U.S. President's Malaria Initiative (PMI) Abt Associates/VectorLink Project, Dakar, Senegal.
Laboratoire d'Ecologie Vectorielle et Parasitaire, Faculté Des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Sénégal.
Parasit Vectors. 2023 Sep 19;16(1):331. doi: 10.1186/s13071-023-05932-9.
Malaria is endemic in Senegal, with seasonal transmission, and the entire population is at risk. In recent years, high malaria incidence has been reported in urban and peri-urban areas of Senegal. An urban landscape analysis was conducted in three cities to identify the malaria transmission indicators and human behavior that may be driving the increasing malaria incidence occurring in urban environments. Specifically, mosquito vector bionomics and human sleeping behaviors including outdoor sleeping habits were assessed to guide the optimal deployment of targeted vector control interventions.
Longitudinal entomological monitoring using human landing catches and pyrethrum spray catches was conducted from May to December 2019 in Diourbel, Kaolack, and Touba, the most populous cities in Senegal after the capital Dakar. Additionally, a household survey was conducted in randomly selected houses and residential Koranic schools in the same cities to assess house structures, sleeping spaces, sleeping behavior, and population knowledge about malaria and vector control measures.
Of the 8240 Anopheles mosquitoes collected from all the surveyed sites, 99.4% (8,191) were An. gambiae s.l., and predominantly An. arabiensis (99%). A higher number of An. gambiae s.l. were collected in Kaolack (77.7%, n = 6496) than in Diourbel and Touba. The overall mean human biting rate was 14.2 bites per person per night (b/p/n) and was higher outdoors (15.9 b/p/n) than indoors (12.5 b/p/n). The overall mean entomological inoculation rates ranged from 3.7 infectious bites per person per year (ib/p/y) in Diourbel to 40.2 ib/p/y in Kaolack. Low anthropophilic rates were recorded at all sites (average 35.7%). Of the 1202 households surveyed, about 24.3% of household members slept outdoors, except during the short rainy season between July and October, despite understanding how malaria is transmitted and the vector control measures used to prevent it.
Anopheles arabiensis was the primary malaria vector in the three surveyed cities. The species showed an outdoor biting tendency, which represents a risk for the large proportion of the population sleeping outdoors. As all current vector control measures implemented in the country target endophilic vectors, these data highlight potential gaps in population protection and call for complementary tools and approaches targeting outdoor biting malaria vectors.
塞内加尔存在地方性疟疾，且呈季节性传播，因此全体居民都有感染风险。近年来，塞内加尔城市和城郊地区报告的疟疾发病率较高。本研究对三个城市进行了城市景观分析，以确定可能导致城市环境中疟疾发病率上升的疟疾传播指标和人类行为。具体而言，评估了蚊虫媒介生物学特性和人类睡眠行为，包括户外睡眠习惯，以指导针对目标蚊虫控制干预措施的最佳部署。
2019 年 5 月至 12 月，在塞内加尔首都达喀尔之后人口最多的三个城市——迪尔布尔、考拉克和图巴，采用人诱停落法和拟除虫菊酯喷雾法进行了纵向昆虫学监测。此外，还在这些城市的随机选定房屋和宗教学校住宅中开展了家庭调查，以评估房屋结构、睡眠空间、睡眠行为以及居民对疟疾和病媒控制措施的了解情况。
在所有调查地点采集的 8240 只按蚊中，99.4%（8191 只）为冈比亚按蚊复合体，且主要为冈比亚按蚊（99%）。考拉克采集的冈比亚按蚊复合体数量高于迪尔布尔和图巴（77.7%，n=6496）。总的平均人诱停落率为每夜每人 14.2 次（b/p/n），户外诱停率（15.9 b/p/n）高于室内诱停率（12.5 b/p/n）。总的平均昆虫接种率范围为 3.7 感染性叮咬/人/年（ib/p/y），从迪尔布尔的 3.7 到考拉克的 40.2。所有地点记录的嗜人率均较低（平均 35.7%）。在接受调查的 1202 户家庭中，约 24.3%的家庭成员会在户外睡觉，除了在 7 月至 10 月的短雨季期间。尽管他们了解疟疾的传播方式以及用于预防疟疾的病媒控制措施，但仍会在户外睡觉。
在三个被调查城市中，冈比亚按蚊是主要的疟疾传播媒介。该物种有户外叮咬的倾向，这对很大一部分在户外睡觉的人群构成了风险。由于该国目前实施的所有病媒控制措施都针对内栖性病媒，这些数据突显了人群保护方面的潜在差距，并呼吁采用针对户外叮咬疟疾媒介的补充工具和方法。
