLP} and {HOLA} methods respectively. {T}he {K}isumu reference susceptible strain of {A}n. gambiae s.s. was used for comparisons. {R}esults: {A} total of 1895 {A}n. gambiae s.l. specimens from {P}itoa were used for resistance and {PND} bio-efficacy testing. {T}his mosquito population was resistant to {DDT}, permethrin and deltamethrin, with 18-40 min knockdown times for 50 % of tested mosquitoes and 59-77 % mortality. {D}eltamethrin {R}esistance {R}atio compared with the {K}isumu strain was estimated at >= 500 fold. {L}ife{N}ets were effective against the susceptible {K}isumu (100 % knockdown ({KD}60min) and mortality) and the resistant {P}itoa samples (95 % {KD}60min, 83-95 % mortality). {H}owever, the bio-efficacy gradually dropped against the {P}itoa samples when nets were washed ({X}-2 = 35.887, df = 8, p < 0.001), and fell under the {WHO} efficacy threshold (80 % mortality and/or 95 % {KD}60min) between 10 and 15 washes. {T}he {P}itoa samples were composed of three sibling species: {A}n. arabiensis (132/154, 86 %), {A}n. coluzzii (19/154, 12 %) and {A}n. gambiae s.s. (3/154, 2 %). {T}he kdr {L}1014{F} allele was found only in {A}n. coluzzii ({N}-positive = 13/19), at 34 % frequency and heterozygote stage. {N}o specimen carried the kdr {L}1014{S} allele. {C}onclusions: {T}he current study showed that {L}ife{N}et might still offer some protection against the resistant {A}n. gambiae s.l. population from {P}itoa, provided appropriate dose of insecticide is available on the nets.},
  keywords = {{D}eltamethrin ; {A}nopheles gambiae s.l ; {M}alaria ; {R}esistance intensity ; {L}ong-{L}asting {I}nsecticidal {N}ets ; {V}ector control ; {CAMEROUN}},
  booktitle = {},
  journal = {{P}arasites and {V}ectors},
  volume = {9},
  numero = {},
  pages = {art. 132 [ p.]},
  ISSN = {1756-3305},
  year = {2016},
  DOI = {10.1186/s13071-016-1420-x},
  URL = {https://www.documentation.ird.fr/hor/fdi:010066265},
}