Shalaby Hatem A
Department of Parasitology and Animal Diseases, National Research Center, Giza, Egypt.
Iran J Parasitol. 2013 Jan;8(1):18-32.
Many parasitic helminthes of veterinary importance have genetic features that favor development of anthelmintic resistance, this becoming a major worldwide constrain in livestock production. The development of anthelmintic resistance poses a large threat to future production and welfare of grazing animals. Development of variable degrees of resistance among different species of gastrointestinal nematodes has been reported for all the major groups of anthelmintic drugs. It has been observed that frequent usage of the same group of anthelmintic; use of anthelmintics in sub-optimal doses, prophylactic mass treatment of domestic animals and frequent and continuous use of a single drug have contributed to the widespread development of anthelmintic resistance in helminthes. The degree and extent of this problem especially with respect to multidrug resistance in nematode populations is likely to increase. Maintaining parasites in refugia and not exposed to anthelmintics, seems to be a key point in controlling and delaying the development of resistance, because the susceptible genes are preserved. Targeted selective treatments attract the interest of scientists towards this direction. Additionally, adoption of strict quarantine measures and a combination drug strategy are two important methods of preventing of anthelmintic resistance. Experience from the development of anthelmintic resistance suggests that modern control schemes should not rely on sole use of anthelmintics, but employ other, more complex and sustainable recipes, including parasite resistant breeds, nutrition, pasture management, nematode-trapping fungi, antiparasitic vaccines and botanical dewormers. Most of them reduce reliance on the use of chemicals and are environmental friendly. Finally, if new anthelmintic products are released, an important question will be raised about how they should be used. It is suggested that slowing the development of resistance to a new class are likely to be gained by releasing it in combination with one or more of the older anthelmintic classes, especially where efficacy of the older active(s) remains high.
许多具有兽医重要性的寄生蠕虫具有有利于抗驱虫药耐药性发展的遗传特征，这已成为全球畜牧业生产的主要制约因素。抗驱虫药耐药性的发展对放牧动物未来的生产和健康构成了巨大威胁。对于所有主要类别的驱虫药，均已报道不同种类的胃肠线虫出现了不同程度的耐药性。据观察，同一类驱虫药的频繁使用；以次优剂量使用驱虫药、对家畜进行预防性群体治疗以及频繁且持续使用单一药物，都促成了蠕虫中抗驱虫药耐药性的广泛发展。这个问题的严重程度和范围，尤其是线虫群体中的多药耐药性，可能会增加。将寄生虫置于未接触驱虫药的避难所中，似乎是控制和延缓耐药性发展的关键，因为易感基因得以保留。有针对性的选择性治疗引起了科学家们在这个方向上的兴趣。此外，采取严格的检疫措施和联合用药策略是预防抗驱虫药耐药性的两种重要方法。抗驱虫药耐药性发展的经验表明，现代控制方案不应仅依赖于驱虫药的单独使用，而应采用其他更复杂且可持续的方法，包括抗寄生虫品种、营养、牧场管理、捕食线虫真菌、抗寄生虫疫苗和植物驱虫剂。它们中的大多数减少了对化学药品的依赖，并且对环境友好。最后，如果推出新的驱虫药产品，将引发一个重要问题，即应如何使用它们。建议将其与一种或多种较老的驱虫药类别联合使用，可能会减缓对新类别耐药性的发展，特别是在较老活性成分的疗效仍然很高的情况下。
