Diagnosis of an Outbreak of Canine Distemper in Cynomolgus Monkeys in an Experimental Monkey Farm in 2019
10.12300/j.issn.1674-5817.2024.160
- VernacularTitle:2019年某实验猴养殖场食蟹猴犬瘟热暴发的诊断
- Author:
Chenjuan WANG
1
;
Lingyan YANG
2
;
Lipeng WANG
1
;
Xueping SUN
1
;
Jingwen LI
1
;
Lianxiang GUO
1
;
Rong RONG
2
;
Changjun SHI
1
Author Information
1. Suzhou Xishan Biotechnology Inc., Suzhou 215123, China
2. Department of Biological Sciences, School of Science, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
- Publication Type:Journal Article
- Keywords:
Canine distemper virus;
Cynomolgus monkey;
Nonhuman primates;
Phylogenetic analysis
- From:
Laboratory Animal and Comparative Medicine
2025;45(3):360-367
- CountryChina
- Language:Chinese
-
Abstract:
Objective To report the diagnosis of a canine distemper virus outbreak among a colony of cynomolgus monkeys at an experimental monkey farm in 2019. MethodsA total of 46 samples were collected from 21 diseased cynomolgus monkeys (exhibiting symptoms such as facial rash, skin scurf, runny nose, and diarrhea) and from one deceased monkey at an experimental monkey breeding farm in South China in late 2019, including serum, skin rash swabs, and anticoagulated whole blood, liver, lung, and skin tissues were submitted for testing. All submitted samples were tested for canine distemper virus gene fragments using real-time quantitative PCR, while immunohistochemical staining was performed to detect canine distemper virus nucleoprotein in lung tissues. The skin tissue of the deceased monkey was ground and sieved. The filtrate was inoculated into a monolayer MDCK cell line for virus isolation. Then, whole-genome sequencing was performed to identify the isolated virus. The Clustal Omega tool was used to align and analyze the homology of different Asian canine distemper virus isolates. A phylogenetic tree was constructed, followed by genetic evolutionary analysis. ResultsClinical retrospective analysis revealed that the diseased cynomolgus monkeys exhibited symptoms similar to those observed in cynomolgus monkeys infected with measles virus. Necropsy findings showed red lesions in the lungs and significant hemorrhage in the colonic mucosa. Real-time quantitative PCR detected canine distemper virus nucleic acid in the serum, skin rash swabs of the infected monkeys, and various tissue samples of the deceased monkey, all of which tested positive. Calculation based on the standard curve formula indicated the viral load was highest in the skin tissue. Immunohistochemical staining of the deceased monkey's lung tissue demonstrated aggregation of CDV nucleoprotein in alveolar epithelial cells, bronchi, and bronchioles. A CDV strain was isolated from the skin tissue of the deceased monkey. Phylogenetic analysis indicated that this strain shares the closest relationship (98.86%) with the Asian-1 type canine distemper virus strain CDV/dog/HCM/33/140816, previously identified in dogs in Vietnam. ConclusionBased on comprehensive analysis of clinical symptoms, nucleic acid detection, viral protein immunohistochemistry, and whole-genome sequencing results, the diagnosis confirms that the cynomolgus monkeys in this facility are infected with canine distemper virus. It is recommended to include canine distemper virus as a routine surveillance target in captive monkey populations. Additionally, this study provides a foundation for further research on the molecular biological characteristics of canine distemper virus.
