Malaria was eliminated from Sri Lanka in 2013. However, the influx of infected travelers and the presence of potent anopheline vectors can re-initiate transmission in Jaffna city, which is separated by a narrow strait from the malaria-endemic Indian state of Tamil Nadu. Anopheline larvae were collected from different habitats in Jaffna city and the susceptibility of emergent adults to DDT, malathion and deltamethrin investigated. Anopheline larvae were found in wells, surface-exposed drains, ponds, water puddles and water storage tanks, with many containing polluted, alkaline and brackish water. Anopheles culicifacies, An. subpictus, An. stephensi and An. varuna were identified in the collections. Adults of the four anopheline species were resistant to DDT. Anopheles subpictus and An. stephensi were resistant while An. culicifacies and An. varuna were possibly resistant to deltamethrin. Anopheles stephensi was resistant, An. subpictus possibly resistant while An. varuna and An. culicifacies were susceptible to malathion. DNA sequencing showed a L1014F (TTA to TTC) mutation in the IIS6 transmembrane segment of the voltage-gated sodium channel protein in deltamethrin-resistant An. subpictus—a mutation previously observed in India but not Sri Lanka. Anopheles subpictus in Jaffna, like An. stephensi, may have recently originated in coastal Tamil Nadu. Besides infected overseas travelers, wind- and boat-borne carriage of Plasmodium-infected anophelines across the Palk Strait can potentially reintroduce malaria transmission to Jaffna city. Adaptation to diverse larval habitats and resistance to common insecticides in anophelines are identified as potential problems for vector control should this happen.

中文翻译：

---

控制斯里兰卡北部贾夫纳市疟疾传播可能再次发生的背景下的按蚊生物经济学，抗药性和跨国扩散

2013年，斯里兰卡从疟疾中消除了疟疾。但是，受感染旅行者的涌入和强效按蚊载体的存在可以重新启动贾夫纳市的传播，该市与疟疾流行的印度泰米尔纳德邦相距甚远。从贾夫纳市不同的栖息地收集了按蚊幼虫，调查了成年成年人对滴滴涕，马拉硫磷和溴氰菊酯的敏感性。在井，暴露于地面的排水沟，池塘，水坑和储水罐中发现了按蚊幼虫，其中许多含有受污染的，碱性和微咸水。古按蚊，An。亚种，安。斯蒂芬斯和安。varuna在集合中被识别。四种按蚊种的成虫均对滴滴涕有抗药性。Subpictus和An。斯蒂芬斯抵抗而安。古迹和安。瓦鲁纳可能对溴氰菊酯有抗性。斯蒂芬按蚊是抗药性的。亚种可能抵抗而安。瓦鲁纳和安。古迹容易发生马拉硫磷。DNA测序显示耐溴氰菊酯的An。中电压门控钠通道蛋白的IIS6跨膜区段中存在L1014F（从TTA到TTC）突变。亚picpictus-以前在印度但未在斯里兰卡观察到的突变。贾夫纳的按蚊亚种，就像An。斯蒂芬斯，可能最近起源于泰米尔纳德邦沿海地区。除了受感染的海外旅行者以外，风和船载疟原虫感染的按蚊的风行都可以穿越帕克海峡，从而有可能再次将疟疾传播到贾夫纳市。