RESUMO
This study presents the isolation of influenza A(H5N8) virus clade 2.3.4.4b from a poultry worker during an outbreak of highly pathogenic avian influenza A(H5N8) among chickens at a poultry farm in Astrakhan, Russia in December 2020. Nasopharyngeal swabs collected from seven poultry workers were positive for influenza A(H5N8), as confirmed by RT-PCR and sequencing. The influenza A(H5N8) virus was isolated from one of the human specimens and characterised. Sporadic human influenza A(H5)2.3.4.4. infections represent a possible concern for public health.
Assuntos
Vírus da Influenza A Subtipo H5N8 , Influenza Aviária , Doenças das Aves Domésticas , Animais , Galinhas , Surtos de Doenças , Fazendas , Humanos , Vírus da Influenza A Subtipo H5N8/genética , Influenza Aviária/epidemiologia , Filogenia , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , Federação Russa/epidemiologiaRESUMO
The Astrakhan region of Russia is endemic for the number of arboviruses. In this paper, we describe the results of the detection of the list of neglected arboviruses in the Astrakhan region for the 2018 season. For the purpose of the study in-house PCR assays for detection of 18 arboviruses have been developed and validated using arboviruses obtained from Russian State Collection of Viruses. Pools of ticks (n = 463) and mosquitoes (n = 312) as well as 420 samples of human patients sera have been collected and analyzed. Using developed multiplex real-time PCR assays we were able to detect RNA of eight arboviruses (Crimean-Congo hemorrhagic fever virus, Dhori (Batken strain) virus, Batai virus, Tahyna virus, Uukuniemi virus, Inkoo virus, Sindbis virus and West Nile fever virus). All discovered viruses are capable of infecting humans causing fever and in some cases severe forms with hemorrhagic or neurologic symptoms. From PCR-positive samples, we were able to recover one isolate each of Dhori (Batken strain) virus and Crimean-Congo hemorrhagic fever virus which were further characterized by next-generation sequencing. The genomic sequences of identified Dhori (Batken strain) virus strain represent the most complete genome of Batken virus strain among previously reported.
Assuntos
Infecções por Arbovirus/virologia , Arbovírus/classificação , Arbovírus/genética , Culicidae/virologia , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Thogotovirus/genética , Carrapatos/virologia , Animais , Arbovírus/isolamento & purificação , Vírus Bunyamwera/classificação , Vírus Bunyamwera/genética , Vírus da Encefalite da Califórnia/classificação , Vírus da Encefalite da Califórnia/genética , Genoma Viral , Vírus da Febre Hemorrágica da Crimeia-Congo/classificação , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Patologia Molecular/métodos , Filogenia , RNA Viral , Federação Russa/epidemiologia , Sindbis virus/classificação , Sindbis virus/genética , Thogotovirus/classificação , Thogotovirus/isolamento & purificação , Vírus Uukuniemi/classificação , Vírus Uukuniemi/genética , Vírus do Nilo Ocidental/classificação , Vírus do Nilo Ocidental/genéticaRESUMO
Phlebovirus is an abundant and rather heterogeneous genus within the Phenuiviridae family (order Bunyavirales). The genus Phlebovirus is divided into two antigenic complexes, which also correspond to the main vector: sandflies/mosquitoes and ticks. Previously, only sandfly/mosquito-borne phleboviruses were associated with human disease, such as Rift Valley fever virus, Toscana virus, Sicilian and Naples Sandfly fever viruses and others. Until recently, tick-borne phleboviruses were not considered as human pathogens. After the discovery of severe fever with thrombocytopenia syndrome, interest to tick-borne phleboviruses has increased dramatically. In the last decade, many novel phleboviruses have been reported in different regions. Despite this, the diversity, ecology and pathogenicity of these viruses still remain obscure. The aim of this work was to study the diversity of phleboviruses in ticks collected in several regions of Russia. We used pan-phlebovirus RT-PCR assays based on multiple degenerate primers targeting the polymerase gene fragment. Arthropod specimens were collected from 2005 to 2018. A total of 5901 Ixodidae ticks combined into 1116 pools were screened. A total of 160 specific amplicons were produced. In three cases RT-PCR assays amplified two distinct viruses from same tick pools. Direct sequencing of amplicons and subsequent phylogenetic analysis revealed twelve representatives of divergent phlebovirus groups. Based on the distribution of pairwise nucleotide sequence identity values, a cut-off (88%) was suggested to distinguish tick-borne phleboviruses. According to this provisional criterion, two viruses found here could be termed novel, while ten viruses have been described in previous studies. Detected phleboviruses demonstrated almost perfect specificity to a tick species or, at least, a genus. The same pattern was observed for tick-borne phleboviruses found in different studies around the world. Viruses that grouped together on a phylogenetic tree and differed less than this sequence identity threshold suggested above were hosted by ticks from the same genus.
