The influenza epidemic in Russia during the 2014–2015 season

The goal of this study was to compare the data on the intensity of the influenza A(H3N2) and B epidemic (especially the death toll) in the 2014–2015 season with the previous epidemic of the 2013-2014 season. The data on weekly morbidity, hospitalization, deaths from influenza, and acute respiratory diseases in different age groups of inhabitants of 59 cities located in 7 Federal districts of the Russian Federation were collected using the database of the Research Institute of Influenza.Analysis of this data showed that the influenza epidemic in 2014-2015 began earlier (in December) compared to the epidemic of 2013-2014, and spread mainly from Europe through Russia to the East. The intensity of the epidemic of 2014-2015 was higher compared to the previous one. The epidemic was more prevalent by regions and cities and a wider engagement of different age groups (except children up to 2 years of age) was observed. At the peak of the epidemic, the morbidity level was higher, the average duration of the epidemic was longer, and the number of patients among cities’ inhabitants (especially among children 7-14 years of age and adults) was higher than in the previous season. The rates of hospitalization with influenza and acute respiratory viral infections (ARVI) among patients older than 65 years were also higher (1.4 times) as well as the frequency of hospitalization with a diagnosis of “influenza” (2.7 times) and the number of deaths from laboratory confirmed influenza (1.8 times).Although the influenza pandemic virus strain A(H1N1)pdm09 was not the main causative agent of the 2015 epidemic and was distributed sporadically it still remained the leading cause of deaths from influenza in the course of this epidemic (45.5% of all cases). The deaths associated with this strain were recorded only in the European part of Russian Federation.The goal of this study was to compare the data on the intensity of the influenza A(H3N2) and B epidemic (especially the death toll) in the 2014–2015 season with the previous epidemic of the 2013-2014 season. The data on weekly morbidity, hospitalization, deaths from influenza, and acute respiratory diseases in different age groups of inhabitants of 59 cities located in 7 Federal districts of the Russian Federation were collected using the database of the Research Institute of Influenza. Analysis of this data showed that the influenza epidemic in 2014-2015 began earlier (in December) compared to the epidemic of 2013-2014, and spread mainly from Europe through Russia to the East. The intensity of the epidemic of 2014-2015 was higher compared to the previous one. The epidemic was more prevalent by regions and cities and a wider engagement of different age groups (except children up to 2 years of age) was observed. At the peak of the epidemic, the morbidity level was higher, the average duration of the epidemic was longer, and the number of patients among cities’ inhabitants (especially among children 7-14 years of age and adults) was higher than in the previous season. The rates of hospitalization with influenza and acute respiratory viral infections (ARVI) among patients older than 65 years were also higher (1.4 times) as well as the frequency of hospitalization with a diagnosis of “influenza” (2.7 times) and the number of deaths from laboratory confirmed influenza (1.8 times). Although the influenza pandemic virus strain A(H1N1)pdm09 was not the main causative agent of the 2015 epidemic and was distributed sporadically it still remained the leading cause of deaths from influenza in the course of this epidemic (45.5% of all cases). The deaths associated with this strain were recorded only in the European part of Russian Federation

Эпидемия гриппа в России в сезон 2014–2015 гг.

The goal of this study was to compare the data on the intensity of the influenza A(H3N2) and B epidemic (especially the death toll) in 2014–2015 season with the previous epidemic of 2013-2014. The data on weekly morbidity, hospitalization, deaths from influenza and acute respiratory diseases in different age groups of inhabitants of 59 cities located in 7 Federal districts of the Russian Federation were collected using the database of the Research Institute of Influenza. Analysis of this data showed, that the influenza epidemic in 2014-2015 began earlier (in December), compared with the epidemic of 2013-2014, and spread mainly from Europe through Russia to the East. The intensity of the epidemic 2014-2015 was higher, compared to the previous one. The epidemic was more prevalent by regions and cities and wider engagement of different age groups (except children up to 2 years) was observed. At the peak of the epidemic the morbidity level was higher, the average duration of the epidemic was longer and the number of patients among cities inhabitants (especially among children 7-14 years of age and adults) was higher than in the previous season. The rates of hospitalization with influenza and ARI among patients older than 65 years were also higher (1.4 times) as well as frequency of hospitalization with a diagnosis of “influenza” (2.7 times) and the number of deaths from laboratory confirmed influenza (1.8 times). Although the pandemic influenza virus A(H1N1)pdm09, was not the main causative agent of the epidemic 2015, it still was the main cause of deaths from influenza (45.5% of all cases). In spite of influenza A(H1N1)pdm09 virus sporadic prevalence, deaths from it were reported only on the European part of territory of Russia.Целью работы было сравнение показателей интенсивности эпидемии гриппа, вызванной штаммами вирусов гриппа А(H3N2) и В, в сезон 2014–2015 гг. с предшествующей эпидемией 2013–2014 гг. Особое внимание уделено летальным исходам от гриппа. Использована база данных НИИ гриппа по еженедельной заболеваемости, госпитализации, летальным исходам от гриппа и ОРЗ в различных возрастных группах населения 59-ти наблюдаемых городов, расположенных в семи Федеральных округах Российской Федерации. По сравнению с эпидемией 2014 г. эпидемия гриппа в 2014–2015 гг. началась раньше (в декабре) и распространялась, в основном, с запада на восток – из Европы по территории России в восточном направлении. Показатели интенсивности эпидемии 2015 г., в сравнении с предыдущей, были выше в отношении распространенности по округам, городам и вовлеченности возрастных групп населения (кроме детей до 2-х лет). Показатели заболеваемости на пике эпидемии, средней продолжительности эпидемии, уровней заболеваемости населения в городах (особенно среди детей 7–14 лет и взрослого населения) были выше, чем в предыдущем сезоне. Участились и случаи госпитализации с гриппом и OPВИ среди лиц старше 65 лет (в 1.4 раза), среди госпитализированных повысилась доля больных с диагнозом «грипп» (в 2.7 раза) и число летальных исходов от лабораторно подтвержденного гриппа (в 1.8 раза). Штамм пандемического вируса гриппа, A(H1N1)pdm09, хотя и не был основным возбудителем эпидемии 2015 г., попрежнему стал основной причиной летальных исходов от гриппа (в 45.5% всех случаев); причем случаи смерти, ассоциированные с этим штаммом, регистрировали только на европейской территории России при спорадическом уровне его распространения

Peculiarities of the influenza viruses circulation and their properties during 2018-2019 epidemic season in Russia and countries of the Northern Hemisphere

Objective. To identify the drift variability of influenza viruses during the period of epidemic rise in the incidence of acute respiratory viral infections in the period 2018-2019. The biological and molecular-genetic properties of epidemic strains isolated in certain territories of the Russian Federation were studied and compared with data from the countries of the Northern Hemisphere. Materials and methods. A range of laboratory diagnostic methods has been applied, including immune fluorescence, RT-PCR, sequencing, methods for determining sensitivity to influenza drugs and receptor specificity. Results and discussion. The proportion of influenza viruses was as follows: A (H1N1) pdm09 - 53 %, A (H3N2) - 46 %, B - about 1 %. Cases of severe acute respiratory infections have most often been associated with influenza A(H1N1) pdm09 virus. According to antigenic properties, isolated strains corresponded to the properties of vaccine viruses (A/Michigan/45/2015 - by 99.6 % and A/Singapore INFIMH-16-0019/2016 - by 86 %). The heterogeneity of influenza A virus strains population was revealed as regards individual mutations in hemaglutinin. The influenza B virus population was equally represented by both evolutionary lines (B/Victoria and B/Yamagata-like). Receptor specificity was favorable for the course and outcome of the disease. Among 70 studied epidemic strains, no strains resistant to anti-neuraminidase drugs, oseltamivir and zanamivir, were detected. The article presents WHO recommendations on the composition of influenza vaccines for the countries of the Northern Hemisphere for 2019-2020, provides data on cases of human infection with avian influenza viruses A(H5N1), A(H5N6), A(H7N9) and A(H9N2)

Заболеваемость гриппом в январе-марте 2016 г. в Российской Федерации: эпидемический и пандемический потенциал вируса гриппа A(H1N1)pdm09

The World Health Organization (WHO) searches influenza virus circulation in community and in natural biocenosis, studies virus strains and their properties, develops diagnostic methods and preventive measures since 1940th worldwide because of epidemic actuality and high pandemic potential of the influenza virus. The Federal Influenza Center (including Federal Research Institute of Influenza, Saint-Petersburg, and the Center of Virus Ecology, D.I.Ivanovskiy Virology Institute, Honorary Academician N.F.GamaleyaFederal Research Center of Epidemiology and Microbiology, Federal Research Center for Epidemiology and Microbiology, Moscow) performs similar work in Russia in close cooperation with WHO within the framework of the International Programme of Influenza Monitoring. A(H1N1)pdm09 influenza virus dominated in the Northern Hemisphere in the 2015 – 2016 epidemic season. Morbidity growth was noted from the end of January, 2016, to the beginning of March, 2016. The peak morbidity at the 5th week of the year exceeded the epidemic threshold (132 cases per 10,000 of population) and morbidity in the 2014 – 2015 season significantly and approached to the peak morbidity of the 2009 – 2010 epidemic season. The epidemic growth in Russian Federation was provided by three influenza viruses: A(H1N1)pdm09, В and A (H3N2). A(H1N1)pdm09 virus caused 18% of all acute respiratory diseases and accounted for 84% of circulating influenza viruses.Flu was diagnosed in patients of different age with maximal frequency in 3- to 6-year old children. Peak admission number was registered at 5 and 6 weeks (3,538 and 4,109 cases, respectively); this number exceeded the similar parameter of the 2009 – 2010 season. Patients of 15 to 64 years old were admitted more often including those with acute respiratory infection. Two hundred and thirty nine deaths were registered to the 5th of April, 2016, according to data from the Federal Influenza Center and the Center of Virus Ecology. The diagnosis of A(H1N1)pdm09 flu was confirmed in 97.9% of deaths. Molecular analysis of isolated strains of A(H1N1)pdm09 influenza virus revealed amino acid substitutions in receptor binding site and SA site of hemagglutinin and in genes coding intrinsic proteins PA, NP, M1, and NS1. Influenza virus strains resistive to anti-neuraminidase drugs were encountered in #< 1% in the Northern Hemisphere countries. No strains studied were sensitive to adamantine derivates.Актуальность. С 1947 г. в связи с эпидемической актуальностью и высоким пандемическим потенциалом вируса гриппа типа А по инициативе Всемирной организации здравоохранения (ВОЗ) организована Глобальная система по надзору за гриппом и ответу (Global Influenza Surveillance and Response System – GISRS), которая в настоящее время представлена 6 сотрудничающими центрами по гриппу, 143 национальными центрами по гриппу в 113 странах, а также производителями гриппозных вакцин. Российская Федерация представлена в этой системе двумя национальными центрами – Федеральным центром по гриппу (ФЦГ) ФГБУ «Научно-исследовательский институт гриппа» Минздрава России (Санкт-Петербург) и Центром экологии и эпидемиологии гриппа (ЦЭЭГ) Института вирусологии им. Д.И.Ивановского ФГБУ «Федеральный научно-исследовательский центр эпидемиологии и микробиологии имени почетного академика Н.Ф.Гамалеи» Минздрава России (Москва). Оба центра осуществляют еженедельный надзор за циркуляцией вирусов гриппа в 59 городах Российской Федерации, который предполагает анализ заболеваемости, госпитализации, летальных случаев от гриппа и острой респираторной вирусной инфекции (ОРВИ) в разных возрастных группах, а также проведение диагностики с помощью широкого спектра лабораторных методов. Материалы и методы. В странах Северного полушария в эпидемическом сезоне 2015–2016 гг. в этиологии подъема заболеваемости доминировал вирус гриппа A(H1N1)pdm09. Подъем заболеваемости гриппом в России зарегистрирован с конца января до начала марта 2016 г. Показатель заболеваемости на пике эпидемии (5-я неделя 2016 г.), значительно превысив эпидемический порог (132 случая на 10 тыс. населения) и значение сезона 2014–2015 гг., отмечен на уровне эпидемического сезона 2009–2010 гг. Результаты. Этиологическую структуру эпидемического подъема заболеваемости в РФ определили 3 вируса гриппа – A(H1N1)pdm09, В и A(H3N2) при разном долевом участии. Грипп A(H1N1)pdm09 в структуре ОРВИ составила 18,0 %, в структуре циркулирующих вирусов гриппа – 84,0 %. Заболеваемость зарегистрирована во всех возрастных группах. Бόльшая вовлеченность в эпидемический процесс зафиксирована у детей 3–6 лет. Максимальное число госпитализаций отмечено на 5-й и 6-й неделях 2016 г. – 3 538 и 4 109 случаев соответственно, что превысило показатели сезона 2009–2010 гг. Наибольшее число случаев госпитализации, в т. ч. с тяжелой острой респираторной инфекцией, отмечено в возрастной группе 15–64 лет. По данным ФЦГ и ЦЭЭГ, на 05.04.16 зарегистрировано 239 летальных исходов. В 97,9 % случаев лабораторными исследованиями подтвержден грипп A(H1N1)pdm09. Заключение. По результатам молекулярно-генетического анализа выделенных штаммов вируса гриппа A / H1N1pdm09 показано наличие аминокислотных замен в гемагглютинине (рецептор-связывающем и Sa сайтах) и в генах, кодирующих внутренние белки (PA, NP, M1, NS1). Доля резистентных штаммов к препаратам с антинейраминидазной активностью в странах Северного полушария не превысила 1 %, а к производным адамантана оказались нечувствительными все изученные циркулирующие штаммы

Treatment of acute respiratory viral infections and influenza in children: the minimal sufficiency principle

Acute respiratory viral infections (ARVI) occupy a special place in pediatric practice. This is due to several factors including high incidence, increased morbidity, frequently severe course and risk of complications especially in children with premorbidities, as well as a significant economic and social burden [1]. It should be specifically noted that ARVI in children is the main reason for seeking medical care on an outpatient basis, accounting for more than 90% of all doctor visits during the epidemic outbreak of the disease [2]