Molecular characterization of canine coronavirus strains circulating in Brazil

Abstract

To characterize canine coronavirus (CCoV) circulating in diarrheic puppies in Brazil, 250 fecal samples collected between 2006 and 2012 were tested. By using RT-PCR to partially amplify the M gene, CCoV RNA was detected in 30 samples. Sequence analysis of the M protein grouped eight strains with CCoV-I and another 19 with CCoV-II prototypes. To genotype/subtype the CCoV strains and assess the occurrence of single or multiple CCoV infections, RT-PCR of the S gene was performed, and 25/30 CCoV-positive strains amplified with one or two primer pairs. For 17/25 samples, single infections were detected as follows: six CCoV-I, nine CCoV-IIa and two CCoV-IIb. Eight samples were positive for more than one genotype/subtype as follows: seven CCoV-I/IIa and one CCoV-I/IIb. Sequence analysis revealed that the CCoV-I and IIa strains shared high genetic similarity to each other and to the prototypes. The Brazilian strains of CCoV-IIb displayed an aminoacid insertion that was also described in CCoV-IIb-UCD-1 and TGEV strains. Among the 25 CCoV-positive puppies, five had a fatal outcome, all but one of which were cases of mixed infection. The current study is the first reported molecular characterization of CCoV-I, IIa and IIb strains in Brazil.

Co-Circulation of Canine Coronavirus I and IIa/b with High Prevalence and Genetic Diversity in Heilongjiang Province, Northeast China

“…The total CCoV-positive rate reported here was lower than that in a previous report in 2006 in China [17]. In our study, CCoV-II, accounting for 84.21% of the 57 CCoV strains, was the predominant CCoV type in northeast China, which is line with most reports [11,17,34].…”

“…In our study, CCoV-positive rate showed clear differences among seasons and ages. The high prevalence of CCoV in the feces of diarrheic dogs aged 2-4 months was partially validated in other studies [11,32,33]. The high positive rate (56.14%) of CCoV was found between October and December, which may be associated with seasonal variations in northeast China.…”

“…In our study, 57 of 201 samples (28.36%) were positive for CCoV, and the CCoV-positive rate differed among the three districts of Heilongjiang province (26.95% for Harbin, 50% for Daqing, and 22.5% for Mudanjiang). The CCoV-positive rate in feces has been reported to be 43.75% ( [17], the Republic of Korea [31], Japan [32], Albania [33], Brazil [11], Italy, Belgium, the Netherlands, Germany, the United Kingdom, Spain, and France, respectively [34]. These data demonstrated that CCoV infections showed clear differences among the geographical regions.…”

“…Accumulating reports attributed that the increase in the severity of CCoV infections in dogs and the emergence of CCoV variants to potential recombination events within the S gene, which occur when a host is co-infected with different CCoV types [8][9][10]. Therefore, CCoV has received much attention as an emerging cause of infectious disease in dogs [4,[11][12][13][14][15][16].…”

Molecular characterization of canine parvovirus and canine enteric coronavirus in diarrheic dogs on the island of St. Kitts: First report from the Caribbean region

“…Whilst the molecular epidemiology of CCoV has been studied in different Asian and European countries (Cavalli et al, 2014;Buonavoglia, 2008, 2011;Decaro et al, 2010Decaro et al, , 2013Erles and Brownlie, 2009;Jeoung et al, 2014;McElligott et al, 2011;Ntafis et al, 2013;Soma et al, 2011;Wang et al, 2016), there is a dearth of data on distribution of CCoV genotypes from the North and South Americas. In Brazil, CCoV-I and CCoV-II strains, including pantropic CCoV-IIa variants were found to be circulating in the domestic dog population (Costa et al, 2014;Pinto et al, 2014). CCoV-IIa and −IIb genotypes have been associated with fatal enteritis in puppies in USA (Licitra et al, 2014).…”