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<article article-type="research-article" dtd-version="1.3" 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" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">actabiomedica</journal-id><journal-title-group><journal-title xml:lang="ru">Acta Biomedica Scientifica</journal-title><trans-title-group xml:lang="en"><trans-title>Acta Biomedica Scientifica</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2541-9420</issn><issn pub-type="epub">2587-9596</issn><publisher><publisher-name>Scientific Centre for Family Health and Human Reproduction Problems</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.29413/ABS.2020-5.5.3</article-id><article-id custom-type="elpub" pub-id-type="custom">actabiomedica-2436</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ИНФЕКЦИОННЫЕ БОЛЕЗНИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>INFECTIOUS DISEASES</subject></subj-group></article-categories><title-group><article-title>Изучение гуморального иммунного ответа при лёгкой и бессимптомной формах проявления COVID-19</article-title><trans-title-group xml:lang="en"><trans-title>Studying Humoral Immune Response at Mild and Asymptomatic COVID-19 Forms</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4201-5828</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Балахонов</surname><given-names>С. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Balakhonov</surname><given-names>S. V.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">balakhonov.irk@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8561-6207</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Дубровина</surname><given-names>В. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Dubrovina</surname><given-names>V. I.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">dubrovina-valya@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5489-9363</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Чеснокова</surname><given-names>М. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Chesnokova</surname><given-names>M. V.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">adm@chumin.irkutsk.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0685-7625</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Войткова</surname><given-names>В. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Voitkova</surname><given-names>V. V.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">vvoitkova@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6381-4517</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Пятидесятникова</surname><given-names>А. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Pyatidesyatnikova</surname><given-names>A. B.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">smy_irkutsk@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5589-9522</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Брюхова</surname><given-names>Д. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Bryukhova</surname><given-names>D. D.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">darabrukhov@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-6678-2998</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Киселева</surname><given-names>Н. О.</given-names></name><name name-style="western" xml:lang="en"><surname>Kiseleva</surname><given-names>N. O.</given-names></name></name-alternatives><bio xml:lang="ru"/><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">smy_irkutsk@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-1137-6049</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Корытов</surname><given-names>К. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Korytov</surname><given-names>K. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>научный сотрудник лаборатории патофизиологии</p><p>664047, г. Иркутск, ул. Трилиссера, 78, Россия</p></bio><bio xml:lang="en"><p>Trilissera str. 78, Irkutsk 664047, Russian Federation </p></bio><email xlink:type="simple">konstmikhkor@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кузнецова</surname><given-names>Т. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Kuznetsova</surname><given-names>T. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p>заместитель главного врача по организационно-методической работе</p><p>666904, Иркутская область, г. Бодайбо, ул. 30 лет Победы, 6, Россия</p></bio><bio xml:lang="en"><p>30 let Pobedy str. 6, Bodaybo 666904, Irkutsk Region, Russian Federation </p></bio><email xlink:type="simple">adm@chumin.irkutsk.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Маркевич</surname><given-names>Ж. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Markevich</surname><given-names>Zh. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>заместитель главного врача по лечебной работе</p><p>666904, Иркутская область, г. Бодайбо, ул. 30 лет Победы, 6, Россия</p></bio><bio xml:lang="en"><p>30 let Pobedy str. 6, Bodaybo 666904, Irkutsk Region, Russian Federation </p></bio><email xlink:type="simple">adm@chumin.irkutsk.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФКУЗ Иркутский научно-исследовательский противочумный институт Сибири и Дальнего Востока Федеральной службы по надзору в сфере защиты прав потребителей и благополучия человека</institution></aff><aff xml:lang="en"><institution>Irkutsk Antiplague Research Institute of Siberia and Far East of Rospotrebnadzor</institution></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ОГБУЗ «Районная больница г. Бодайбо»</institution></aff><aff xml:lang="en"><institution>Bodaybo District Hospital</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2020</year></pub-date><pub-date pub-type="epub"><day>06</day><month>11</month><year>2020</year></pub-date><volume>5</volume><issue>5</issue><fpage>26</fpage><lpage>30</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Балахонов С.В., Дубровина В.И., Чеснокова М.В., Войткова В.В., Пятидесятникова А.Б., Брюхова Д.Д., Киселева Н.О., Корытов К.М., Кузнецова Т.Г., Маркевич Ж.В., 2020</copyright-statement><copyright-year>2020</copyright-year><copyright-holder xml:lang="ru">Балахонов С.В., Дубровина В.И., Чеснокова М.В., Войткова В.В., Пятидесятникова А.Б., Брюхова Д.Д., Киселева Н.О., Корытов К.М., Кузнецова Т.Г., Маркевич Ж.В.</copyright-holder><copyright-holder xml:lang="en">Balakhonov S.V., Dubrovina V.I., Chesnokova M.V., Voitkova V.V., Pyatidesyatnikova A.B., Bryukhova D.D., Kiseleva N.O., Korytov K.M., Kuznetsova T.G., Markevich Z.V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.actabiomedica.ru/jour/article/view/2436">https://www.actabiomedica.ru/jour/article/view/2436</self-uri><abstract><sec><title>Актуальность</title><p>Актуальность. В настоящее время в условиях пандемии COVID-19 одной из наиболее актуальных задач здравоохранения является обеспечение безопасности населения Российской Федерации. Сведений о длительности и напряжённости постинфекционного иммунитета в отношении SARS-CoV-2 собрано недостаточно, особенно при инаппарантных (без клинических признаков), лёгких или стёртых формах проявления инфекции.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. В исследовании приняли участие 99 добровольцев c  лабораторно подтверждённым методом ПЦР диагнозом COVID-19 – прибывшие на работу в г. Бодайбо вахтовым методом жители Иркутской области и других регионов Российской Федерации, а также 50 условно здоровых лиц, проживающих в г. Иркутске и имеющих  на момент обследования отрицательные результаты ПЦР на наличие РНК SARS-CoV-2.Специфические антитела IgG и IgM к SARS-CoV-2 определяли в сыворотке крови  методом иммуноферментного анализа (ИФА) с использованием тест-систем «ИФА анти- SARS-CoV-2 IgG» (ФБУН ГНЦ ПМБ, г. Оболенск), «SARS-CoV-2-IgG-ИФА-БЕСТ» и «SARS-CoV-2-IgM-ИФА-БЕСТ» (АО «Вектор-Бест», г. Новосибирск).</p></sec><sec><title>Результаты</title><p>Результаты. Представлены результаты исследования гуморального иммунитета  пациентов с бессимптомной и манифестной формами проявления COVID-19. Полученные данные свидетельствуют о выработке специфических IgG в сыворотке крови людей на 2–3-й неделях после инфицирования вирусом SARS-Cov-2 и достижении их максимального уровня на 20–21-й день болезни. Показатель сероконверсии составил 94,9 %. Показано, что среднегеометрический титр антител при бессимптомной и лёгкой формах проявления коронавирусной инфекции статистически не различался и  составлял 1:512 и 1:632 соответственно. Более высокие титры антител (1:1600) выявляли при среднетяжелой форме.</p></sec><sec><title>Заключение</title><p>Заключение. Результаты исследований могут послужить основой для изучения динамики изменений показателей гуморального иммунного ответа у переболевших COVID-19 и выяснения длительности их постинфекционного иммунитета с целью прогнозирования развития эпидемической ситуации и обеспечения планирования  специфической профилактики. </p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Background</title><p>Background. Currently, during the COVID-19 pandemic, one of the most pressing healthcare problems is to ensure the safety of the population of the Russian Federation. There is insufficient information on the duration and intensity of post-infectious immunity in relation to SARS-CoV-2, especially in case of inapparent (without clinical signs), mild or latent forms of infection.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The study involved 99 volunteers with a laboratory confirmed PCR diagnosis of COVID-19 who were residents of the Irkutsk Region and of other regions of the Russian Federation and arrived to work in Bodaybo on a rotational basis. Also the study included 50 conditionally healthy people living in Irkutsk who had negative PCR results for SARS-CoV-2 RNA presence.Specific IgG and IgM antibodies to SARS-CoV-2 were detected in blood serum by enzyme-linked immunosorbent assay (ELISA) using test systems “ELISA anti-SARS-CoV-2 IgG” (FBUN SSC PMB, Obolensk, Russian Federation), “SARS-CoV-2-IgG-IFA-BEST” and “SARS-CoV-2-IgM-IFA-BEST” (Vector-Best, Novosibirsk, Russian Federation).</p></sec><sec><title>Results</title><p>Results. The results of a study of the humoral immunity of patients with asymptomatic and clinical forms of COVID-19 are presented. The data indicate the production of specific IgG in the blood serum of people in 2–3 weeks after SARSCov-2 infection and reaching its maximum level on the 20–21st day. The seroconversion rate  was 94.9 %. It was shown that the geometric mean titer of antibodies in asymptomatic and mild forms of coronavirus infection did not differ statistically and amounted to 1:512 and 1:632, respectively. Higher titers of antibodies (1:1600) were detected in the moderate form.</p></sec><sec><title>Conclusion</title><p>Conclusion. The research results can serve as a basis for studying the dynamics of changes in the indicators  of the humoral immune response in patients with COVID-19 and for clarifying the duration of their post- infectious immunity in order to predict the development of the epidemic situation and to ensure the planning of specific prevention. </p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>гуморальный иммунитет</kwd><kwd>специфические антитела</kwd><kwd>COVID-19</kwd><kwd>SARS-CoV-2</kwd></kwd-group><kwd-group xml:lang="en"><kwd>humoral immunity</kwd><kwd>specific antibodies</kwd><kwd>COVID-19</kwd><kwd>SARS-CoV-2</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Кутырев В.В., Попова А.Ю., Смоленский И.Ю., Ежлова Е.Б., Демина Ю.В., Сафронов В.А., и др. Эпидемиологические особенности новой коронавирусной инфекции (Сovid-19). 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