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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">epidemiology</journal-id><journal-title-group><journal-title xml:lang="ru">Эпидемиология и Вакцинопрофилактика</journal-title><trans-title-group xml:lang="en"><trans-title>Epidemiology and Vaccinal Prevention</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2073-3046</issn><issn pub-type="epub">2619-0494</issn><publisher><publisher-name>«Numicom» LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.31631/2073-3046-2021-20-5-39-51</article-id><article-id custom-type="elpub" pub-id-type="custom">epidemiology-1362</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>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group></article-categories><title-group><article-title>Изучение уровня и структуры популяционного иммунитета к SARS-CoV2 у населения Республики Татарстан в период второго пика распространения COVID-19</article-title><trans-title-group xml:lang="en"><trans-title>Study of the Level and Structure of Population Immunity to SARS-CoV2 in the Population of the Republic of Tatarstan during the Second Peak of the Spread of COVID-19</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4890-1812</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Садыков</surname><given-names>М. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Sadykov</surname><given-names>M. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Марат Наилевич Садыков – к. м. н., министр</p></bio><bio xml:lang="en"><p>Marat N. Sadykov  – Cand. Sci. (Med.), health minister</p><p>Kazan</p></bio><email xlink:type="simple">Sadykov.Marat@tatar.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/0000-0001-8029-6515</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Зиатдинов</surname><given-names>В. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Ziatdinov</surname><given-names>V. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Васил Билалович Зиатдинов  – д. м. н., директор</p></bio><bio xml:lang="en"><p>Vasil B. Ziatdinov – Dr. Sci. (Med.), head</p><p>Kazan</p></bio><email xlink:type="simple">kniem@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3584-6861</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Решетникова</surname><given-names>И. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Reshetnikova</surname><given-names>I. D.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Ирина Дмитриевна Решетникова  – к. м. н., доцент; заместитель директора по  научной работе, доцент кафедры фундаментальных основ клинической медицины</p></bio><bio xml:lang="en"><p>Irina D. Reshetnikova – Cand. Sci. (Med.), Deputy Head; Associate Professor</p><p>Kazan</p></bio><email xlink:type="simple">reshira@mail.ru</email><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7895-0012</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Хакимов</surname><given-names>Н. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Khakimov</surname><given-names>N. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Нияз Маратович Хакимов  – к. м. н., доцент кафедры эпидемиологии и доказательной медицины</p></bio><bio xml:lang="en"><p>Niyaz M. Khakimov – Cand. Sci. (Med.), Associate Professor at the Department of Epidemiology and Evidence-Based Medicine </p><p>Kazan</p></bio><email xlink:type="simple">hakimniaz@gmail.com</email><xref ref-type="aff" rid="aff-4"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8896-969X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Лопушов</surname><given-names>Д. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Lopushov</surname><given-names>D. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Дмитрий Владимирович Лопушов – к. м. н., доцент кафедры профилактической медицины и экологии человека; доцент кафедры эпидемиологии и дезинфектологии</p></bio><bio xml:lang="en"><p>Dmitriy V. Lopushov – Cand. Sci. (Med.), Associate Professor at the Department of Preventive Medicine and Human Ecology; Associate Professor at the Department of Epidemiology and Disinfectology</p><p>Kazan</p></bio><email xlink:type="simple">doctor225@mail.ru</email><xref ref-type="aff" rid="aff-5"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1462-8734</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Исаева</surname><given-names>Г. Ш.</given-names></name><name name-style="western" xml:lang="en"><surname>Isaeva</surname><given-names>G. Sh.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Гузель Шавхатовна Исаева – д. м. н., профессор, заместитель директора по инновационному развитию; заведующая кафедрой микробиологии имени академика В. М. Аристовского</p></bio><bio xml:lang="en"><p>Guzel Sh. Isaeva – Dr. Sci. (Med.), Professor, Deputy Director for InnovativeDevelopment; Head of the Department of Microbiology named after Academician V.M. Aristovsky</p><p>Kazan</p></bio><email xlink:type="simple">kniem@mail.ru</email><xref ref-type="aff" rid="aff-6"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Министерство здравоохранения Республики Татарстан<country>Россия</country></aff><aff xml:lang="en">Ministry of Health of the Republic of Tatаrstan<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">ФБУН «Казанский НИИ эпидемиологии и микробиологии» Роспотребнадзора<country>Россия</country></aff><aff xml:lang="en">Kazan Scientific Research Institute of Epidemiology and Microbiology<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru">ФБУН «Казанский НИИ эпидемиологии и микробиологии» Роспотребнадзора; ИФМиБ ФГАОУ ВО «Казанский (Приволжский) федеральный университет<country>Россия</country></aff><aff xml:lang="en">Kazan Scientific Research Institute of Epidemiology and Microbiology; Kazan Federal University<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru">ФГБОУ ВО «Казанский государственный медицинский университет»<country>Россия</country></aff><aff xml:lang="en">Kazan State Medical University<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-5"><aff xml:lang="ru">ФГБОУ ВО «Казанский государственный медицинский университет; Казанская государственная медицинская академия – филиал ГБОУ ДПО РМАНПО Минздрава России<country>Россия</country></aff><aff xml:lang="en">Kazan State Medical University; Kazan medical academy<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-6"><aff xml:lang="ru">ФБУН «Казанский НИИ эпидемиологии и микробиологии» Роспотребнадзора; ФГБОУ ВО «Казанский государственный медицинский университет»<country>Россия</country></aff><aff xml:lang="en">Kazan Scientific Research Institute of Epidemiology and Microbiology; Kazan State Medical University<country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>03</day><month>11</month><year>2021</year></pub-date><volume>20</volume><issue>5</issue><fpage>39</fpage><lpage>51</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Садыков М.Н., Зиатдинов В.Б., Решетникова И.Д., Хакимов Н.М., Лопушов Д.В., Исаева Г.Ш., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Садыков М.Н., Зиатдинов В.Б., Решетникова И.Д., Хакимов Н.М., Лопушов Д.В., Исаева Г.Ш.</copyright-holder><copyright-holder xml:lang="en">Sadykov M.N., Ziatdinov V.B., Reshetnikova I.D., Khakimov N.M., Lopushov D.V., Isaeva G.S.</copyright-holder><license 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.epidemvac.ru/jour/article/view/1362">https://www.epidemvac.ru/jour/article/view/1362</self-uri><abstract><sec><title>Актуальность</title><p>Актуальность. Пандемия COVID-19 стала серьезным вызовом для всего человечества в связи со стремительным глобальным распространением, высокой частотой развития тяжелых форм, повышенной летальностью и потребовала разработки новых подходов к управлению эпидемиологическим процессом. Важнейшим инструментом для мониторинга инфекционного процесса, выявления групп риска, оценки действия используемых вакцин и эпидемиологических прогнозов являются серологические исследования.</p></sec><sec><title>Цель</title><p>Цель. Проведение серологического исследования для выявления случаев перенесенной новой коронавирусной инфекции, определения уровня и структуры популяционного иммунитета к SARS-CoV-2 у населения Республики Татарстан в период распространения COVID-19 – с августа по декабрь 2020 г.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. В исследовании приняли участие 41 444 жителя Республики Татарстан, заполнивших анкеты, включавшие клинические, анамнестические данные и эпидемиологический анамнез в отношении COVID-19. Участники прошли тестирование на наличие IgG, IgA и IgM) к коронавирусу SARS-CoV-2 методом усиленной хемилюминесценции на анализаторе VITROS 3600 с использованием тест-систем VITROS Anti-SARS-CoV-2 Total Reagent Pack. Статистическую обработку проводили с использованием методов вариационной статистики с помощью статистического пакета Exсel и программного продукта «WinPepi» (версия 11.65).</p></sec><sec><title>Результаты</title><p>Результаты. Доля серопозитивных к SARSCoV- 2 среди населения Республики Татарстан составила в среднем 35,8 ± 0,235% с нарастанием от 29,95 ± 0,674% (в августе) до 68 ±9,33% (в декабре). Наибольшая доля серопозитивных лиц выявлена в группе трудоспособного населения в возрасте 18–59 лет. Среднее геометрическое антител составило 4,2 (4,09–4,31), среди серопозитивных – 89,29 (88,13–90,46). В социально-профессиональной структуре населения наибольшая доля серопозитивных лиц выявлена среди работников производства 40,35 ± 2,177, творческих профессий – 40 ± 9,798; здравоохранения – 35,24 ± 0,389; неработающих – 34,26 ± 1,218 и госслужащих – 33,06 ± 2,479. Среди серопозитивных к вирусу SARS-CoV-2 жителей Республики Татарстан доля бессимптомной форм инфекции составила 82,59 ± 0, 446%.</p></sec><sec><title>Вывод</title><p>Вывод. Наблюдается позитивная динамика серопозитивности среди населения Республики Татарстан. Проведение сероэпидемиологического мониторинга дает возможность прогнозировать развитие эпидемиологической ситуации, планировать мероприятия специфической и неспецифической профилактики COVID19.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Background</title><p>Background. The COVID-19 pandemic has become a serious challenge for all of humanity due to the rapid global spread, high frequency of severe forms, increased mortality and required the development of new approaches to managing epidemiological processes. Serological studies are the most important tool for monitoring the infectious process, identifying risk groups, assessing the effect of vaccines used and epidemiological projections.</p></sec><sec><title>Purpose</title><p>Purpose. Conducting serological monitoring in relation to the modern transferred new coronavirus infection determining the level and structure of population immunity to SARS-CoV-2 in the population of the Republic of Tatarstan; maintaining the period of spread of COVID-19 from August to December 2020.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The study involved 41 444 residents of the Republic of Tatarstan, who filled out questionnaires that included clinical, anamnestic data and an epidemiological history in relation to COVID-19, who were tested for the presence of common antibodies (IgG, IgA and IgM) to the SARS coronavirus. CoV-2 by the method of enhanced chemiluminescence on the VITROS 3600 analyzer using the VITROS Anti-SARS-CoV-2 Total Reagent Pack test systems.</p><p>Statistical processing was carried out by methods of variation statistics and correlation analysis according to the Pearson method using MS Excel and WinPepi.</p></sec><sec><title>Results</title><p>Results. Seropositivity to SARSCoV-2 in the population of the Republic of Tatarstan averaged 35.8 ± 0.235%. An increase in the level of seropositive persons was noted from 29.95 ± 0.674% in August to 68 ± 9.33% in December. The highest proportion of seropositive individuals was found in was found in the group of the able-bodied population aged 18–59 years. The average geometric titer of antibodies was 4.2 (4.09–4.31), among seropositive – 89.29 (88.13–90.46). In the social and professional structure of the population, the largest proportion of seropositive individuals was found in was found among production workers 40.35 ± 2.177, creative professions – 40 ± 9.798; health care 35.24 ± 0.389; 34.26 ± 1.218 unemployed and 33.06 ± 2.479 civil servants. Among the residents of the Republic of Tatarstan, seropositive to the SARS-CoV-2 virus, the proportion of asymptomatic forms of infection was 82.59 ± 0.446%.</p></sec><sec><title>Сonclusions</title><p>Сonclusions. There is a positive dynamics of seropositivity among the population of the Republic of Tatarstan. The results of sero-epidemiological monitoring can be used to predict the epidemiological situation, plan measures for specific and non-specific prophylaxis of COVID19.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>COVID-19</kwd><kwd>серопозитивность к SARS-CoV- 2</kwd><kwd>население</kwd><kwd>Республика Татарстан</kwd><kwd>серологический мониторинг</kwd><kwd>популяционный иммунитет</kwd></kwd-group><kwd-group xml:lang="en"><kwd>SARS-CoV-2</kwd><kwd>COVID-19</kwd><kwd>seropositivity</kwd><kwd>population</kwd><kwd>Republic of Tatarstan</kwd><kwd>serological monitoring</kwd><kwd>population immunity No conflict of interest to declare</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">Sethuraman N., Jeremiah SS., Ryo A. Interpreting Diagnostic Tests for SARS-CoV-2. JAMA. 2020 May 6. 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