Novel avian metaavulavirus isolated from birds of the family Columbidae in Taiwan

RNA sequencing of avian paramyxovirus (Paramyxoviridae, Avulavirinae) isolates from wild mallards in Belgium, 2021: complete genomes and coinfections

We used untargeted RNA sequencing to characterize three Avulavirinae isolates from pooled samples obtained from wild mallards in Belgium in 2021. The complete genome sequences of two avian Orthoavulavirus-1 (AOAV-1) strains and one avian Paraavulavirus-4 (APMV-4) strain were determined confirming hemagglutination inhibition testing of the virus isolates. In addition, the applied sequencing strategy identified an avian influenza virus (AIV) coinfection in all three virus isolates, confirming weak-positive AIV realtime RT-PCR results from the original sample material. In one AOAV-1 isolate, partial sequences covering all genome segments of an AIV of subtype H11N9 could be de novo assembled from the sequencing data. Besides an AIV coinfection, RNA metagenomic data from the APMV-4 isolate also showed evidence of Alpharetrovirus and Megrivirus coinfection. In total, two AOAV-1 of Class II, genotype I.2 and one APMV-4 complete genome sequences were assembled and compared to publicly available sequences, highlighting the importance of surveillance for poultry pathogens in wild birds. Beyond the insights from full genome characterization of virus isolates, untargeted RNA sequencing strategies provide additional insights in the RNA virome of clinical samples as well as their derived virus isolates that are particularly useful when targeting wild avifauna reservoirs of poultry pathogens.

An Outbreak of Newcastle Disease Virus in the Moscow Region in the Summer of 2022

In August 2022 on a backyard farm in the Moscow region of Russia, mortality was observed among chickens, and all 45 birds of a particular farm died or were slaughtered after the onset of symptoms within a few days. Paramyxovirus was isolated from the diseased birds. Based on the nucleotide sequences of the F and NP gene fragments, it was determined that the virus belonged to subgenotype VII.1 AAvV-1 class II. The cleavage site of the F gene ₁₀₉SGGRRQKRFIG₁₁₉ and T in 546 and 555 position of the NP gene were typical for the velogenic type. The genetically closest NDV isolates were found in Iran. The mean time of death of 10-day-old chicken embryos upon infection with the minimal infectious dose was 52 h, which is typical for the velogenic pathotype. The virus caused 100% death of six-week-old chickens during oral infection as well as 100% mortality of all contact chickens, including those located in remote cages, which proves the ability of the virus to spread not only by the fecal-oral route but also by the aerosol route. That demonstrates a high level of pathogenicity and contagiousness of the isolated strain for chicken. However, mice intranasally infected with high doses of the virus did not die.

Prevalence and genetic diversity of coronaviruses, astroviruses and paramyxoviruses in wild birds in southeastern Kazakhstan

Wild birds are natural reservoirs of many emerging viruses, including some zoonoses. Considering that the territory of Kazakhstan is crossed by several bird migration routes, it is important to know pathogenic viruses circulating in migratory birds in this region. Therefore, the aim of this study was to identify the host range, diversity and spatial distribution of avian paramyxoviruses, coronaviruses, and astroviruses in free-ranging wild birds in the southeastern region of Kazakhstan. For this purpose, we collected tracheal and cloacal swabs from 242 wild birds belonging to 51 species and screened them using conventional PCR assays. Overall, 4.1% (10/242) and 2.9% (7/242) of all examined birds tested positive for coronaviruses and astroviruses, respectively. Coronaviruses were found in the orders Pelecaniformes (30%; 3/10), Charadriiformes (30%; 3/10), Columbiformes (20%; 2/10), Anseriformes (10%; 1/10), and Passeriformes (10%; 1/10). All detected strains belonged to the genus Gammacoronavirus. Astroviruses were detected in birds representing the orders Passeriformes (57%; 4/7), Coraciiformes (14%; 1/7), Charadriiformes (14%; 1/7), and Columbiformes (14%; 1/7). Paramyxoviruses were observed in only two birds (0.8%; 2/242). Both strains were closely related to the species APMV-22, which had not been previously detected in Kazakhstan. Phylogenetic analysis of the partial RdRp gene sequences of the virus strains revealed three different clades of astroviruses, two clades of coronaviruses, and one clade of paramyxoviruses. The results of this study provide valuable information on the diversity and spatial distribution of paramyxoviruses, coronaviruses, and astroviruses in wild birds in southeastern Kazakhstan and highlight the importance of further thorough monitoring of wild birds in this region.

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First study on CoVs and AstroVs in wild birds in Kazakhstan.

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APMVs, CoVs and AstroVs are confirmed by RT-PCR and partial RdRp gene sequencing.

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The CoVs prevalence is higher in aquatic birds as compared to terrestrial species.

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The obtained CoV strains belong to the genus Gammacoronavirus

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Strains closely related to APMV-22 not previously detected in Kazakhstan are shown.

Genetic diversity of avian paramyxoviruses isolated from wild birds and domestic poultry in Taiwan between 2009 and 2020

Avian paramyxoviruses (APMVs) belonging to the subfamily Avulavirinae within the family Paramyxoviridae. APMVs consist of twenty-two known species and are constantly isolated from a wide variety of avian species around the world. In this study, the APMV isolates obtained from wild birds and domestic poultry during 2009–2020 in Taiwan were genetically characterized by phylogenetic analysis of their complete fusion protein gene or full-length genome. As a result, 57 APMV isolates belonging to seven different species were obtained during this period and subsequently identified as APMV-1 (n=17), APMV-2 (n=1), APMV-4 (n=25), APMV-6 (n=8), APMV-12 (n=2), APMV-21 (n=2) and APMV-22 (n=2). Sanger sequencing was performed to provide 22 full-length genome sequences and 35 complete fusion protein gene sequences for the APMV isolates. Phylogenetic analysis showed that the recovered viruses were closely related to Eurasian strains, except five class I APMV-1 and four APMV-4 isolates were related to North America strains. Our findings provided more evidence for the intercontinental transmission of APMVs between Eurasia and North America by wild birds. In addition, according to the criteria of the classification system based on complete fusion protein gene sequences, three novel genotypes within APMV-2, APMV-12, and APMV-22 were identified. Together, this investigation provided a broader perspective on the genetic diversity, evolution, and distribution of APMVs in multiple avian host species sampled in Taiwan.

2021 Taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales

In March 2021, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by four families (Aliusviridae, Crepuscuviridae, Myriaviridae, and Natareviridae), three subfamilies (Alpharhabdovirinae, Betarhabdovirinae, and Gammarhabdovirinae), 42 genera, and 200 species. Thirty-nine species were renamed and/or moved and seven species were abolished. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.

Occurrence and Role of Selected RNA-Viruses as Potential Causative Agents of Watery Droppings in Pigeons

The diseases with watery droppings (diarrhea and/or polyuria) can be considered some of the most severe health problems in domestic pigeons of various ages. Although they do not always lead to bird death, they can contribute to poor weight gains and hindered development of young pigeons and, potentially, to poor racing results in sports birds. The gastrointestinal tract disorders of pigeons may be of various etiology, but some of the causative agents are viral infections. This review article provides information collected from scientific reports on RNA-viruses belonging to the Astroviridae, Picornaviridae, and Coronaviridae families; the Avulavirinae subfamily; and the Rotavirus genus that might be implicated in such health problems. It presents a brief characterization, and possible interspecies transmission of these viruses. We believe that this review article will help clinical signs of infection, isolation methods, occurrence in pigeons and poultry, systemize and summarize knowledge on pigeon enteropathogenic viruses and raise awareness of the importance of disease control in pigeons.