PECULIARITIES OF SARS-COV-2 NUCLEOCAPSID IN CHILDREN DURING THE COVID-19 EPIDEMIC OF 2020
Authors:   Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being, Moscow, Russia, Popova A.Yu. , Andreeva E.E. ,   Rospotrebnadzor Administration in Moscow, Moscow, Russia, Babura E.A. ,   Rospotrebnadzor Administration in the Kaliningrad Region, Kaliningrad, Russia, Balakhonov S.V. ,   Irkutsk Anti-Plague Research Institute of Siberia and the Far East, Irkutsk, Russia, Bashketova N.S. ,   Rospotrebnadzor Administration in St. Petersburg, St. Petersburg, Russia, Bugorkova S.A. ,   Russian Research Anti-Plague Institute «Microbe», Saratov, Russia, Bulanov M.V. ,   Center for Hygiene and Epidemiology in the Vladimir Region, Vladimir, Russia, Valeullina N.N. ,   Rospotrebnadzor Administration in the Chelyabinsk region, Chelyabinsk, Russia, Goryaev D.V. ,   Rospotrebnadzor Administration in the Krasnoyarsk Territory, Krasnoyarsk, Russia, Detkovskaya N.N. ,   Rospotrebnadzor Administration in the Primorsky Krai, Vladivostok, Russia, Ezhlova E.B. ,   Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being, Moscow, Russia, Zaitseva N.N. ,   Academician I.N. Blokhina Nizhny Novgorod Scientific Research Institute of Epidemiology and Microbiology, Nizhny Novgorod, Russia, Istorik O.A. ,   Rospotrebnadzor Administration in the Leningrad Region, St. Petersburg, Russia, Kovalchuk I.V. ,   Rospotrebnadzor Administration in the Stavropol Territory, Stavropol, Russia, Kozlovskikh D.N. ,   Rospotrebnadzor Administration in the Sverdlovsk Region, Yekaterinburg, Russia, Kombarova S.Yu. ,   G.N. Gabrichevsky Moscow Scientific Research Institute of Epidemiology and Microbiology, Moscow, Russia, Kurganova O.P. ,   Rospotrebnadzor Administration in the Amur Region, Blagoveshchensk, Russia, Lomovtsev A.E. ,   Rospotrebnadzor Administration in the Tula Region, Tula, Russia, Lukicheva L.A. ,   Rospotrebnadzor Administration in the Murmansk region, Murmansk, Russia, Lyalina L.V. ,   St. Petersburg Pasteur Institute of Epidemiology and Microbiology, St. Petersburg, Russia, Melnikova A.A. ,   Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being, Moscow, Russia, Mikailova O.M. ,   Rospotrebnadzor Administration in the Moscow Region, Mytishchi, Russia, Noskov A.K. ,   Rostov-on-Don Research Institute for Plague Control, Rostov-on-Don, Russia, Noskova L.N. ,   Rospotrebnadzor Administration for the Astrakhan region, Astrakhan, Russia, Oglezneva E.E. ,   Rospotrebnadzor Administration in the Belgorod Region, Belgorod, Russia, Osmolovskaya T.P. ,   Rospotrebnadzor Administration in the Krasnodar Territory, Krasnodar, Russia, Patyashina M.A. ,   Rospotrebnadzor Administration in the Republic of Tatarstan, Kazan, Russia, Penkovskaya N.A. ,   Rospotrebnadzor Administration in the Republic of Crimea, Simferopol, Ukraine, Samoilova L.V. ,   Rospotrebnadzor Administration in the Novosibirsk Region, Novosibirsk, Russia, Smirnov V.S. ,   St. Petersburg Pasteur Institute of Epidemiology and Microbiology, St. Petersburg, Russia, Stepanova T.F. ,   Tyumen Research Institute of Regional Infectious Pathology, Tyumen, Russia, Trotsenko O.E. ,   Khabarovsk Research Institute of Epidemiology and Microbiology, Khabarovsk, Russia, Totolian A.A. ,   St. Petersburg Pasteur Institute of Epidemiology and Microbiology, St. Petersburg, Russia
Published: May 2021

The aim of the study is to summarize the results of a study of seroprevalence of children to SARS-CoV-3, obtained during the implementation of the Rospotrebnadzor program to assess seroprevalence to the NC antigen SARS-CoV-2 of the population of 26 regions of the Russian Federation, conducted during the COVID-19 epidemic in 2020. Research methods: the study of seroprevalence in 26 model territories of the Russian Federation was carried out according to a unified methodology developed by Rospotrebnadzor with the participation of the St. Petersburg Pasteur Institute of Epidemiology and Microbiology. The method provided for the formation of a group of volunteers in a model federative entity, including children aged 1–17 years, in which the presence of antibodies to the SARS-CoV-2 nucleocapsid was determined in venous blood plasma by the enzyme-linked immunosorbent assay (ELISA). The examination of volunteers was carried out in 3 stages: June-August, September-October, December. Results: the study found that in most of the areas surveyed, children had a higher level of seroprevalence than adults. It is shown that high seroprevalence is accompanied by statistically significant decrease in morbidity (p0.05). The analysis of seroprevalence at all three stages revealed at least 3 variants of its dynamics: 1) continuous growth of seroprevalence in parallel with the development of the epidemic process; 2) an episodic change in the periods of increase and decrease in the level of seroprevalence; 3) a continuous decrease in seroprevalence at the level of the epidemic process. Comparative determination of seroconversion levels in three age groups – 1–6, 7–13 and 14–17 years – revealed no statistically significant differences between these age groups have been identified. Conclusion: children aged 1–17 years in most of the surveyed territories of the Russian Federation have a higher seroprevalence to SARS-CoV2 than adults. The increase in seroprevalence in children is accompanied by a decrease in the incidence of COVID-19.