UF/IFAS Entomology and Nematology Department, University of Florida, 1881 Natural Area Dr, Gainesville, FL.
J Med Entomol. 2020 Jul 4;57(4):1314-1317. doi: 10.1093/jme/tjaa028.
The lone star tick, Amblyomma americanum Linnaeus, is ubiquitously present in the southeastern United States and will readily parasitize humans and companion animals. Fipronil is the active ingredient in several topically applied products used to manage ticks and fleas on companion animals. Reducing ectoparasite infestations on companion animals decreases the risk that pathogens vectored by these pests are transmitted to these animals and their owners. However, dependence on acaricides can promote the development of resistance. In this study, the Food and Agriculture Organization of the United Nations larval packet test was used to determine the lethal concentration (LC) values and discriminating concentration (DC) for fipronil in the lone star tick. The DC was calculated as 0.02080%. The low magnitude of the DC value suggests that fipronil is an effective active ingredient for A. americanum management. With the LC and DC values determined, emergent resistance can be monitored, potentially allowing for intervention should tolerance develop in A. americanum populations that are in frequent contact with humans and their companion animals.
孤星蜱，美洲钝眼蜱（Linnaeus），广泛存在于美国东南部，很容易寄生在人类和伴侣动物身上。氟虫腈是几种局部应用产品的有效成分，用于管理伴侣动物的蜱和跳蚤。减少伴侣动物的外寄生虫感染，降低了这些害虫传播的病原体传播给这些动物及其主人的风险。然而，对杀螨剂的依赖会促进抗性的发展。在这项研究中，联合国粮食及农业组织幼虫包被测试用于确定氟虫腈对孤星蜱的致死浓度（LC）值和区分浓度（DC）。DC 计算为 0.02080%。DC 值的低幅度表明氟虫腈是管理美洲钝眼蜱的有效活性成分。随着 LC 和 DC 值的确定，可以监测新出现的抗性，潜在地允许在经常与人类及其伴侣动物接触的美洲钝眼蜱种群中出现耐药性时进行干预。
