Ainanshe O A, Jennings F W, Holmes P H
N.T.T.C.P., Somalia.
Trop Anim Health Prod. 1992 May;24(2):65-73. doi: 10.1007/BF02356946.
Drug resistance by pathogenic trypanosomes in Somali livestock has been suspected for some time but there have been few attempts to examine this problem in detail. Field isolations from two areas in the Lower Shabelle Region were obtained by injecting blood from trypanosome infected cattle into a recipient calf. Once the calf became parasitaemic it was treated with a standard dose of isometamidium chloride (Samorin, RMB) at 0.5 mg/kg. When a subsequent relapse infection developed, indicative of drug resistance, blood was taken and injected into groups of cattle and mice and these were treated with a range of doses of isometamidium chloride and diminazene aceturate (Berenil, Hoechst AC) to determine the degree of drug resistance. Both isolates showed remarkably high levels of drug resistance to both isometamidium chloride and diminazene aceturate, with minimum curative doses in cattle of > 2.0 mg/kg and 7.5 mg/kg for the two drugs respectively. Minimum curative doses in mice were approximately ten-fold those in cattle. Fortunately there have been a very few reports from Africa of such high levels of resistance of Trypanosoma congolense to this normal "sanative pair" of drugs. The results indicate that drug resistance could be an important constraint on the use of trypanocidal drugs to control trypanosomosis in Somalia.
一段时间以来，人们一直怀疑索马里家畜体内的致病性锥虫存在耐药性，但很少有人尝试详细研究这个问题。通过将感染锥虫的牛的血液注射到受体小牛体内，从下谢贝利地区的两个区域获得了野外分离株。一旦小牛出现寄生虫血症，就用0.5毫克/千克的标准剂量的氯咪啶（Samorin，RMB）进行治疗。当随后出现复发性感染，表明存在耐药性时，采集血液并注射到牛群和小鼠群体中，然后用一系列剂量的氯咪啶和乙酰氨基苯脒（贝尼尔，赫斯特AC）进行治疗，以确定耐药程度。两种分离株对氯咪啶和乙酰氨基苯脒均表现出极高的耐药水平，两种药物在牛体内的最低治愈剂量分别>2.0毫克/千克和7.5毫克/千克。小鼠体内的最低治愈剂量约为牛的十倍。幸运的是，非洲很少有关于刚果锥虫对这种常用“治疗组合”药物具有如此高耐药水平的报道。结果表明，耐药性可能是限制在索马里使用杀锥虫药物控制锥虫病的一个重要因素。
