METHODS: This study was conducted in the health district of Korhogo, northern Côte d\'Ivoire, within two study arms (LLIN + Bti arm and LLIN-only arm) from March 2019 to February 2020. In the LLIN + Bti arm, Anopheles larval habitats were treated every fortnight with Bti in addition to the use of LLINs. Mosquito larvae and adults were sampled and identified morphologically to genus and species using standard methods. The members of the An. gambiae complex were determined using a polymerase chain reaction technique. Plasmodium infection in An. gambiae s.l. and malaria incidence in local people was also assessed.
RESULTS: Overall, Anopheles spp. larval density was lower in the LLIN + Bti arm 0.61 [95% CI 0.41-0.81] larva/dip (l/dip) compared with the LLIN-only arm 3.97 [95% CI 3.56-4.38] l/dip (RR = 6.50; 95% CI 5.81-7.29; P < 0.001). The overall biting rate of An. gambiae s.l. was 0.59 [95% CI 0.43-0.75] biting/person/night in the LLIN + Bti arm against 2.97 [95% CI 2.02-3.93] biting/person/night in LLIN-only arm (P < 0.001). Anopheles gambiae s.l. was predominantly identified as An. gambiae sensu stricto (s.s.) (95.1%, n = 293), followed by Anopheles coluzzii (4.9%; n = 15). The human-blood index was 80.5% (n = 389) in study area. EIR was 1.36 infected bites/person/year (ib/p/y) in the LLIN + Bti arm against 47.71 ib/p/y in the LLIN-only arm. Malaria incidence dramatically declined from 291.8‰ (n = 765) to 111.4‰ (n = 292) in LLIN + Bti arm (P < 0.001).
CONCLUSIONS: The combined use of LLINs with Bti significantly reduced the incidence of malaria. The LLINs and Bti duo could be a promising integrated approach for effective vector control of An. gambiae for elimination of malaria.
方法:这项研究是在科霍戈的卫生区进行的,科特迪瓦北部,从2019年3月到2020年2月,在两个研究组(LLIN+Bti臂和LLIN-only臂)内。在LLIN+Bti臂中,除使用LLINs外,每两周用Bti处理按蚊幼虫栖息地。对蚊子幼虫和成虫进行采样,并使用标准方法在形态上对其属和种进行鉴定。An的成员。使用聚合酶链反应技术确定冈比亚复合物。An中的疟原虫感染。冈比亚s.l.和当地人民的疟疾发病率也被评估。
结果:总体而言,按蚊。与仅LLIN臂3.97[95%CI3.56-4.38]l/dip相比,LLINBti臂的幼虫密度较低0.61[95%CI0.41-0.81]幼虫/dip(l/dip)(RR=6.50;95%CI5.81-7.29;P<0.001)。An的整体咬率。冈比亚s.l.LLIN+Bti臂咬伤/人/晚0.59[95%CI0.43-0.75],仅LLIN臂咬伤/人/晚2.97[95%CI2.02-3.93](P<0.001)。冈比亚按蚊主要被鉴定为An。冈比亚严格意义(s.s.)(95.1%,n=293),其次是结肠按蚊(4.9%;n=15)。研究区域的人体血液指数为80.5%(n=389)。在LLINBti组中,EIR为1.36感染叮咬/人/年(ib/p/y),而在仅LLIN组中为47.71ib/p/y。LLINBti组的疟疾发病率从291.8‰(n=765)下降到111.4‰(n=292)(P<0.001)。
结论:LLINs与Bti的联合使用显着降低了疟疾的发病率。LLINs和Bti二人组可能是有效控制An的一种有前途的综合方法。冈比亚消除疟疾。