A plate of viruses: Viral metagenomics of supermarket chicken, pork and beef from Brazil.

A viral metagenomics study was conducted in beef, pork, and chicken sold in supermarkets from Southern Brazil. From chicken, six distinct gyroviruses (GyV) were detected, including GyV3 and GyV6, which for the first time were detected in samples from avian species, plus a novel smacovirus species and two highly divergent circular Rep-encoding ssDNA (CRESS-DNA) viruses. From pork, genomes of numerous anelloviruses, porcine parvovirus 5 (PPV5) and 6 (PPV6), two new genomoviruses and two new CRESS-DNA viruses were found. Finally, two new CRESS-DNA genomes were recovered from beef. Although none of these viruses have history of transmission to humans, the findings reported here reveal that such agents are inevitably consumed in diets that include these types of meat.

Viral metagenomics in Brazilian Pekin ducks identifies two gyrovirus, including a new species, and the potentially pathogenic duck circovirus.

Viral metagenomics coupled to high-throughput sequencing has provided a powerful tool for large-scale detection of known and unknown viruses associated to distinct hosts and environments. Using this approach, known and novel viruses have been characterized from sylvatic and commercial avian hosts, increasing our understanding of the viral diversity in these species. In the present work we applied an exploratory viral metagenomics on organs (spleen, liver and bursa of Fabricious) of Pekin ducks from Southern Brazil. The virome contained sequences related to a known duck pathogen (duck circovirus) and a number of other circular ssDNA viruses. Additionally, we detected avian gyrovirus 9 (to date detected only in human feces) and one new avian gyrovirus species, to which is proposed the name avian gyrovirus 13 (GyV13). This study is expected to contribute to the knowledge of the viral diversity in Pekin ducks.

Novel Gyrovirus genomes recovered from free-living pigeons in Southern Brazil.

Wild birds carry a number of infectious agents, some of which may have pathogenic potential for the host and others species, including humans. Domestic pigeons (Columba livia) are important targets of study since these increasingly cohabit urban spaces, being possible spillover sources of pathogens to humans. In the present study, two genomes (PiGyV_Tq/RS/Br and PiGyV_RG/RS/Br), representative of Gyrovirus genus, family Anelloviridae, were detected in sera of free-living pigeons collected in Southern Brazil. The genomes exhibit less than 50% identity to previously described members of Gyrovirus genus, suggesting that they constitute a new viral species circulating in pigeons, to which the name "pigeon gyrovirus (PiGyV)" is proposed. The current study characterizes these two PiGyV genomes which, to date, are the first gyrovirus species identified in domestic pigeons.

A Novel and Divergent Gyrovirus with Unusual Genomic Features Detected in Wild Passerine Birds from a Remote Rainforest in French Guiana.

Sequence-independent amplification techniques have become important tools for virus discovery, metagenomics, and exploration of viral diversity at the global scale, especially in remote areas. Here, we describe the detection and genetic characterization of a novel gyrovirus, named GyV11, present in cloacal, oral, and blood samples from neotropical wild birds in French Guiana. The molecular epidemiology revealed the presence of GyV11 only in passerine birds from three different species at a low prevalence (0.73%). This is the first characterization and prevalence study of a gyrovirus carried out in resident wild bird populations in a remote region, and provides evidence of the fecal-oral route transmission and local circulation of the virus. The molecular phylogeny of gyroviruses reveals the existence of two distinct gyrovirus lineages in which GyV11 is phylogenetically distinct from previously reported gyroviruses. Furthermore, GyV11 is placed basal in the gyrovirus phylogeny, likely owing to its ancestral origin and marked divergence. This study also provides important insights into the ecology, epidemiology, and genomic features of gyroviruses in a remote neotropical rainforest. The pathogenesis of this virus in avian species or whether GyV11 can infect humans and/or chickens needs to be further investigated.

A third gyrovirus species in human faeces.

Until 2011 the genus Gyrovirus in the family Circoviridae consisted of a single virus (Chicken anemia virus or CAV) causing a common immunosuppressive disease in chickens when a second gyrovirus (HGyV) was reported on the skin of 4 % of healthy humans. HGyV is very closely related to a recently described chicken gyrovirus, AGV2, suggesting that they belong to the same viral species. During a viral metagenomic analysis of 100 human faeces from children with diarrhoea in Chile we identified multiple known human pathogens (adenoviruses, enteroviruses, astroviruses, sapoviruses, noroviruses, parechoviruses and rotaviruses) and a novel gyrovirus species we named GyV3 sharing <63 % similarity with other gyrovirus proteins with evidence of recombination with CAV in its UTR. Gyroviridae consensus PCR revealed a high prevalence of CAV DNA in diarrhoea and normal faeces from Chilean children and faeces of USA cats and dogs, which may reflect consumption of CAV-infected/vaccinated chickens. Whether GyV3 can infect humans and/or chickens requires further studies.

Variants of the recently discovered avian gyrovirus 2 are detected in Southern Brazil and The Netherlands.

A genome of a virus preliminarily named avian gyrovirus 2 (AGV2), a close relative to chicken anemia virus, was recently discovered in a chicken in the state of Rio Grande do Sul, Southern Brazil. To study the occurrence of AGV2 in Rio Grande do Sul and the neighboring state Santa Catarina, a number of adult chickens (n=108 and n=48, respectively) were tested for the presence of AGV2 DNA. An AGV2-specific PCR was developed, optimized and used to analyze DNA extracted from clinical samples. AGV2 DNA was detected in 98/108 (90.7%) of samples collected in the state of Rio Grande do Sul and 29/48 (60.4%) of the samples collected in the state of Santa Catarina. In order to check whether AGV2 DNA would be detected in samples from a geographically distant region, DNA from brain samples of 21 diseased chickens from the Netherlands were tested independently, by the same method. In such specimens, 9/21 (42.9%) brain tissue samples were found to contain AVG2 DNA. Sequence analysis of some of the PCR products demonstrated that the amplified AGV2 sequences could vary up to 15.8% and could preliminarily be divided in three groups. This indicated the occurrence of variants of AGV2, which may reflect differences in geographical origin and/or in biological properties. The data presented here provides evidence that AGV2 seems fairly distributed in chickens in Southern Brazil and that AGV2 also circulates in the Netherlands. Besides, circulating viruses display genetic variants whose significance should be further examined, particularly to determine whether AGV2 would play any role in chicken diseases.

Discovery of a genome of a distant relative of chicken anemia virus reveals a new member of the genus Gyrovirus.

A 2.4-kb phi29 polymerase amplification product from serum of a diseased chicken was cloned and sequenced. The 2383-nucleotide sequence showed about 40% identity to a representative genome of chicken anemia virus (CAV), the only member of the genus Gyrovirus, family Circoviridae. The new genome had an organization similar to that of CAV: a putative 5' untranscribed region of about 400 nt followed by three partially overlapping open reading frames encoding VP1, VP2 and VP3 homologs. The amino acid identities between these homologs and those of CAV were 38.8%, 40.3%, and 32.2%, respectively. Based on these limited similarities, it is proposed that the newly identified virus is a member of a new species in the genus Gyrovirus. For this new species, the name Avian gyrovirus 2 (AGV2) is proposed.