Ibrahim Sulaiman S, Manu Yayo A, Tukur Zainab, Irving Helen, Wondji Charles S
Bayero University, P,M,B, 3011, Kano, Nigeria.
BMC Infect Dis. 2014 Aug 15;14:441. doi: 10.1186/1471-2334-14-441.
Malaria burden is high in Nigeria, yet information on the major mosquito vectors is lacking especially in the Sudan savannah region of the country. In order to facilitate the design of future insecticide-based control interventions in the region, this study has established the resistance profile of An. gambiae s.l. populations in two northern Nigeria locations and assessed the contribution of target site resistance mutations.
Larval collection was conducted in two localities in Sudan savannah (Bunkure and Auyo) of northern Nigeria between 2009 and 2011, from which resulting adult, female mosquitoes were used for insecticides bioassays with deltamethrin, lambda-cyhalothrin, DDT and malathion. The mosquitoes were identified to species level and molecular forms and then genotyped for the presence of L1014F-kdr, L1014S-kdr and ace-1R mutations.
WHO bioassays revealed that An. gambiae s.l. from both localities were highly resistant to lambda-cyhalothrin and DDT, but only moderately resistant to deltamethrin. Full susceptibility was observed to malathion. An. gambiae, M form (now An. coluzzii), was predominant over An. arabiensis in Auyo and was more resistant to lambda-cyhalothrin than An. arabiensis. No 'S' form (An. gambiae s.s.) was detected. A high frequency of 1014 F mutation (80.1%) was found in An. coluzzii in contrast to An. arabiensis (13.5%). The presence of the 1014 F kdr allele was significantly associated with resistance to lambda-cyhalothrin in An. coluzzii (OR = 9.85; P < 0.001) but not in An. arabiensis. The L1014S-kdr mutation was detected in a single An. arabiensis mosquito while no ace-1R mutation was found in any of the mosquitoes analysed.
The predominance of An. coluzzii and its resistance profile to main insecticides described in this study can guide the implementation of appropriate vector control interventions in this region of Nigeria where such information was previously lacking.
尼日利亚疟疾负担沉重，但缺乏关于主要蚊媒的信息，尤其是在该国的苏丹草原地区。为了便于在该地区设计未来基于杀虫剂的控制干预措施，本研究确定了尼日利亚北部两个地点冈比亚按蚊复合种群的抗性概况，并评估了靶标位点抗性突变的作用。
2009年至2011年期间，在尼日利亚北部苏丹草原的两个地点（邦库雷和奥约）进行幼虫采集，从采集的幼虫羽化出的成年雌性蚊子用于进行溴氰菊酯、高效氯氟氰菊酯、滴滴涕和马拉硫磷的杀虫剂生物测定。将蚊子鉴定到物种水平和分子型，然后对其进行基因分型，以检测是否存在L1014F-kdr、L1014S-kdr和ace-1R突变。
世卫组织生物测定显示，来自两个地点的冈比亚按蚊复合种群对高效氯氟氰菊酯和滴滴涕高度耐药，但对溴氰菊酯仅中度耐药。观察到对马拉硫磷完全敏感。在奥约，冈比亚按蚊M型（现为科氏按蚊）比阿拉伯按蚊更为常见，且对高效氯氟氰菊酯的耐药性比阿拉伯按蚊更强。未检测到“S”型（冈比亚按蚊指名亚种）。与阿拉伯按蚊（13.5%）相比，在科氏按蚊中发现1014F突变的频率很高（80.1%）。1014F kdr等位基因的存在与科氏按蚊对高效氯氟氰菊酯的耐药性显著相关（比值比=9.85；P<0.001），但与阿拉伯按蚊无关。在一只阿拉伯按蚊中检测到L1014S-kdr突变，而在所分析的任何蚊子中均未发现ace-1R突变。
本研究中描述的科氏按蚊的优势及其对主要杀虫剂的抗性概况，可以指导在尼日利亚这一此前缺乏此类信息的地区实施适当的媒介控制干预措施。
Zotero 插件
