ECOLOGY OF INFLUENZA VIRUS IN WILD BIRD POPULATIONS IN CENTRAL ASIA

The study provides the results of AIV surveillance in Central Asia region during 2003-2009. We have analyzed. 2604 samples from wild birds. These samples were collected in Kazakhstan. (279), Mongolia (650), and Russia (1675). Isolated viruses from samples collected in Mongolia (13 isolates) and. in Russia (4 isolates) were described. Virological analysis has shown that 6 isolates belong to H3N6 subtype and. 5 isolates belong to H4N6 subtype. Two H1N1 influenza viruses, one H10N7 virus, two H3N8 viruses, and. H13N8 virus, which is new for Central Asia, have been also isolated. Samples were taken from birds of 6 orders, including several species, preferring water and semi-aquatic biotopes, one species, preferring dry plain regions, and one more species which can inhabit both dry and. water biotopes

ECOLOGY AND EVOLUTION OF HIGHLY PATHOGENIC AVIAN INFLUENZA H5N1 IN RUSSIA (2005-2012)

Russia covering a large part of Eurasia is of special interest for influenza virus ecology and evolution. The importance of this region has been confirmed by the previous outbreaks of HPAI H5N1 among wild birds from 2005 to 2010. Avian influenza virus surveillance is an important task prior the fundamental study and introduction. these data in practice. The article contains detailed comparative virological, molecular, pathogenic characteristics of H5N1 viruses isolated in Russia. Some molecular-epidemiological aspects are discussed. This study demonstrates the need for ongoing surveillance to detect new variants of influenza viruses and. facilitate prevention of outbreaks

Experimental infection of H5N1 HPAI in BALB/c mice

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

ECOLOGY OF INFLUENZA A VIRUSES, ISOLATED FROM GULLS OF THE RUSSIAN FAR EAST

During this research huge surveillance study, the role of Gulls as the nature host of influenza A viruses was established. Oral and cloacal samples from Gulls were collected on the territory of the Russian Far East. Fourteen influenza A viruses were isolated

RARE INFLUENZA VIRUS SUBTYPES ISOLATED FROM BIRDS OF THE SOUTH OF WESTERN SIBERIA

During avian influenza virus (AIV) surveillance in Russia, 2008, H15N4 subtype of the virus was isolated. All the H15 viruses had been previously isolated in Australia in 1979 and 1983. This is the first report about isolation. of AIV H15 subtype elsewhere. Genetic and. antigenic analyses were made. The significant antigenic differences between A/teal/Chany/7119/2008 strain and. reference strain A/shearwater/ Australia/2376/1979 were revealed. The results of this study show the necessity of monitoring for avian influenza viruses, study of pathogen genetic variability, evolution and ecology

An avian influenza A(H11N1) virus from a wild aquatic bird revealing a unique Eurasian-American genetic reassortment

Influenza surveillance in different wild bird populations is critical for understanding the persistence, transmission and evolution of these viruses. Avian influenza (AI) surveillance was undertaken in wild migratory and resident birds during the period 2007–2008, in view of the outbreaks of highly pathogenic AI (HPAI) H5N1 in poultry in India since 2006. In this study, we present the whole genome sequence data along with the genetic and virological characterization of an Influenza A(H11N1) virus isolated from wild aquatic bird for the first time from India. The virus was low pathogenicity and phylogenetic analysis revealed that it was distinct from reported H11N1 viruses. The hemagglutinin (HA) gene showed maximum similarity with A/semipalmatedsandpiper/Delaware/2109/2000 (H11N6) and A/shorebird/Delaware/236/2003(H11N9) while the neuraminidase (NA) gene showed maximum similarity with A/duck/Mongolia/540/2001(H1N1). The virus thus possessed an HA gene of the American lineage. The NA and other six genes were of the Eurasian lineage and showed closer relatedness to non-H11 viruses. Such a genetic reassortment is unique and interesting, though the pathways leading to its emergence and its future persistence in the avian reservoir is yet to be fully established

Genesis and spread of multiple reassortants during the 2016/2017 H5 avian influenza epidemic in Eurasia

Highly pathogenic avian influenza (HPAI) viruses of the H5 A/goose/Guangdong/1/96 lineage can cause severe disease in poultry and wild birds, and occasionally in humans. In recent years, H5 HPAI viruses of this lineage infecting poultry in Asia have spilled over into wild birds and spread via bird migration to countries in Europe, Africa, and North America. In 2016/2017, this spillover resulted in the largest HPAI epidemic on record in Europe and was associated with an unusually high frequency of reassortments between H5 HPAI viruses and cocirculating low-pathogenic avian influenza viruses. Here, we show that the seven main H5 reassortant viruses had various combinations of gene segments 1, 2, 3, 5, and 6. Using detailed time-resolved phylogenetic analysis, most of these gene segments likely originated from wild birds and at dates and locations that corresponded to their hosts' migratory cycles. However, some gene segments in two reassortant viruses likely originated from domestic anseriforms, either in spring 2016 in east China or in autumn 2016 in central Europe. Our results demonstrate that, in addition to domestic anseriforms in Asia, both migratory wild birds and domestic anseriforms in Europe are relevant sources of gene segments for recent reassortant H5 HPAI viruses. The ease with which these H5 HPAI viruses reassort, in combination with repeated spillovers of H5 HPAI viruses into wild birds, increases the risk of emergence of a reassortant virus that persists in wild bird populations yet remains highly pathogenic for poultry

Etiology of influenza-like illnesses in the population of Novosibirsk city in the 2018–2019 epidemic season

Influenza and other acute respiratory viral infections lead to a substantial incidence of severe cases and hospitalizations and so remain a global health problem. Within the frame of the Global Influenza Hospital Surveillance Network (GIHSN), we assessed the contribution of influenza and other respiratory viruses to severe cases of influenzalike diseases in patients hospitalized to the Novosibirsk infectious hospitals in the years 2018–2019. We analyzed 484 nasopharyngeal swabs collected from patients admitted to the hospitals with acute respiratory infections (ARI) using real-time polymerase chain reaction commercial kits. We confirmed viral etiology of ARI in 69.8% cases. Influenza viruses were detected in 47.1% cases, wherein concomitant circulation of influenza A(H1N1)pdm09 and A(H3N2) viruses was observed in 20.7% and 26% of patients, respectively, whereas influenza B virus was detected only in one sample. All analyzed influenza A viruses were antigenically similar to vaccine strains. Genetically, the Novosibirsk strains were closely related to influenza A viruses distributed in Russia and worldwide. Influenza A(H1N1)pdm09 virus was detected in all patients aged 0 to 14 years and required intensive care. Other respiratory viruses were detected in 36.4% of children and 5.8% of adults, and 8.3% of children had viral coinfection, whereas no cases of coinfection were detected in adults. The most common viruses in children were metapneumovirus — 12.8%, rhinovirus — 9.3% and respiratory syncytial virus — 8.0%. In adults, metapneumovirus, adenovirus, parainfluenza virus and rhinovirus were detected with a detection rate no exceeding 2%. In this study, we found no differences in the detection rate of the influenza virus due to concomitant chronic diseases, pregnancy, or smoking habits. At the same time, the detection rate of other respiratory viruses in non-smokers vs. smokers was significantly lower than in smokers and former smokers (26.15%, 66.67% and 62.50%, respectively). In addition, the level of detection of respiratory viruses in children with vs. without chronic pathology was significantly higher (55.3% and 38.7%, respectively). Thus, our and similar studies are important for monitoring and control of the infection

Антигенные свойства изолята коронавируса SARS-CoV-2/human/RUS/Nsk-FRCFTM-1/202, выделенного от пациента в Новосибирске

Objective: isolation of coronavirus SARS-CoV-2 from clinical sample of patient with COVID-19 in Novosibirsk; obtaining a purified and inactivated viral antigen and study of its antigenic properties. Materials and methods: virus isolation was carried out in Vero cell culture from nasopharyngeal swab positive on SARS-CoV-2 RNA. The efficiency of SARSCoV-2 replication in cell culture was assessed on the appearance of cytopathic effect (CPE) and the presence of viral RNA in cultural medium with reverse transcription – polymerase chain reaction (RT-PCR). Purification, concentration and inactivation of the viral preparation were carried out according to standard methods. The purity of the purified preparation and the profile of viral proteins were determined by electrophoresis in 10% polyacrylamide gel (PAG) with the addition of sodium dodecyl sulfate (SDS). The presence and specificity of viral proteins were detected using COVID-19 convalescent’s sera with enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Results: SARS-CoV-2/human/ RUS/Nsk-FRCFTM-1/2020 isolate was obtained after passage on Vero cells from a virus-containing clinical sample. A purified, concentrated, inactivated, whole-virion antigen was obtained. It contains three structural proteins: glycoprotein S (approximately 200 kDa), nucleoprotein N (48 kDa), and matrix protein M (20-25 kDa). All viral proteins were detected with serum antibodies of COVID-19 convalescents. Conclusion: SARS-CoV-2 coronavirus can be isolated in Vero cell culture. The antigenic specificity of the three structural viral proteins (S, N, and M) is preserved in the purified inactivated viral preparation. The inactivated whole-virion antigen of SARS-CoV-2/human/RUS/Nsk-FRCFTM-1/2020 isolate can be used to study the antigenic immunomodulating properties of viral proteins, to obtain immune sera of laboratory animals, and also as a component of test systems for the detection of specific antibodies with ELISA and immunoblotting.Цель: изоляция коронавируса SARS-CoV-2 из образцов носоглоточных мазков, положительных на наличие РНК SARS-CoV-2, получение инактивированного цельновирионного антигена и изучение его антигенных свойств. Материалы и методы: изоляцию вируса проводили на культуре клеток Vero из вируссодержащего образца клинического материала (мазок из носоглотки). Эффективность репликации вируса SARS-CoV-2 на культуре клеток оценивали по динамике появления цитопатического действия и наличию вирусной РНК при анализе культуральной жидкости методом обратной транскрипции – полимеразной цепной реакции. Очистку, концентрацию и инактивацию вирусного препарата проводили по стандартной методике. Степень чистоты очищенного препарата и профиль вирусных белков определяли методом электрофореза в 10% полиакриламидном геле с добавлением додецилсульфата натрия. Наличие и специфичность вирусных белков выявляли с помощью сывороток крови реконвалесцентов с диагнозом «COVID-19» методами иммуноферментного анализа и иммуноблоттинга. Результаты: из вируссодержащего клинического образца был выделен изолят SARS-CoV-2/human/RUS/ Nsk-FRCFTM-1/2020 и получен очищенный, концентрированный, инактивированный цельновирионный антиген, содержащий три структурных белка – гликопротеин S (примерно 200 кДа), нуклеопротеин N (48 кДа) и матриксный М (20-25 кДа), выявляемые антителами сывороток крови реконвалесцентов с диагнозом COVID-19. Заключение: показана возможность изоляции коронавируса SARS-CoV-2 на культуре клеток Vero. В очищенном вирусном препарате, инактивированном в лизирующем растворе, сохраняется антигенная специфичность трех структурных вирусных белков (S, N, и М), выявляемых антителами сывороток крови реконвалесцентов с диагнозом COVID-19. Инактивированный цельновирионный антиген изолята SARS-CoV-2/human/ RUS/Nsk-FRCFTM-1/2020 может быть использован для изучения антигенных иммуномодулирующих свойств вирусных белков, получения иммунных сывороток лабораторных животных, а также в качестве компонента тест-систем для выявления специфичных антител методом ИФА и иммуноблоттинга

Вариант вируса гриппа в, адаптированный к мышам, для изучения лечебной и профилактической эффективности противовирусных препаратов in vitro и in vivo

Objective: to develop a new antigenic relevance influenza B virus suitable for modeling influenza infection in mice to assess of in vivo and in vitro therapeutic and preventive efficacy of antiviral drugs.Materials and methods: was carried out an adaptation of influenza B virus in BALB/c mice. Was performed, comparative assessment of in vivo and in vitro pathogenicity of the parenta! virus and. adapted, influenza B virus. Was assessed, inhibition of neuraminidase with antiviral drugs (oseltamivir ethoxyacrylate and. Tamiflu) in relation to the adapted, influenza B virus.Results: adapted  influenza B virus (B/Novosibirsk/40/2017-MA strain) models non-lethal influenza infection with pronounced, clinical signs of the disease in experimental animals. Were described the destructive changes in lungs and. brain that increases during infection. Analysis of internal organs (lungs, brain, liver, heart, kidneys, spleen) were revealed viral load only in the lungs. Were evaluated, in vivo and in vitro efficacy of antiviral drugs (oseltamivir ethoxysuccinate and Tamiflu®) on the model of influenza infection. Were proved, the high, efficiency of the innovative drug — oseltamivir ethoxysuccinate.Conclusion: the antigen-relevant adapted, influenza B virus (B/Novosibirsk/40/2017-MA strain) can be used, to assess the drug effectiveness against influenza, as well as an additional tool for predicting the effectiveness of the vaccine against drifting strains.Цель: разработка нового, обладающего антигенной актуальностью, штамма вируса гриппа типа В, пригодного для моделирования гриппозной инфекции у экспериментальных мышей для оценки лечебной и профилактической эффективности противовирусных препаратов in vivo и in vitro.Mатериалы и методы: была проведена адаптация вируса гриппа В на мышах линии BALB/c. Выполнена сравнительная оценка патогенности родительского и адаптированного вариантов вируса гриппа В в экспериментах in vivo и in vitro. Используя адаптированный вариант вируса гриппа В, проведена оценка ингибирования нейраминидазы с помощью противовирусных лекарственных средств (осельтамивира этоксисукцинат, и Тамифлю®).Результаты: полученный адаптированный вариант, вируса гриппа В штамм. В/Novosibirsk/40/2017-MA моделирует у экспериментальных животных нелетальную гриппозную инфекцию с выраженными клиническими признаками заболевания. Описаны, деструктивные изменения в лёгких и головном, мозге, нарастающие в ходе инфекции. Вирусологический анализ внутренних органов (лёгкие, головной мозг, печень, сердце, почки, селезёнка) выявил репликацию вируса гриппа только в лёгких. На данной модели гриппозной инфекции проведена оценка эффективности противовирусных лекарственных средств (осель-тамивира этоксисукцинат, и Тамифлю®) in vivo и in vitro. Доказана высокая эффективность инновационного лекарственного средства осельтамивира этоксисукцинат..Заключение: полученный антигенно актуальный вирус гриппа В штамм В/Novosibirsk/40/2017-MA может, быть использован, для оценки эффективности противогриппозных препаратов, а также в качестве дополнительного инструмента прогнозирования эффективности вакцины, против дрейфующих штаммов