Evaluation of the Effectiveness of Immunization Saint-Petersburg Population against COVID-19

Relevance. Vaccination is being replaced by the primary and most effective means of protecting the world's population from a new coronavirus infection.

Aim. Evaluation of the effectiveness of COVID-19 immunization in Saint-Petersburg.

Materials and methods: We retrospectively studied the epidemiological data on the cumulative incidence of COVID-19 in St. Petersburg among adults vaccinated (1,558,030 people) and unvaccinated (2,863,050 people) for period from December 01, 2020 to November 30, 2021 on 12.01.2021. We analyzed the data presented in the Federal Register of Persons with COVID-19 and the Federal Register of Those Vaccinated against COVID-19.

Results. The risk of COVID-19 infection among vaccinated is statistically significantly lower than among unvaccinated RR = 0.11 (95% CI 0.109–0.110; p < 0.001). Infected COVID-19 Vaccinated patients were less likely to need for emergency care/hospitalization RR = 0.30 (95% CI 0.29–0.30; p < 0.001). Also among the vaccinated mortality was lower RR = 0.35 (95% CI 0.33–0.37; p < 0.001).

Conclusion: We have established reliable preventive effectiveness of the use of domestic vaccines by reducing morbidity, the frequency of development of forms of the disease requiring inpatient treatment; reducing mortality among vaccinated and, accordingly, reducing the burden on the healthcare system of St. Petersburg.

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