Congenital tremor (CT) is a neurological disease that affects new-born piglets. It was described in 1922 and six different forms, designated type AI-V and type B, are described based on the causative agents, as well as specific histological findings in the central nervous system (CNS). The various forms present with identical clinical signs consisting of mild to severe tremor of the head and body, sometimes complicated with ataxia. By definition, all A-forms have hypomyelination of the CNS, whereas there are no histopathological lesions with the B-form. The cause of the A-II form was long unknown, however, at present several different viruses have been proposed as the causative agent: porcine circovirus-II (PCV-II), astrovirus, PCV-like virus P1, and atypical porcine pestivirus (APPV). Currently, APPV is the only virus that has been proven to fulfill Mokili's Metagenomic Koch's Postulates. Following infection of the pregnant sow, the virus passes the placental barrier and infects the fetus. Interestingly, no clinical signs of disease have been associated with APPV in adult pigs. Furthermore, other viruses cannot be ruled out as additional potential causes of CT. Given the increased interest and research in CT type A-II, the aim of this review is to summarize current knowledge.

中文翻译：

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仔猪先天性震颤 A-II 型综述

先天性震颤 (CT) 是一种影响新生仔猪的神经系统疾病。它于 1922 年被描述，并根据病原体以及中枢神经系统 (CNS) 的特定组织学发现描述了六种不同的形式，称为 AI-V 型和 B 型。各种形式都具有相同的临床症状，包括头部和身体的轻度至重度震颤，有时还伴有共济失调。根据定义，所有 A 型都有 CNS 髓鞘化，而 B 型没有组织病理学病变。A-II 型的病因长期以来一直未知，但目前已提出几种不同的病毒作为病原体：猪圆环病毒-II (PCV-II)、星状病毒、PCV 样病毒 P1 和非典型猪瘟病毒。 APP）。现在，APPV 是唯一被证明符合 Mokili 的宏基因组 Koch 假设的病毒。感染怀孕母猪后，病毒会通过胎盘屏障并感染胎儿。有趣的是，在成年猪身上没有出现与 APPV 相关的临床疾病迹象。此外，不能排除其他病毒是 CT 的其他潜在原因。鉴于对 A-II 型 CT 的兴趣和研究的增加，本综述的目的是总结当前的知识。