Detection Of Kobuvirus Research Articles

Molecular detection of kobuviruses in livestock in Northern Ireland and the Republic of Ireland.

Kobuviruses have been detected in a wide range of mammals including cats, dogs, pigs, cattle, goats, sheep and bats. Kobuviruses have been detected in symptomatic and asymptomatic animals; however, the clinical significance of infection in animals is still unclear. To date, there is no information regarding kobuvirus prevalence in livestock in Ireland. This study reports the first detection of kobuviruses in pigs, bovines and ovines using quantitative PCR. In this study, mesenteric lymph node was collected from cattle (n=57), pigs (n=53) and sheep (n=50) from farms in Northern Ireland and the Republic of Ireland, from animals which had been submitted by private veterinary practitioners from 2009 to 2011 for routine post mortem and clinico-pathological examination. Kobuviruses were detected in 14 cows (24.5%), 5 pigs (9.4%) and 1 sheep (2%). Phylogenetic analysis of Irish kobuviruses from cattle and pigs revealed that the isolates clustered according to their host species. Interestingly, the sheep kobuvirus clustered with bovine kobuviruses detected in this study and other published kobuvirus strains. The data presented in this study contributes to the understanding of the epidemiology of these viruses in animals and to the genetic diversity that these viruses possess.

Molecular detection of kobuviruses in European roe deer (Capreolus capreolus) in Italy.

Kobuvirus RNA was found in 6.6 % (13/198) of stool specimens from roe deer (Capreolus capreolus) captured during the regular hunting season. Upon sequence analysis of a fragment of the 3D gene, nine strains displayed the highest nucleotide sequence identity (91.2-97.4 %) to bovine kobuviruses previously detected in either diarrhoeic or asymptomatic calves. Interestingly, four strains were genetically related to the newly discovered caprine kobuviruses (84.2-87.6 % nucleotide identity) identified in black goats in Korea.

First detection of kobuvirus in farm animals in Brazil and the Netherlands

Animal kobuviruses have been described in pigs, cattle, sheep and bats in countries in Asia and Europe. The virus can be detected in fecal and serum samples of infected animals with or without diarrhea, but most of the clinical as well as epidemiological features of kobuvirus infection are still unknown. This study reports the first detection of kobuvirus in farm animals from Brazil and the Netherlands and the molecular analysis of the detected strains. In Brazil, 53% (61/115) of the pigs (suckling, weaned and sows) were shedding porcine kobuvirus in feces, while in the Netherlands 16.7% (3/18) of the tested weaned pigs were infected. Kobuviruses detected in fecal samples of pigs in Brazil showed association (p=0.0002) with diarrhea. In pig serum, kobuvirus was detected at different ages (3, 21, 36, 60, 75, and 180days), with an overall rate of 76.7% (23/30). The sequencing of amplicons detected in serum of pigs of different ages suggested reinfection and no persistent infection. Kobuvirus was also detected in sheep and cattle feces from Brazil and the Netherlands, respectively. Phylogenetic analyses of Brazilian and Dutch kobuviruses from pig, cattle and sheep revealed genetic variability, particularly in one strain detected in sheep feces, which was more closely related to human Aichi virus. The molecular and phylogenetic analyses performed with other published kobuvirus strains and the strains presented in this study, showed that, in most of the cases, kobuvirus seems to group according to host species, but not to geographical region of origin. The data presented in this study contribute to the comprehension of kobuvirus epidemiology and also to the molecular identification of kobuvirus strains circulating worldwide.

Molecular detection of kobuvirus sequences in stool samples collected from healthy pigs in Japan

This study reports the detection and genetic characterization of porcine kobuvirus, a new member of the genus Kobuvirus in the family Picornaviridae. Among 293 fecal specimens collected from healthy pigs in 2009, in Japan, 133 (45.4%) were positive for kobuvirus using RT-PCR screening method. Of the positive specimens, 124 were obtained from pigs ≤6 months old, while 9 samples were from pigs >6 months old. Fifty-two representative strains of kobuviruses detected in this study were randomly selected and analyzed for their phylogenetic relationships with those other kobuvirus reference strains. The phylogenetic tree confirmed that 51 strains belonged to porcine kobuvirus and formed the exclusive branch with other porcine kobuvirus reference strains. In addition, the nucleotide sequence of H023/2009/JP shared very low levels of sequence identity with those of other porcine kobuvirus strains, but showed the highest level of sequence identity with bovine kobuvirus U-1 prototype strain. Our study demonstrated clearly that, porcine kobuvirus infection was common in healthy pigs and high prevalence of this virus was found in younger age of <6 months old of porcine populations in Tokyo and Hokkaido, Japan.

Molecular detection of kobuviruses and recombinant noroviruses in cattle in continental Europe

Two genotypes (Jena and Newbury2) and two intergenotype recombinant strains have been recognized in bovine noroviruses. Several studies have shown an apparent predominance of bovine infection with Newbury2-related (genotype 2) strains. Bovine stool samples were screened with two primer pairs targeting both the polymerase and the capsid genes. Among the predominant genotype 2 sequences, two were genetically related to the recombinant strain Thirsk10. The detection of sequences genetically related to Thirsk10, together with the very low rate of detection of Jena-related sequences, characterized the bovine norovirus population in Belgium, a representative region of continental Europe. Unexpectedly, bovine kobuvirus-related sequences were also amplified, extending their distribution area in Europe.

Candidate New Species ofKobuvirusin Porcine Hosts

Candidate New Species of<i>Kobuvirus</i>in Porcine Hosts