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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.2021-6.1.5</article-id><article-id custom-type="elpub" pub-id-type="custom">actabiomedica-2608</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>КЛИНИЧЕСКАЯ ЛАБОРАТОРНАЯ ДИАГНОСТИКА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>CLINICAL LABORATORY DIAGNOSIS</subject></subj-group></article-categories><title-group><article-title>Вирусная нагрузка при COVID-19: недооценённый клинический и эпидемиологический маркер</article-title><trans-title-group xml:lang="en"><trans-title>Viral Load in COVID-19: Underestimated Clinical and Epidemiological Marker</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2169-0242</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Орлова</surname><given-names>Е. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Orlova</surname><given-names>E. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Орлова Елизавета Андреевна – младший научный сотрудник лаборатории эпидемиологически и социально-значимых инфекций, аспирант</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Elizaveta A. Orlova – Junior Research Officer at the Laboratory of Epidemic and Socially Significant Infections, Postgraduate</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">elizaveta.a.orlova@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3168-1983</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Огарков</surname><given-names>О. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Ogarkov</surname><given-names>O. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Огарков Олег Борисович – доктор медицинских наук, заведующий отделом эпидемиологии и микробиологии </p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Oleg B. Ogarkov – Dr. Sc. (Med.), Head of the Department of Epidemiology and Microbiology</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">obogarkov@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/0000-0001-7160-9700</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Жданова</surname><given-names>С. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Zhdanova</surname><given-names>S. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Жданова Светлана Николаевна – доктор медицинских наук, старший научный сотрудник лаборатории эпидемиологически и социально-значимых инфекций</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Svetlana N. Zhdanova – Dr. Sc. (Med.), Senior Research Officer at the Laboratory of Epidemic and Socially Significant Infections</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">svetnii@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/0000-0002-6449-5060</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Хромова</surname><given-names>П. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Khromova</surname><given-names>P. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Хромова Полина Андреевна – младший научный сотрудник лаборатории эпидемиологически и социально-значимых инфекций</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Polina A. Khromova – Junior Research Officer at the Laboratory of Epidemic and Socially Significant Infections</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">olina.and38@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3396-9590</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Синьков</surname><given-names>В. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Sinkov</surname><given-names>V. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Синьков Вячеслав Владимирович – кандидат медицинских наук, старший научный сотрудник лаборатории эпидемиологически и социально-значимых инфекций</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Vyacheslav V. Sinkov – Cand. Sc. (Med.), Senior Research Officer at the Laboratory of Epidemic and Socially Significant Infections</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">vsinkov@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8441-3640</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Хаснатинов</surname><given-names>М. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Khasnatinov</surname><given-names>M. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Хаснатинов Максим Анатольевич – доктор биологических наук, ведущий научный сотрудник лаборатории трансмиссивных инфекций</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Maksim A. Khasnatinov – Dr. Sc. (Biol.), Leading Research Officer at the Laboratory of Arthropod-Borne Infections</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">khasnatinov@yandex.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/0000-0002-0117-2563</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Рычкова</surname><given-names>Л. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Rychkova</surname><given-names>L. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Рычкова Любовь Владимировна – доктор медицинских наук, член-корреспондент РАН, профессор РАН, директор</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Lyubov V. Rychkova – Dr. Sc. (Med.), Corresponding Member of the RAS, Professor of the RAS, Director</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">iphr@sbamsr.irk.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/0000-0003-3354-2992</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Колесникова</surname><given-names>Л. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Kolesnikova</surname><given-names>L. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Колесникова Любовь Ильинична – доктор медицинских наук, профессор, академик РАН, научный руководитель</p><p>664003, г. Иркутск, ул. Тимирязева, 16</p></bio><bio xml:lang="en"><p>Lyubov I. Kolesnikova – Dr. Sc. (Med.), Professor, Academician of the RAS, Scientific Advisor</p><p>Timiryazeva str. 16, Irkutsk 664003</p></bio><email xlink:type="simple">iphr@sbamsr.irk.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБНУ «Научный центр проблем здоровья семьи и репродукции человека»</institution></aff><aff xml:lang="en"><institution>Scientific Centre for Family Health and Human Reproduction Problems</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2021</year></pub-date><pub-date pub-type="epub"><day>08</day><month>04</month><year>2021</year></pub-date><volume>6</volume><issue>1</issue><fpage>33</fpage><lpage>39</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Орлова Е.А., Огарков О.Б., Жданова С.Н., Хромова П.А., Синьков В.В., Хаснатинов М.А., Рычкова Л.В., Колесникова Л.И., 2021</copyright-statement><copyright-year>2021</copyright-year><copyright-holder xml:lang="ru">Орлова Е.А., Огарков О.Б., Жданова С.Н., Хромова П.А., Синьков В.В., Хаснатинов М.А., Рычкова Л.В., Колесникова Л.И.</copyright-holder><copyright-holder xml:lang="en">Orlova E.A., Ogarkov O.B., Zhdanova S.N., Khromova P.A., Sinkov V.V., Khasnatinov M.A., Rychkova L.A., Kolesnikova L.I.</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/2608">https://www.actabiomedica.ru/jour/article/view/2608</self-uri><abstract><sec><title>Обоснование</title><p>Обоснование. Вирусная нагрузка SARS-CoV-2, возбудителя новой коронавирусной инфекции, приобретает всё большее значение в клиническом и эпидемиологическом контекстах. Несмотря на это, существуют значительные ограничения во внедрении количественного измерения вирусной нагрузки в клиническую практику.</p><p>Цель данной работы заключалась в разработке подхода для количественной оценки вирусной нагрузки SARS-CoV-2 по значению пороговых циклов образца (Ct) относительно Ct внутреннего контрольного образца, получаемых в ходе рутинной лабораторной ПЦР-диагностики вируса, и в его использовании для мониторинга вирусной нагрузки среди первично выявленных пациентов из Иркутской области.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. С использованием регрессионных моделей на основе метода наименьших квадратов разработан подход для определения количества копий РНК SARS-CoV-2 в 1 мл носоглоточного секрета. Проведён мониторинг вирусной нагрузки SARS-CoV-2 в образцах носоглотки и зева, полученных от 1370 пациентов из гг. Иркутск и Ангарск с первично диагностированным положительным ПЦРрезультатом в период с 1 июля по 10 ноября 2020 г.</p></sec><sec><title>Результаты</title><p>Результаты. Выявлено десятикратное увеличение среднемесячной вирусной нагрузки среди пациентов в сентябре-октябре 2020 г. Мы предполагаем, что изменение эпидемиологической модели распространения новой коронавирусной инфекции в этот период ассоциировано с повышением количества контактов в популяции, связанным с началом учебного года. Более высокая вирусная нагрузка наблюдается в группах риска по COVID-19 – среди медицинских работников и взрослых/пожилых пациентов.</p></sec><sec><title>Заключение</title><p>Заключение. Разработка стандартизованного количественного определения вирусной нагрузки SARSCoV-2 в мазке может служить прогностическим клиническим маркером и надёжным инструментом для совершенствования эпиднадзора за COVID-19 при использовании предложенного подхода по оценке средней вирусной нагрузки в географически ограниченной популяции.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Background</title><p>Background. The viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the new coronavirus infection, is becoming increasingly important in clinical and epidemiological contexts. Despite this, there are significant complexities in the implementation of viral load quantitative measurement into clinical practice due to the limited approaches to its assessment.</p><p>The aim of this work was to develop an approach for SARS-CoV-2 viral load analysis by the value of sample threshold cycles (Ct) relative to the Ct of the internal control sample obtained in routine PCR diagnostics of the COVID-19, and to use this approach for quantitative monitoring of viral load in patients with first positive SARS-CoV-2 test from the Irkutsk region.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. Using regression models based on the least squares method, an approach to determine the number of copies of SARS-CoV-2 RNA in 1 ml of nasopharyngeal secretion was developed. The viral load of SARS-CoV-2 was assessed in nasopharyngeal and pharyngeal samples obtained from 1370 patients from Irkutsk and Angarsk with primary diagnosed positive PCR result in the period from July 1 to November 10, 2020.</p></sec><sec><title>Results</title><p>Results. A tenfold increase in the average monthly viral load among patients in September-October 2020 was revealed. We assume that the change in the epidemiological pattern of the spread of the new coronavirus infection during this period is associated with an increase in the number of contacts in the population due to the school year beginning. Higher viral loads are observed in populations at risk for COVID-19 – among healthcare workers and adults/elderly patients. </p></sec><sec><title>Conclusion</title><p>Conclusion. The development of a standardized quantification of SARS-CoV-2 viral load in the nasopharyngeal samples can be a predictive clinical marker and a reliable tool for improving COVID-19 surveillance using the proposed approach to assess average viral load in a local population.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>COVID-19</kwd><kwd>SARS-CoV-2</kwd><kwd>вирусная нагрузка</kwd><kwd>количественная ПЦР</kwd><kwd>пороговое число циклов</kwd></kwd-group><kwd-group xml:lang="en"><kwd>COVID-19</kwd><kwd>SARS-CoV-2</kwd><kwd>viral load</kwd><kwd>qPCR</kwd><kwd>cycle threshold</kwd><kwd>Ct</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Исследование выполнено в рамках НИР «Исследование особенностей эпидемического процесса социально значимых и возвращающихся инфекций в Северной Азии»   (АААА-А18-118051190033-0).</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Wu F, Zhao S, Yu B, Chen YM, Wang W, Song ZG, et al. 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