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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="research-article" 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">17617</article-id><article-id pub-id-type="doi">10.15789/2220-7619-MGC-17617</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>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Molecular genetic characterization of hepatitis B virus in blood donors from South Vietnam</article-title><trans-title-group xml:lang="ru"><trans-title>Молекулярно-генетическая характеристика вируса гепатита B у доноров крови из Южного Вьетнама</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Ostankova</surname><given-names>Yu. V.</given-names></name><name xml:lang="ru"><surname>Останкова</surname><given-names>Ю. В.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Head of the Laboratory of immunology and Virology HIV Infection, Senior Researcher of the Laboratory of Molecular Immunology</p></bio><bio xml:lang="ru"><p>к.б.н., зав. лабораторией иммунологии и вирусологии ВИЧ-инфекции, старший научный сотрудник лаборатории молекулярной иммунологии</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Huynh</surname><given-names>H.K.T.</given-names></name><name xml:lang="ru"><surname>Хуинх</surname><given-names>Х.К.Т.</given-names></name></name-alternatives><address><country country="VN">Viet Nam</country></address><bio xml:lang="en"><p>Researcher, Medical Analysis Laboratory Department</p></bio><bio xml:lang="ru"><p>научный сотрудник лаборатории медицинских анализов</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Serikova</surname><given-names>E. N.</given-names></name><name xml:lang="ru"><surname>Серикова</surname><given-names>Е. Н.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Researcher, Laboratory of Immunology and Virology of HIV Infection</p></bio><bio xml:lang="ru"><p>научный сотрудник лаборатории иммунологии и вирусологии ВИЧ-инфекции</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Schemelev</surname><given-names>A. N.</given-names></name><name xml:lang="ru"><surname>Щемелев</surname><given-names>А. Н.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Junior Researcher, Laboratory of Immunology and Virology of HIV Infection</p></bio><bio xml:lang="ru"><p>младший научный сотрудник лаборатории иммунологии и вирусологии ВИЧ-инфекции</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Reingardt</surname><given-names>D. E.</given-names></name><name xml:lang="ru"><surname>Рейнгардт</surname><given-names>Д. Э.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Doctor of Clinical Laboratory Diagnostic, Department of Diagnostics of HIV Infection and AIDS-related Diseases</p></bio><bio xml:lang="ru"><p>врач клинической лабораторной диагностики отделения ВИЧ-инфекции и СПИД-ассоциированных заболеваний</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Davydenko</surname><given-names>V. S.</given-names></name><name xml:lang="ru"><surname>Давыденко</surname><given-names>В. С.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Junior Researcher, Laboratory of Immunology and Virology of HIV Infection, PhD Student</p></bio><bio xml:lang="ru"><p>младший научный сотрудник лаборатории иммунологии и вирусологии ВИЧ-инфекции, аспирант</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Totolian</surname><given-names>A. A.</given-names></name><name xml:lang="ru"><surname>Тотолян</surname><given-names>А. А.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>RAS Full Member, PhD, MD (Medicine), Professor, Head of the Laboratory of Molecular Immunology, Director; Head of the Department of Immunology</p></bio><bio xml:lang="ru"><p>академик РАН, д.м.н., профессор, зав. лабораторией молекулярной иммунологии, директор; зав. кафедрой иммунологии</p></bio><email>shenna1@yandex.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">St. Petersburg Pasteur Institute</institution></aff><aff><institution xml:lang="ru">ФБУН НИИ эпидемиологии и микробиологии имени Пастера</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Ho Chi Minh Pasteur Institute</institution></aff><aff><institution xml:lang="ru">Институт имени Пастера в г. Хошимин</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2024-05-20" publication-format="electronic"><day>20</day><month>05</month><year>2024</year></pub-date><pub-date date-type="pub" iso-8601-date="2024-06-05" publication-format="electronic"><day>05</day><month>06</month><year>2024</year></pub-date><volume>14</volume><issue>2</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>320</fpage><lpage>330</lpage><history><date date-type="received" iso-8601-date="2024-03-06"><day>06</day><month>03</month><year>2024</year></date><date date-type="accepted" iso-8601-date="2024-05-15"><day>15</day><month>05</month><year>2024</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2024, Ostankova Y.V., Huynh H., Serikova E.N., Schemelev A.N., Reingardt D.E., Davydenko V.S., Totolian A.A.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2024, Останкова Ю.В., Хуинх Х., Серикова Е.Н., Щемелев А.Н., Рейнгардт Д.Э., Давыденко В.С., Тотолян А.А.</copyright-statement><copyright-year>2024</copyright-year><copyright-holder xml:lang="en">Ostankova Y.V., Huynh H., Serikova E.N., Schemelev A.N., Reingardt D.E., Davydenko V.S., Totolian A.A.</copyright-holder><copyright-holder xml:lang="ru">Останкова Ю.В., Хуинх Х., Серикова Е.Н., Щемелев А.Н., Рейнгардт Д.Э., Давыденко В.С., Тотолян А.А.</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/17617">https://iimmun.ru/iimm/article/view/17617</self-uri><abstract xml:lang="en"><p>The problem of transfusion safety preventing parenteral viral hepatitis transmission remains relevant. Viral hepatitis B (HB) is the most common viral infection transmitted through transfusion procedures. One of the natural phases of a chronic viral hepatitis B (CHB) course is occult hepatitis B infection (OBI) characterized by undetectable HBsAg level (regardless of other serological marker levels) along with detected hepatic HBV DNA as well as blood viral load ranging from extremely low to undetectable. In Vietnam, prevention of transfusion-based HBV transmission is focused on donor screening; it is still based solely on HBsAg serology. As such, OBI remains a potential threat to blood transfusion safety. Assessing hepatitis B virus (HBV) DNA is a reliable preventive measure against HBV transmission from HBsAg– donors, especially in highly endemic regions. The aim of our work was HBV identification and molecular genetic characterization in blood donors from South Vietnam. The study material was presented by 500 donor serum samples. Subjects were examined for HBV markers with qualitative detection of HBsAg, HBs IgG, and HBcore IgG. Amplification and subsequent HBV sequencing were performed using nested PCR with overlapping primer pairs jointly flanking the complete HBV genome (S, P, C, X genes). Full-size HBV genome nucleotide sequences were obtained for 58 samples. Among blood donors, taking into account HBsAg+ and HBsAg– samples, HBV DNA was detected in 11.6%, including 8.6% OBI. HBV phylogenetic analysis showed genotypes B and C. Vaccine escape mutations and mutations that contribute to disease progression were identified. Current screening in Vietnam is insufficient for eliminating the risk of transfusion-transmitted HBV infection. The major risk factor is OBI. PCR testing for HBV should be considered for blood donor screening.</p></abstract><trans-abstract xml:lang="ru"><p>Проблема инфекционной безопасности переливания крови с целью предупреждения передачи вирусов гепатитов является актуальной медицинской проблемой. Вирусный гепатит В (ГВ) остается наиболее распространенной вирусной инфекцией, передающейся при переливании крови. Одной из естественных фаз течения хронического вирусного гепатита В (ХГВ) является скрытый гепатит В (СкГВ), характеризующийся неопределяемым уровнем HBsAg (независимо от содержания других серологических маркеров) при наличии ДНК вируса в ткани печени, а также вирусной нагрузкой в крови, варьирующей от крайне низкой до необнаруживаемой. Вьетнаме профилактика трансфузионной передачи вируса гепатита В (ВГВ) сосредоточена на скрининге доноров, который по-прежнему основан только на выявлении HBsAg. Таким образом, СкГВ остается потенциальной угрозой безопасности переливания крови. Определение ДНК ВГВ является надежной профилактической мерой против передачи вируса от доноров с HBsAg– ГВ, особенно в высокоэндемичных регионах. Целью нашей работы была идентификация и молекулярно-генетическая характеристика ВГВ у доноров крови из Южного Вьетнама. Материалом для исследования послужили 500 образцов плазмы крови, полученных от доноров. Субъекты были обследованы на наличие серологических маркеров ГВ с качественным определением HBsAg, антител анти-HBs IgG и анти-HBcore IgG, а также молекулярно-биологического маркера — ДНК ВГВ. Амплификацию и последующее секвенирование генома ВГВ проводили с помощью гнездовой ПЦР с перекрывающимися парами праймеров, совместно фланкирующих полный геном HBV (гены S, P, C, X). Полные нуклеотидные последовательности генома HBV были получены для 58 образцов. Среди доноров крови, с учетом HBsAg+ и HBsAg– образцов, ДНК ВГВ была обнаружена в 11,6%, в том числе в 8,6% случаев СкГВ. Филогенетический анализ ВГВ показал наличие генотипов B и C. Были выявлены мутации, приводящие к иммунологическому ускользанию, и мутации, способствующие прогрессированию заболевания. Проводимый в настоящее время во Вьетнаме скрининг недостаточен для устранения риска трансфузионной передачи ВГВ-инфекции. Основным фактором риска является СкГВ, в связи с чем высокочувствительное ПЦР-тестирование на ВГВ следует рассматривать как дополнительный приоритетный метод для скрининга доноров крови.</p></trans-abstract><kwd-group xml:lang="en"><kwd>hepatitis B virus (HBV)</kwd><kwd>hepatitis B viral markers</kwd><kwd>HBsAg-negative hepatitis B</kwd><kwd>genotypes</kwd><kwd>clinically significant mutations</kwd><kwd>blood donors</kwd><kwd>infection safety</kwd><kwd>South Vietnam</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>вирус гепатита В (ВГВ)</kwd><kwd>маркеры вирусного гепатита В</kwd><kwd>HBsAg-негативный гепатит В</kwd><kwd>генотипы</kwd><kwd>клинически значимые мутации</kwd><kwd>доноры крови</kwd><kwd>инфекционная безопасность</kwd><kwd>Южный Вьетнам</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Бумбали С., Серикова Е.Н., Балде Т.А.Л., Останкова Ю.В., Щемелев А.Н., Валутите Д.Э., Зуева Е.Б., Семенов А.В., Тотолян Арег А. 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