Authors' reply to the letters concerning the article "Effectiveness of the BNT162b2 vaccine in preventing COVID-19-associated deaths in Poland".

INTRODUCTION Development of vaccines was a turning point of the COVID -19 pandemic. In this study, we describe the course of the vaccination program in Poland and the effectiveness of the BNT162b2 vaccine.OBJECTIVE The aim of the study was to analyze the vaccination rates and effectiveness stratified by age groups in Poland.PATIENTS AND METHODS This is a retrospective study based on the data on the vaccination rate and survival status among Polish citizens, obtained from the registries kept by the Polish Ministry of Health, the Statistics Poland, and the European Centre for Disease Prevention and Control. The data were collected between week 53 of 2020 and week 3 of 2022. The final analysis included patients who were either not vaccinated at all or fully vaccinated with the BNT162b2 vaccine.RESULTS The database contained records of 36 362 777 individuals, of whom 14 441 506 (39.71%) were fully vaccinated with the BNT162b2 vaccine and 14 220 548 (39.11%) were not vaccinated at all. The weekly average effectiveness of the BNT162b2 vaccine in preventing death was 92.62% and varied from 89.08% for the citizens aged 80 years and older, to 100% for individuals aged 5 to 17 years. The estimated mortality rate was significantly higher in the unvaccinated group than in the fully vaccinated group in the entire cohort (447.9 per 100 000 vs 43.76 per 100 000; P <0.001) in all age categories. CONCLUSIONS The study results confirm high effectiveness of the BNT162b2 vaccine in preventing COVID -19 deaths in all analyzed age groups.