Outdoor Residual Insecticide Spraying (ODRS), a New Approach for the Control of the Exophilic Vectors of Human Visceral Leishmaniasis: Phlebotomus orientalis in East Africa.
Outdoor Residual Insecticide Spraying (ODRS), a New Approach for the Control of the Exophilic Vectors of Human Visceral Leishmaniasis: Phlebotomus orientalis in East Africa.
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DOI：
10.1371/journal.pntd.0008774
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发表时间：
2020-10
影响因子：
3.8
通讯作者：
Courtenay O
中科院分区：
文献类型：
--
作者：
Elnaiem DA;Dakein O;Alawad AM;Alsharif B;Khogali A;Jibreel T;Osman OF;Has'san H;Atia AM;Elhag M;Den Boer M;Ritmeijer K;Bern C;Alvar J;Khalid N;Courtenay O
由杜氏利什曼原虫引起的内脏利什曼病 (VL) 是一种被忽视的人类原虫寄生虫病，如果不治疗通常是致命的。东方白蛉是东非主要的 VL 媒介，是一种高度嗜外性/外食性的物种，对当前媒介综合管理 (IVM) 提出了重大挑战。在这里，我们报告了在苏丹盖达里夫州乡村进行的试点研究的结果，以评估将 20 毫克活性成分 (a.i)/m2 溴氰菊酯杀虫剂户外滞留喷洒在典型的家庭复合边界芦苇围栏和家庭建筑物外部（室外残留杀虫剂喷雾，ODRS），以及作为替代方案，仅喷洒在边界围栏上（限制室外残留杀虫剂喷雾，罗德斯）。在三项实验中，四到六个小组（每组 20 户）被分配进行杀虫剂治疗或控制。相对于未喷洒农药的对照组，在 43-76 天的跟踪时间内，对每个集群的四个哨点房屋进行了 2,033 个诱捕夜的白蛉数量变化监测。通过放置在边界围栏内部（“室外”）和外部（“家庭周围”）地面上的粘性陷阱以及悬挂在家庭院落户外的 CDC 光陷阱来监测沙蝇数量。通过杀虫剂抑制来监测 ODRS 对睡眠小屋内沙蝇数量的影响。单次施用后，ODRS 将室外和家庭周围陷阱位置的侧柏丰度降低了 83%-99%。 ODRS 还减少了睡在小屋内的侧柏数量。 RODRS 使室外和家庭周围的侧柏减少了 60%-88%。通过直接比较，根据捕获方法的不同，RODRS 的效果与 ODRS 的效果相同，为 58%-100%。这些影响在干预时立即产生，并在后续过程中持续存在，占侧柏活动季节的很大一部分。每户 ODRS 和 RODRS 交付的相对成本分别为 5.76 美元和 3.48 美元。该研究证明了 ODRS 和 RODRS 的可行性和高昆虫学功效，以及相对于当前 IVM 实践的预期低成本。这些方法代表了针对主要是外食性/外食性白蛉媒介的新型白蛉媒介控制工具，旨在降低苏丹的VL负担，并有可能在东非其他流行地区得到应用。东方白蛉是苏丹和东非其他国家内脏利什曼病（VL、黑热病）的主要传播媒介，该病在这些国家导致高发病率和死亡率。这种森林白蛉物种在野生栖息地中大量存在，其特征是存在黑色棉花土壤和以埃及蕉和/或金合欢树为主的植被。在村庄里，病媒会叮咬家庭院子和附近家庭附近的人们，表现出有限的室内休息行为。侧柏明显的外食性和嗜外性行为对 VL 控制提出了深刻的挑战，因为排除了室内滞留喷洒杀虫剂 (IRS) 并损害了杀虫剂浸渍蚊帐 (ITN) 的功效。在本研究中，我们评估了在室外家庭边界围栏和家庭小屋外墙上施用残留拟除虫菊酯（室外残留杀虫剂喷洒，ODRS）以减少房屋内外侧柏丰度的昆虫学功效。我们还评估了限制性室外残留杀虫剂喷洒（RODRS）的昆虫学影响，其中杀虫剂仅喷洒在边界围栏上。该研究于 2016 年 6 月至 2017 年 6 月在苏丹东部盖达里夫州 Jebel-Algana 和 Umsalala 村庄进行，这些村庄是 VL 高度流行的地区。结果表明，单次 ODRS 应用 20mg a.i.相对于未喷洒的对照群，每平方米 2.8% 溴氰菊酯使室外和家庭周围的侧柏白蛉数量平均减少 83%-99%。 RODRS 使室外和家庭周围的侧柏减少了 60%-88%。每户 ODRS 和 RODRS 的平均成本分别为 5.76 美元和 3.48 美元。这些基于社区的控制措施的成本大大低于 LLIN 的成本，LLIN 是该地区用于预防 VL 的唯一基于证据的工具。未来的研究应评估 ODRS/RODRS 传播对流行村庄和季节性农业农场中 VL 发病率的影响。
Visceral Leishmaniasis (VL) due to Leishmania donovani is a neglected protozoan parasitic disease in humans, which is usually fatal if untreated. Phlebotomus orientalis, the predominant VL vector in East Africa, is a highly exophilic/exophagic species that poses a major challenge to current Integrated Vector Management (IVM). Here we report results of pilot studies conducted in rural villages in Gedarif state, Sudan, to evaluate outdoor residual spraying of 20mg active ingredient (a.i.) /m2 deltamethrin insecticide applied to the characteristic household compound boundary reed fence and to the outside of household buildings (Outdoor Residual Insecticide Spraying, ODRS), and as an alternative, spraying restricted to the boundary fence only (Restricted Outdoor Residual Insecticide Spraying, RODRS). Four to six clusters of 20 households were assigned to insecticide treatments or control in three experiments. Changes in sand fly numbers were monitored over 2,033 trap-nights over 43–76 days follow-up in four sentinel houses per cluster relative to unsprayed control clusters. Sand fly numbers were monitored by sticky traps placed on the ground on the inside (“outdoor”) and the outside (“peridomestic”) of the boundary fence, and by CDC light traps suspended outdoors in the household compound. The effects of ODRS on sand fly numbers inside sleeping huts were monitored by insecticide knockdown. After a single application, ODRS reduced P. orientalis abundance by 83%-99% in outdoor and peridomestic trap locations. ODRS also reduced numbers of P. orientalis found resting inside sleeping huts. RODRS reduced outdoor and peridomestic P. orientalis by 60%-88%. By direct comparison, RODRS was 58%-100% as effective as ODRS depending on the trapping method. These impacts were immediate on intervention and persisted during follow-up, representing a large fraction of the P. orientalis activity season. Relative costs of ODRS and RODRS delivery were $5.76 and $3.48 per household, respectively. The study demonstrates the feasibility and high entomological efficacy of ODRS and RODRS, and the expected low costs relative to current IVM practises. These methods represent novel sand fly vector control tools against predominantly exophilic/exophagic sand fly vectors, aimed to lower VL burdens in Sudan, with potential application in other endemic regions in East Africa. Phlebotomus orientalis is the predominant vector of visceral leishmaniasis (VL, kala azar) in Sudan and other countries of East Africa, where the disease causes high morbidity and mortality. This sylvatic sand fly species is abundant in wild habitats characterized by presence of black cotton soil and vegetation dominated by Balanites aegyptiaca and/or Acacia seyal trees. In villages, the vector bites people in the household yard and in nearby peri-domestic locations, exhibiting limited indoor resting behaviour. The marked exophagic and exophilic behaviours of P. orientalis represent a profound challenge for VL control by excluding indoor residual spraying of insecticides (IRS) and compromising the efficacy of insecticide-impregnated bednets (ITNs). In this study, we evaluated the entomological efficacy of residual pyrethroid applied outdoors to household boundary fences and the exterior walls of household huts (outdoor residual insecticide spraying, ODRS), to reduce the abundance of P. orientalis inside and outside houses. We also evaluated the entomological impact of a restricted outdoor residual insecticide spraying (RODRS), whereby insecticide was applied only to the boundary fence. The study was carried out in June 2016-June 2017 in Jebel-Algana and Umsalala villages, Gedarif state, eastern Sudan, which are highly endemic for VL. The results showed that a single ODRS application of 20mg a.i. /m2 2.8% deltamethrin provided average reductions of 83%-99% in outdoor and peridomestic P. orientalis sand fly numbers relative to unsprayed control clusters. RODRS reduced outdoor and peridomestic P. orientalis by 60%-88%. The average cost of ODRS and RODRS per household were $5.76 and $3.48, respectively. The costs of these community-based control measures were substantially lower than the costs of LLINs, which is the only evidence-based tool used to protect against VL in the area. Future studies should evaluate the impact of ODRS/RODRS transmission of VL incidence in endemic villages and in seasonal agricultural farms.
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影响因子：
3.8
作者：
Abubakar A;Ruiz-Postigo JA;Pita J;Lado M;Ben-Ismail R;Argaw D;Alvar J
通讯作者：
Alvar J
影响因子：
3.7
作者：
Aklilu E;Gebresilassie A;Yared S;Kindu M;Tekie H;Balkew M;Warburg A;Hailu A;Gebre-Michael T
通讯作者：
Gebre-Michael T
影响因子：
--
作者：
Elnaiem, DA;Hassan, HK;Ward, RD
通讯作者：
Ward, RD
影响因子：
2.7
作者：
Hassan, MM;Elraba'a, FMA;Elnaiem, DA
通讯作者：
Elnaiem, DA
影响因子：
8.4
作者：
Adama, Gamal K.;Ali, Khalid M.;Ali, AbdelAziem A.
通讯作者：
Ali, AbdelAziem A.