Porciani Angélique, Diop Malal, Moiroux Nicolas, Kadoke-Lambi Tatiana, Cohuet Anna, Chandre Fabrice, Dormont Laurent, Pennetier Cédric
MiVEGEC (UM1-UM2-CNRS 5290-IRD 224), Institut de Recherche pour le Développement (IRD) Cotonou, Bénin.
Centre de Recherche Entomologique de Cotonou (CREC), Cotonou, Bénin.
PLoS One. 2017 Jul 31;12(7):e0164518. doi: 10.1371/journal.pone.0164518. eCollection 2017.
The use of long lasting insecticide nets (LLINs) treated with pyrethroïd is known for its major contribution in malaria control. However, LLINs are suspected to induce behavioral changes in malaria vectors, which may in turn drastically affect their efficacy against Plasmodium sp. transmission. In sub Saharan Africa, where malaria imposes the heaviest burden, the main malaria vectors are widely resistant to pyrethroïds, the insecticide family used on LLINs, which also threatens LLIN efficiency. There is therefore a crucial need for deciphering how insecticide-impregnated materials might affect the host-seeking behavior of malaria vectors in regards to insecticide resistance. In this study, we explored the impact of permethrin-impregnated net on the host attractiveness for Anopheles gambiae mosquitoes, either susceptible to insecticides, or carrying the insecticide resistance conferring allele kdr. Groups of female mosquitoes were released in a dual-choice olfactometer and their movements towards an attractive odor source (a rabbit) protected by insecticide-treated (ITN) or untreated nets (UTN) were monitored. Kdr homozygous mosquitoes, resistant to insecticides, were more attracted by a host behind an ITN than an UTN, while the presence of insecticide on the net did not affect the choice of susceptible mosquitoes. These results suggest that permethrin-impregnated net is detectable by malaria vectors and that the kdr mutation impacts their response to a LLIN protected host. We discuss the implication of these results for malaria vector control.
使用经拟除虫菊酯处理的长效驱虫蚊帐（LLINs）在疟疾防控方面的重大贡献广为人知。然而，人们怀疑LLINs会引起疟疾病媒的行为变化，这反过来可能会极大地影响其对疟原虫传播的防治效果。在疟疾负担最重的撒哈拉以南非洲地区，主要的疟疾病媒对LLINs所用的拟除虫菊酯类杀虫剂具有广泛抗性，这也威胁到了LLINs的有效性。因此，迫切需要弄清楚浸渍杀虫剂的材料在杀虫剂抗性方面如何影响疟疾病媒寻找宿主的行为。在本研究中，我们探究了浸渍氯菊酯的蚊帐对冈比亚按蚊宿主吸引力的影响，这些蚊子要么对杀虫剂敏感，要么携带赋予杀虫剂抗性的等位基因kdr。将雌蚊群体放入双选嗅觉仪中，并监测它们朝着由经杀虫剂处理的蚊帐（ITN）或未处理的蚊帐（UTN）保护的有吸引力的气味源（一只兔子）移动的情况。对杀虫剂具有抗性的kdr纯合子蚊子被ITN后面的宿主吸引的程度高于UTN后面的宿主，而蚊帐上是否存在杀虫剂并不影响敏感蚊子的选择。这些结果表明，疟疾媒介能够检测到浸渍氯菊酯的蚊帐，并且kdr突变会影响它们对LLIN保护的宿主的反应。我们讨论了这些结果对疟疾媒介控制的意义。
