Table_1_Mini Review: Antimicrobial Control of Chlamydial Infections in Animals: Current Practices and Issues.DOCX

Chlamydia are a genus of successful obligate intracellular pathogens spread across humans, wildlife, and domesticated animals. The most common species reported in livestock in this genus are Chlamydia abortus, Chlamydia psittaci, Chlamydia suis, and Chlamydia pecorum. Chlamydial infections trigger a series of inflammatory disease-related sequelae including arthritis, conjunctivitis, pneumonia, and abortion. Other bacteria in the phylum Chlamydiae have also been reported in livestock and wildlife but their impact on animal health is less clear. Control of chlamydial infections relies on the use of macrolides, fluoroquinolones, and tetracyclines. Tetracycline resistance (TETR) reported for porcine C. suis strains in association with the use of tetracycline feed is a potentially significant concern given experimental evidence highlighting that the genetic elements inferring TETR may be horizontally transferred to other chlamydial species. As documented in human Chlamydia trachomatis infections, relapse of infections, bacterial shedding post-antibiotic treatment, and disease progression despite chlamydial clearance in animals have also been reported. The identification of novel chlamydiae as well as new animal hosts for previously described chlamydial pathogens should place a renewed emphasis on basic in vivo studies to demonstrate the efficacy of existing and new antimicrobial treatment regimes. Building on recent reviews of antimicrobials limited to C. trachomatis and C. suis, this review will explore the use of antimicrobials, the evidence and factors that influence the treatment failure of chlamydial infections in animals and the future directions in the control of these important veterinary pathogens.

沙眼衣原体属是一类在人类、野生动物及家畜中广泛传播的成功的专性细胞内病原体。在本属中，报告于家畜中最常见的物种包括流产衣原体、鹦鹉衣原体、猪衣原体和猪肺炎衣原体。衣原体感染可引发一系列与炎症性疾病相关的并发症，如关节炎、结膜炎、肺炎和流产。此外，据报道，属于衣原体门的其他细菌也存在于家畜和野生动物中，但它们对动物健康的影响尚不明确。衣原体感染的防控依赖于大环内酯类、氟喹诺酮类和四环素类药物的使用。由于实验证据表明，引起四环素抗性（TETR）的遗传元素可能水平转移至其他衣原体物种，因此，与四环素饲料使用相关的猪C. suis菌株的四环素抗性报告可能构成一个潜在的严重关切。正如人类沙眼衣原体感染所记录的，感染复发、抗生素治疗后细菌排出以及动物体内衣原体清除后的疾病进展等问题也已被报道。新发现的衣原体以及先前描述的衣原体病原体的新宿主应促使我们对基本体内研究给予新的重视，以证明现有和新抗菌治疗方案的有效性。基于近期对仅限于C. trachomatis和C. suis的抗菌药物的综述，本综述将探讨抗菌药物的使用、影响衣原体感染治疗失败的证据和因素，以及控制这些重要兽医病原体的未来方向。