Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China.
Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China.
BMC Vet Res. 2022 May 23;18(1):195. doi: 10.1186/s12917-022-03281-w.
Feline parvovirus (FPV) is a member of the family Parvoviridae, which is a major enteric pathogen of cats worldwide. This study aimed to investigate the prevalence of feline parvovirus in Beijing of China and analyze the genetic features of detected viruses.
In this study, a total of 60 (8.5%) parvovirus-positive samples were detected from 702 cat fecal samples using parvovirus-specific PCR. The complete VP2 genes were amplified from all these samples. Among them, 55 (91.7%) sequences were characterized as FPV, and the other five (8.3%) were typed as canine parvovirus type 2 (CPV-2) variants, comprised of four CPV-2c and a new CPV-2b strain. In order to investigate the origin of CPV-2 variants in cats, we amplified full-length VP2 genes from seven fecal samples of dogs infected with CPV-2, which were further classified as CPV-2c. The sequences of new CPV-2b/MT270586 and CPV-2c/MT270587 detected from feline samples shared 100% identity with previous canine isolates KT156833 and MF467242 respectively, suggesting the CPV-2 variants circulating in cats might be derived from dogs. Sequence analysis indicated new mutations, Ala91Ser and Ser192Phe, in the FPV sequences, while obtained CPV-2c carried mutations reported in Asian CPV variants, showing they share a common evolutionary pattern with the Asian 2c strains. Interestingly, the FPV sequence (MT270571), displaying four CPV-specific residues, was found to be a putative recombinant sequence between CPV-2c and FPV. Phylogenetic analysis of the VP2 gene showed that amino acid and nucleotide mutations promoted the evolution of FPV and CPV lineages.
Our findings will be helpful to further understand the circulation and evolution of feline and canine parvovirus in Beijing.
猫细小病毒（FPV）是细小病毒科的一个成员，是世界范围内猫的主要肠道病原体。本研究旨在调查中国北京地区猫细小病毒的流行情况，并分析检测到的病毒的遗传特征。
本研究中，用细小病毒特异性 PCR 从 702 份猫粪便样本中检测到 60 份（8.5%）细小病毒阳性样本。从所有这些样本中扩增出完整的 VP2 基因。其中，55 个（91.7%）序列被鉴定为 FPV，另外 5 个（8.3%）被鉴定为犬细小病毒 2 型（CPV-2）变异株，包括 4 个 CPV-2c 和一个新的 CPV-2b 株。为了研究猫中 CPV-2 变异株的起源，我们从感染 CPV-2 的 7 份犬粪便样本中扩增了全长 VP2 基因，进一步分为 CPV-2c。从猫样本中检测到的新 CPV-2b/MT270586 和 CPV-2c/MT270587 序列与以前的犬分离株 KT156833 和 MF467242 分别完全相同，表明在猫中循环的 CPV-2 变异株可能来源于犬。序列分析表明，FPV 序列中存在新的突变，Ala91Ser 和 Ser192Phe，而获得的 CPV-2c 携带了亚洲 CPV 变异株中报道的突变，表明它们与亚洲 2c 株具有共同的进化模式。有趣的是，发现一个显示四个 CPV 特异性残基的 FPV 序列（MT270571）是 CPV-2c 和 FPV 之间的推定重组序列。VP2 基因的系统进化分析表明，氨基酸和核苷酸突变促进了 FPV 和 CPV 谱系的进化。
我们的研究结果将有助于进一步了解北京地区猫和犬细小病毒的流行和进化。
