Molecular surveillance of canine distemper virus in diarrhoetic puppies in northeast China from May 2014 to April 2015

LI, Chunqiu; GUO, Donghua; WU, Rui; KONG, Fanzhi; ZHAI, Junjun; YUAN, Dongwei; SUN, Dongbo

The CDV-positive rate in feces of diarrhoetic dogs has been reported to be 8.7% (9/104), 1.4% (110/7,829), 2.3% (12/526), 1.6% (46/2,855), 2.5% (7/674), 1.0% (5/486) in Brazil, the U.S.A., Australia, Canada, the U.K. and Japan by using real-time PCR [9] . The CDV-positive rate identified in our study was significantly higher than that of other countries. CPV-2, CCoV, CaKV and CBoV had been reported to be associated with severe enteritis in puppies [4, 5] . In our previous studies, the positivity rates of CPV-2, CCoV, CaKV and CBoV had been revealed to be 47.26% (95/201), 28.36% (57/201), 17.91% (36/201) and 7.46% (15/201), respectively, within the same 201 samples investigated in the current study [7, 11, 13, 16] . The CDV-positive rate (24.88%) within these samples is nearly equal to CCoV's positivity rate. These data demonstrate that there is a very high prevalence of CDV in diarrhoetic dogs in northeastern China, making it one of main enteric pathogens in this region. The detailed information of the reference strains as follows: To investigate the co-infection of CDV with other pathogens, the 50 CDV-positive samples were subjected to detection of canine enteric viruses and bacteria. For viruses, canine parvovirus-2 (CPV-2), canine kobuvirus (CaKV), canine coronavirus (CCoV), and canine bocavirus (CBoV) were detected by either PCR or RT-PCR according to previously described protocols or reports [7, 10, 11, 16] . For bacteria, the main bacterial pathogens were detected by using the multiplex PCR panels described by [14] . The detailed information about co-infections of the CDV-positive dogs in northeast China was shown in Supplemental Table 1 .