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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="other" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Russian Journal of Infection and Immunity</journal-id><journal-title-group><journal-title xml:lang="en">Russian Journal of Infection and Immunity</journal-title><trans-title-group xml:lang="ru"><trans-title>Инфекция и иммунитет</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2220-7619</issn><issn publication-format="electronic">2313-7398</issn><publisher><publisher-name xml:lang="en">SPb RAACI</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">1456</article-id><article-id pub-id-type="doi">10.15789/2220-7619-HIT-1456</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="article-type"><subject></subject></subj-group></article-categories><title-group><article-title xml:lang="en">2019–2020 herd immunity to seasonal influenza viruses prior to epidemic season and rate of severe disease cases</article-title><trans-title-group xml:lang="ru"><trans-title>Популяционный иммунитет к сезонным вирусам гриппа накануне эпидемического сезона и тяжелые случаи заболевания в 2019–2020 гг.</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2354-7688</contrib-id><name-alternatives><name xml:lang="en"><surname>Ilyicheva</surname><given-names>T. N.</given-names></name><name xml:lang="ru"><surname>Ильичева</surname><given-names>Т. Н.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p><bold>Tatyana N. Ilyicheva, </bold> PhD, MD (Biology), Associate Professor, Leading Researcher, Department of Zoonotic Infections and Influenza </p><p>630559, Novosibirsk Region, Koltsovo</p><p>Phone: +7 383 363-47-00. Fax: +7 383 336-74-09 </p></bio><bio xml:lang="ru"><p><bold>Ильичева Татьяна Николаевна, </bold> д.б.н., доцент, ведущий научный сотрудник отдела зоонозных инфекций и гриппа </p><p>630559, Новосибирская область, р.п. Кольцово</p><p>Тел.: 8 383 363-47-00. Факс: 8 383 336-74-09</p></bio><email>ilicheva_tn@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Kolosova</surname><given-names>N. P.</given-names></name><name xml:lang="ru"><surname>Колосова</surname><given-names>Н. П.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Leading Researcher, Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>к.б.н., ведущий научный сотрудник отдела зоонозных инфекций и гриппа </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>kolosova_np@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Durymanov</surname><given-names>A. G.</given-names></name><name xml:lang="ru"><surname>Дурыманов</surname><given-names>А. Г.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Senior Researcher, Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>старший научный сотрудник отдела зоонозных инфекций и гриппа  </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>gavrilych51@mail.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Torzhkova</surname><given-names>P. Yu.</given-names></name><name xml:lang="ru"><surname>Торжкова</surname><given-names>П. Ю.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Senior Investigator (Biologist), Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>старший лаборант-исследователь отдела зоонозных инфекций и гриппа </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>torzhkova_pyu@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Svyatchenko</surname><given-names>S. V.</given-names></name><name xml:lang="ru"><surname>Святченко</surname><given-names>С. В.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Junior Researcher, Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>младший научный сотрудник отдела зоонозных инфекций и гриппа  </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>svyatchenko_sv@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Bulanovich</surname><given-names>Y. A.</given-names></name><name xml:lang="ru"><surname>Буланович</surname><given-names>Ю. А.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Senior Investigator (Biologist), Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>старший лаборант-исследователь отдела зоонозных инфекций и гриппа </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>bulanovich_yua@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Ivanova</surname><given-names>E. V.</given-names></name><name xml:lang="ru"><surname>Иванова</surname><given-names>Е. В.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Virologist </p><p>Novosibirsk</p></bio><bio xml:lang="ru"><p>врач-вирусолог  </p><p>г. Новосибирск</p></bio><email>cgnso@cn.ru</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Ivanova</surname><given-names>K. I.</given-names></name><name xml:lang="ru"><surname>Иванова</surname><given-names>К. И.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Senior Investigator (Biologist), Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>старший лаборант-исследователь отдела зоонозных инфекций и гриппа </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>ivanova_ki@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Ryzhikov</surname><given-names>A. B.</given-names></name><name xml:lang="ru"><surname>Рыжиков</surname><given-names>А. Б.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Head of the Department of Zoonotic Infections and Influenza </p><p>Koltsovo, Novosibirsk Region</p></bio><bio xml:lang="ru"><p>к.б.н., зав. отделом зоонозных инфекций и гриппа </p><p>р.п. Кольцово, Новосибирская область</p></bio><email>ryzhik@vector.nsc.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">State Scientific Center of Virology and Biotechnology “Vector” of Rospotrebnadzor</institution></aff><aff><institution xml:lang="ru">ФБУН ГНЦ ВБ «Вектор» Роспотребнадзора</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Center for Hygiene and Epidemiology in Novosibirsk Region of Rospotrebnadzor</institution></aff><aff><institution xml:lang="ru">ФБУЗ Центр гигиены и эпидемиологии в Новосибирской области Роспотребнадзора</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2021-11-21" publication-format="electronic"><day>21</day><month>11</month><year>2021</year></pub-date><volume>11</volume><issue>5</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>927</fpage><lpage>933</lpage><history><date date-type="received" iso-8601-date="2020-04-11"><day>11</day><month>04</month><year>2020</year></date><date date-type="accepted" iso-8601-date="2021-05-30"><day>30</day><month>05</month><year>2021</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2021, Ilyicheva T.N., Kolosova N.P., Durymanov A.G., Torzhkova P.Y., Svyatchenko S.V., Bulanovich Y.A., Ivanova E.V., Ivanova K.I., Ryzhikov A.B.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2021, Ильичева Т.Н., Колосова Н.П., Дурыманов А.Г., Торжкова П.Ю., Святченко С.В., Буланович Ю.А., Иванова Е.В., Иванова К.И., Рыжиков А.Б.</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="en">Ilyicheva T.N., Kolosova N.P., Durymanov A.G., Torzhkova P.Y., Svyatchenko S.V., Bulanovich Y.A., Ivanova E.V., Ivanova K.I., Ryzhikov A.B.</copyright-holder><copyright-holder xml:lang="ru">Ильичева Т.Н., Колосова Н.П., Дурыманов А.Г., Торжкова П.Ю., Святченко С.В., Буланович Ю.А., Иванова Е.В., Иванова К.И., Рыжиков А.Б.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://iimmun.ru/iimm/article/view/1456">https://iimmun.ru/iimm/article/view/1456</self-uri><abstract xml:lang="en"><p>The aim was to analyze heard immunity against influenza viruses as well as severe course of influenza infection prior to the 2019–2020 epidemic season. Methods. Blood sera samples were collected prior to and after conducting population-wide influenza vaccination campaign at the sanitary and epidemiological centers in different regions of the Russian Federation as well as at the Siberian Federal District, respectively. Sera samples were tested by using hemagglutination inhibition (HI) assay with vaccine strains A/Brisbane/02/2018 (H1N1)pdm09, A/Kansas/14/2017 (H3N2), B/Colorado/06/2017 (Victoria lineage). Baseline clinical and autopsy materials in case of influenza infection in vaccinated patients or severe and fatal influenza cases were collected to be tested by RT-PCR at the sanitary and epidemiological centers, Rospotrebnadzor. All influenza-virus positive samples were further sent to the SRC VB “Vector”. Results. A total of 7,896 and 600 blood serum samples were collected from subjects at Siberian Federal District prior to and after the populationwide influenza vaccination campaign, respectively. Prior to the epidemic season, the proportion of individuals seropositive for the influenza A virus subtypes A/(H1N1)pdm09 and A/H3N2 exceeded 50% in most of the regions, whereas frequency of those seropositive for the influenza B virus was profoundly lower ranging from 12 to 46% in the Northwestern Federal District and Volga Federal District, respectively. After influenza vaccination, the percentage of seropositive subjects in the Siberian Federal District increased as follows: for influenza subtype A/(H1N1)pdm09 — from 66 up to 79%, influenza subtype A/H3N2 — from 68 up to 78%, and for influenza B/Victoria — from 32 up to 47%. In 2019–2020, influenza B virus more frequently caused severe infection that agrees with the herd immunity data prior to the epidemic season. However, the vast majority of the influenza cases with fatal outcome was associated with influenza virus A A/H1N1pdm09 subtype. Conclusion. Quality of influenza vaccine, especially that one intended to vaccinate risk group subjects remains a crucial issue for contemporary scientific community. The study was conducted within the framework of the State Assignments no. 1/16 and 2/18.</p></abstract><trans-abstract xml:lang="ru"><p>Цель работы — анализ популяционного иммунитета к гриппу накануне эпидемического сезона, а также тяжелых случаев заболевания в 2019–2020 гг. Методы. Образцы сывороток крови были собраны сотрудниками ЦГиЭ в субъектах Российской Федерации до проведения кампании по вакцинации населения от гриппа. После проведения вакцинации были собраны образцы сывороток в Сибирском ФО. Сыворотки тестировали в реакции торможения гемагглютинации (РТГА) с вакцинными штаммами A/Brisbane/02/2018 (H1N1)pdm09, A/Kansas/14/2017 (H3N2), B/Colorado/06/2017 (линия «Виктория»). Первичный клинический и аутопсийный материал в случаях заболевания вакцинированных, при летальных исходах гриппа и тяжелом течении болезни собирали и тестировали в ОТ-ПЦР сотрудники региональных центров гигиены и эпидемио логии Роспотребнадзора. Положительные образцы были переданы в ГНЦ ВБ «Вектор». Результаты. Всего было исследовано 7896 образцов сывороток крови, собранных до вакцинации населения, и 600 образцов, собранных в Сибирском ФО после вакцинации. Накануне эпидемического сезона количество положительных образцов к вирусу гриппа А субтипов A/(H1N1)pdm09 и A/H3N2 в большинстве регионов было выше 50%. Количество положительных образцов к вирусу гриппа В было существенно ниже: от 12% в Северо-Западном ФО до 46% в Приволжском ФО. После проведения вакцинации населения количество положительных образцов в Сибирском ФО выросло с 66 до 79% по субтипу A/(H1N1)pdm09, с 68 до 76% по субтипу A/H3N2, с 32 до 47% в случае вируса гриппа В/Виктория. В 2019–2020 гг. тяжелое заболевание чаще вызывал вирус гриппа В, что согласуется с данными о популяционном иммунитете накануне эпидемии. Однако смертельные исходы в подавляющем числе случаев были вызваны вирусом гриппа А субтипа A/H1N1pdm09. Заключение. Качество гриппозной вакцины, особенно предназначенной для групп риска, остается актуальной проблемой современной науки. Исследование проводилось в рамках выполнения государственного задания ГЗ-3/21 и ГЗ-2/21.</p></trans-abstract><kwd-group xml:lang="en"><kwd>influenza virus</kwd><kwd>herd immunity</kwd><kwd>hemagglutination inhibition test</kwd><kwd>antibody protective titers</kwd><kwd>severe influenza</kwd><kwd>influenza death rate</kwd><kwd>risk groups</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>вирус гриппа</kwd><kwd>популяционный иммунитет</kwd><kwd>реакция торможения гемагглютинации</kwd><kwd>защитные титры антител</kwd><kwd>тяжелое заболевание</kwd><kwd>смертность от гриппа</kwd><kwd>группы риска</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Авторы выражают глубокую благодарность коллегам из центров гигиены и эпидемиологии субъектов РФ за сбор и своевременную и качественную доставку в ГНЦ ВБ «Вектор» клинических образцов.</funding-statement></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>1. 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