Kuchma, M., Volianskyi, A., Yudin , I. , Davydova, T. and Kuchma, I. 2021. Features of the formation of immune layers of the population to SARS-CoV-2 in the Kharkov region for the period May-November 2020. Vaccination strategies. Annals of Mechnikov’s Institute. 3 (Sep. 2021), 21–28.