| A virus strain was isolated from the lung of a dog suspected as canine distemper in Jilin. It was demonstrated to be canine distemper virus by a series of laboratory systemic identification and animal experiments, and was named CDV-JT1, then the H gene of the virus was sequenced .In 2009, a dog suspected as canine distemper was going to die in Jilin Province. The observed clinical symptoms of the dog included dry muzzle, mucopurulent ocular discharges and depression. Autopsy of the dog after euthanasia showed hemorrhagic pneumonia. Samples of lung was collected and inoculated in MDCK cell cultures after grinding. With continuous passages in cell culture, a typical cytopathic effect (CPE) of syncytia appeared in the cells. Under electron microscopy, the virus particle had the typical morphologic characteristics of paramyxoviruses. The test of physical and chemical properties indicating that CDV-JT1 strain contained peplos, it was sensitive to ethylether and lack of resistance to acid and high temperature and its nucleic acid type is RNA. CDV-JT1 strain was CDV-positive in the test of RT-PCR and direct mmunofluorescence assay. Dogs artificially infected by CDV-JT1 strain developed typical symptom of CD including fervescence, poor appetite , diarrhea , bloody diarrhea , rashes, ocular discharge and hardened footpads,and died during the 16～18d after challenged. Autopsy showed hemorrhagic pneumonia, emphysema, bladder petechial hemorrhage, intestinal wall petechial hemorrhage, tracheorrhagia, meningorrhagia. Pathological section observation revealed that the pulmonary alveoli was full of a large number of neutrophilic granulocyte, bladder telangiectasia and congestion and mucous edema. Sequencing analyses showed that CDV-JT1 strain belonged to the Asia-1 type CDV and was the prevalent virulent strain in China.The successful isolation of CDV-JT1 strain provided a basis for futher search on vaccination, epidemiology and pathogenicity.
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