Serological Evidence for Multiple Strains of Canine Norovirus in the UK Dog Population

Abstract

Noroviruses are associated with intestinal disease in humans, cows, pigs, mice, and, more recently, dogs. In 2007, the first canine norovirus (CNV) was identified and characterized in Italy. Subsequent studies have identified CNV in stools of dogs from Portugal, Greece, and the United States. To investigate the prevalence of CNV in the UK dog population, 228 canine stool samples were screened for CNV by qPCR, and 396 serum samples were screened for anti-CNV antibodies. qPCR of RNA extracted from canine stool samples did not reveal any CNV-positive samples, based on samples collected from diarrhoeic and control dogs in 2012–2013. CNV virus-like particles to three different CNV strains were produced using recombinant baculoviruses and a seroprevalence screen undertaken. Anti-CNV antibodies were identified at significant levels in canine serum; 38.1% of samples collected between 1999–2001 and 60.1% of samples collected in 2012–2013 were seropositive. The increase in seroprevalence over time (p<0.001) suggests that the CNV strains screened for are becoming more widespread. Variation in seroprevalence to different CNV strains was also identified. Two-thirds of the dogs were seropositive to a single strain, whereas the remaining third were seropositive to two or three of the strains analysed. This study has provided the first evidence that CNV is present in the UK, with seroprevalence identified to multiple circulating strains. This warrants further study and increased awareness of this recently discovered canine virus.

Seroprevalence of Canine Norovirus in 14 European Countries

“…Although a comparison of the seroprevalences between countries was not possible because the number of samples tested from several of the countries was limited, the detection of IgG antibodies in dogs from 12 of the 14 countries demonstrates that GVI.2 CNVs are widespread in dogs throughout Europe. The percentage of samples positive for GVI CNV antibodies in our study (36%) was higher than the 4.8% reported for GIV CNV antibodies in dogs from Italy (11) and fell within the range (38.1% to 60.1%) reported for the dog population of the United Kingdom (10). However, the 36% seropositivity found in this study must be interpreted with caution, since it may be an overestimate due to antibody cross-reactivity.…”

“…These data might indicate either a certain level of antibody cross-reactivity with GII.4 VLPs or multiple reactivities to canine GVI.2 and human norovirus in the same dog sera. Cross-reactivity to human norovirus and other canine norovirus strains is not expected to be present, as was demonstrated in recent studies (10,12). Conversely, the presence of antibodies to human GII.4 norovirus in dogs is plausible, since human GII.4 norovirus was recently detected in fecal samples from pet dogs that had been in direct contact with symptomatic persons who were confirmed to be infected with GII.4 norovirus (13).…”

“…Canine noroviruses (CNVs) are classified into GIV and GVI and have been detected in stool samples from dogs in Portugal, Italy, Greece, and Hong Kong (2,4,5,9). A recent seroepidemiological study in the United Kingdom found up to 60% of the dogs studied to be seropositive for CNV (10). To evaluate the prevalence of the recently described GVI CNV, we tested serum samples from dogs in 14 European countries for the presence of anti-GVI CNV IgG antibodies.…”

Genogroup IV and VI Canine Noroviruses Interact with Histo-Blood Group Antigens

“…Evidence for CNV infection has since been identified in Europe (18–20) and the Far East (21). CNV is believed to cause gastroenteritis in the canine host, though the virus has also been isolated from healthy dogs (19, 22).…”

Sewage surveillance reveals the presence of canine GVII norovirus and canine astrovirus in Uruguay

“…Phylogenetic analysis of the complete amino acid sequence of VP1 showed that these strains are distantly related to other NoV genogroups and were proposed as the seventh NoV genogroup (GVII) [5]. Furthermore, it was reported that there was a marked rise in seroprevalence of the novel GVII NoV over the last decade in dogs in the United Kingdom, suggesting that this genogroup is becoming increasingly common, at least in the UK [31]. However, there are no additional studies reporting GVII NoV strains in other countries.…”