Van Tien My, Le Trung Quang, Tran Bich Ngoc
Faculty of Veterinary Medicine, College of Agriculture, Can Tho University, Can Tho 94000, Vietnam.
Vet World. 2023 May;16(5):1092-1097. doi: 10.14202/vetworld.2023.1092-1097. Epub 2023 May 24.
Canine distemper (CD) caused by the CD virus (CDV) has a high mortality rate that severely affects dog populations and other terrestrial carnivores worldwide. However, the genetics of CDV strains circulating in various regions in Vietnam, especially the Mekong Delta, remains unclear. This study aimed to characterize the molecular status of CDV strains circulating in the Mekong Delta, Vietnam.
Ocular/nasal swabs were collected from 550 dogs with clinically suspected CDV infection from veterinary clinics in three Vietnamese provinces. A reverse transcription-polymerase chain reaction on the part of the hemagglutinin gene was performed. A phylogenetic tree was constructed to analyze the relationship between the detected CDV and GenBank sequences.
The molecular study demonstrated that 4.18% (23/550) of the dogs were positive for CDV. The clinical findings revealed that the positive dogs exhibited clinical signs of distemper. The phylogenetic analysis indicated that the identified CDV sequences were clustered in the same branch with the genotype Asia-1 and distantly related to the vaccine strains. Notably, the CDV sequences detected in this study were grouped with the sequences previously found in southeast Vietnam; however, they were distant from those found in the north.
The present study confirmed the presence of CDV and to the best of our knowledge, highlighted for the first time that the CDV strains circulating in the Mekong Delta of Vietnam belong to the genotype Asia-1.
由犬瘟热病毒（CDV）引起的犬瘟热（CD）死亡率很高，严重影响全球犬类种群和其他陆生食肉动物。然而，越南各地区尤其是湄公河三角洲流行的CDV毒株的遗传学特征仍不清楚。本研究旨在描述越南湄公河三角洲流行的CDV毒株的分子特征。
从越南三个省份的兽医诊所收集了550只临床疑似感染CDV的犬的眼/鼻拭子。对血凝素基因部分进行逆转录-聚合酶链反应。构建系统发育树以分析检测到的CDV与GenBank序列之间的关系。
分子研究表明，4.18%（23/550）的犬CDV呈阳性。临床检查发现，阳性犬表现出犬瘟热的临床症状。系统发育分析表明，鉴定出的CDV序列与亚洲-1基因型聚集在同一分支，与疫苗株亲缘关系较远。值得注意的是，本研究中检测到的CDV序列与越南东南部先前发现的序列归为一组；然而，它们与北部发现的序列相距较远。
本研究证实了CDV的存在，据我们所知，首次强调了在越南湄公河三角洲流行的CDV毒株属于亚洲-1基因型。
