Some aspects of specific prevention of a new coronavirus infection caused by the SARS CoV-2 virus in the Samara region

The new coronavirus infection remains a significant medical and social event in the world, and only active immunization of the population with the achievement of the target level of vaccination coverage of at least 60% is able to stop its spread.

Objective: to study the preliminary results of vaccination against a new coronavirus infection caused by the SARS CoV-2 virus in the Samara region.

Materials and methods. The material of this study was the results of statistical monitoring of the incidence of a new coronavirus infection caused by the SARS CoV-2 virus in residents of the Samara region and data on the vaccination campaign. Statistical analysis included descriptive, comparative and interval estimation, as well as correlation analysis.

Results. As of October 2022, 62.6% of the total population in the Samara region has been vaccinated against a new coronavirus infection caused by the SARS CoV-2 virus. Women predominated among those vaccinated – 60.51%. When analyzing the results of the vaccination campaign, statistically significant negative relationships were revealed between the proportion of vaccinated in a certain month and the incidence in the next three months, as well as between the accumulated percentage of vaccinated and the incidence in the next few months. At the same time, morbidity and vaccination in a normalized form for the population does not depend on the size of the population.

Conclusions: Vaccination reduces the risk of a new coronavirus infection caused by the SARS CoV-2 virus in the Samara region by an average of 7.4 times. With the development of a manifest form of a new coronavirus infection caused by the SARS CoV-2 virus, in residents of the Samara region who have undergone a full course of vaccination, the risk of developing severe and extremely severe forms decreases by an average of 1.65 times, and deaths – by 1.71 times.

1. WHO Interim Recommendations "Principles of implementation and adjustment of measures to protect public health and social measures in connection with the spread of COVID-19" June 14, 2021. (In Russ). https://apps.who.int/iris/bitstream/handle/10665/341811/WHO-2019-nCoV-Adjusting-PH-measures-2021.1-rus.pdf

2. Khan S., Ali A., Siddique R., Nabi G. Novel coronavirus is putting the whole world on alert. J Hosp Infect. 2020 Mar;104(3):252–253. https://doi.org/10.1016/j.jhin.2020.01.019

3. Yu Shi, Gang Wang, Xiao-peng Cai, Jing-wen Deng, Lin Zheng, et al. An overview of COVID-19. Journal of Zhejiang University SCIENCE B. 2020;21(5):343–360. http://doi.org/10.1631/jzus.B2000083

4. Reports of the Communication Center of the Government of the Russian Federation on the situation with coronavirus. (In Russ). https://стопкоронавирус.рф/info/ofdoc/reports/

5. Reports of the Operational Headquarters of the Samara region on the situation with coronavirus. (In Russ). https://www.samregion.ru/institutions/aktualnye-temy-dlya-grazhdan-regiona/stop_covid_2019/novosti/

6. Sana O Alturki, Sawsan O Alturki, Jennifer Connors, Gina Cusimano, Michele A Kutzler, Abdullah M Izmirly et al. The 2020 Pandemic: Current SARS-CoV-2 Vaccine Development. Front Immunol. 08,2020;11:1880; PMID: 32973779. http://doi.org/10.3389/fimmu.2020.01880

7. Doroftei Bogdan, Ciobica Alin, Ilie Ovidiu-Dumitru, Maftei Radu and Ilea Ciprian. Mini-Review Discussing the Reliability and Efficiency of COVID-19 Vaccines. Diagnostics. 2021;11(4):579. https://doi.org/10.3390/diagnostics11040579

8. Logunov Denis Y, Dolzhikova Inna V, Shcheblyakov Dmitry V, Tukhvatulin Amir I, Zubkova Olga V, Dzharullaeva Alina S et al. Safety and efficacy of an rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 vaccine: an interim analysis of a randomised controlled phase 3 trial in Russia. Lancet. 02, 2021;397:671–681. https://doi.org/10.1016/S0140-6736(21)00234-8

9. Ryzhikov A.B., Ryzhikov E.A., Bagryantseva M.P., Usova S.V., Danilenko E.D., Nechaeva E.A., etc. A simple blind placebo-controlled randomized study of the safety, reactogenicity and immunogenicity of the EpiVacCorona vaccine for the prevention of COVID-19 on volunteers aged 18-60 years (phase I–II). Infection and immunity. 2021;11(2):283–296. (In Russ). https://doi.org/10.15789/2220-7619-ASB-1699

10. Kozlovskaya L.I., Pinaeva A.N., Ignatiev G.M., Gordeychuk I.V., Volok V.P., Rogova Yu.V., etc. Long-term humoral immunogenicity, safety and protective efficacy of inactivated COVID-19 vaccine (CoviVac) in preclinical studies. New germs and infections. 2021;10(1):1790–1806. (In Russ). https://www.tandfonline.com/doi/full/10.1080/22221751.2021.1971569

11. Stephen J. Thomas, Edson D. Moreira, Nicholas Kitchin, Judith Absalon, Alejandra Gurtman, Stephen Lockhart et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine through 6 Months. N Engl J Med. 2021;385:1761–1773. https://doi.org/10.1056/NEJMoa2110345

12. Katherine R W Emary, Tanya Golubchik, Parvinder K Aley, Cristina V Ariani, Brian Angus, Sagida Bibi et al. Efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 variant of concern 202012/01 (B.1.1.7): an exploratory analysis of a randomised controlled trial. Lancet. 2021;397:1351–1362.https://doi.org/10.1016/S0140-6736(21)00628-0

13. Paul T. Heath, Eva P. Galiza, David N. Baxter, Marta Boffito, Duncan Browne, Fiona Burns et al. Safety and Efficacy of NVX-CoV2373 Covid-19 Vaccine. N Engl J Med. 2021;385:1172–1183. https://doi.org/10.1056/NEJMoa2107659

14. Jerald Sadoff, Glenda Gray, An Vandebosch, Vicky Cárdenas, Georgi Shukarev, Beatriz Grinsztejn et al. Safety and Efficacy of Single-Dose Ad26.COV2.S Vaccine against Covid-19. N Engl J Med. 2021;384:2187–2201. https://doi.org/10.1056/NEJMoa2101544

15. Nawal Al Kaabi, Yuntao Zhang, Shengli Xia et al. Effect of 2 Inactivated SARS-CoV-2 Vaccines on Symptomatic COVID-19 Infection in Adults. A Randomized Clinical Trial. JamaNetwork. 2021;May 12. https://doi.org/10.1001/jama.2021.8565

16. Susan M Bueno, Katia Abarca, Pablo A González, Nicolás Ms Gálvez, Jorge A Soto, Luisa F Duarte et al. Interim report: Safety and immunogenicity of an inactivated vaccine against SARS-CoV-2 in healthy chilean adults in a phase 3 clinical trial. MedRxiv. 2021 Apr 1;2021.03.31.21254494; PMID: 35441164; https://doi.org/10.1101/2021.03.31.21254494

17. Bilev A.E., Sokurova A.M., Bileva N.A., Kachkovskii M.A., Vvedenskaya I.P. Russian vaccines against COVID-19: their characteristics, efficacy and safety. Bulletin of the Medical Institute "REAVIZ" (REHABILITATION, DOCTOR AND HEALTH). 2022;12(6):6-14. (In Russ). https://doi.org/10.20340/vmi-rvz.2022.6.COVID.1]

18. Lindsey R. Baden, Hana M. El Sahly, Brandon Essink, Karen Kotloff, Sharon Frey, Rick Novak et al. Efficacy and Safety of the mRNA-1273 SARS-CoV-2 Vaccine. N Engl J Med. 2021;384:403–416. https://doi.org/10.1056/NEJMoa2035389

19. Temporary guidelines: prevention, diagnosis and treatment of new coronavirus infection (COVID-19) version 16 (08/18/2022). (In Russ). https://static-0.minzdrav.gov.ru/system/attachments/attaches/000/060/193/original/ВМР_COVID-19_V16.pdf