Phylogenetic and pathogenicity analysis of a novel lineage of caprine
parainfluenza virus type 3
Abstract
Caprine parainfluenza virus type 3 (CPIV3) was first identified in goats
named JS2013 in China. In 2019, a sheep herd broke a disease with
respiratory disease in Hebei province, China. In order to confirm the
pathogen of the disease, the nasal swabs, stool swabs and blood samples
were collected from the sheep. Virus isolation was performed on MDBK
cells and identification was conducted by RT-PCR. The complete genome of
the isolate was sequenced and phylogenetic analyzed. In order to
evaluate the pathogenicity of the virus, five seronegative sheep were
experimental infected with the virus suspension. The phylogenetic
analyses based on the complete genome and the M gene indicated that the
isolate strain was distinguished distinct from previously reported CPIV3
lineage of JS2013. The virus-inoculated sheep displayed the syndrome
with depression, cough, and fever. Virus shedding were detected by
RT-PCR from nasal swabs. All infected showed virus shedding during 2 -
21dpi and viremia could be detected in serum samples. Gross pathological
assessment of sheep in infected group showed gross lesion in the lungs.
Histopathological observation results indicated that lungs had mild to
moderate interstitial pneumonia , with thickened alveolar walls,
decreased alveolar space, and increased amounts of inflammatory cells
infiltration. This is the first report of pathogenicity of the novel
lineage of sheep-derived CPIV3. The results would be helpful for further
studies on the prevention and control strategies for CPIV3 infections in
goat and sheep.