Many reports on the impact of vaccination on COVID-19 pandemic deaths were projections undertaken as the global emergency was unfolding. An increasing number of independent investigators have drawn attention to the subjective nature and inherent biases in mathematical models used for such forecasts that could undermine their accuracy when excess mortality was the metric of choice.
Objective
COVID-19 deaths were compared between the pre-vaccines and vaccination eras to observe how vaccination impacted COVID-19 death trajectory worldwide during the pandemic emergency.
Methods
COVID-19 cases, deaths and vaccination rates in World Health Organization (WHO) database till 07 June 2023, Case fatality rate per 1000 for the pre-vaccines period (CFR1), and that over vaccination era (CFR2) were compared for all WHO regions, while tests of correlation between the percentage change in COVID-19 deaths and variables of interest were examined.
Results
COVID-19 deaths increased with vaccination coverage ranging from 43.3% (Africa) to 1275.0% (Western Pacific). The Western Pacific (1.5%) and Africa (3.8%) regions contributed least to the global cumulative COVID-19 deaths pre-vaccines, while the Americas (49.9%) and Europe (27.6%) had the highest counts. The Americas (39.8%) and Europe (34.1%) accounted for >70% of global COVID-19 deaths despite high vaccination, and the percentage increase in COVID-19 mortality and the percentage of person’s ≥65 years were significantly correlated (0.48) in Africa.
Conclusion
COVID-19 mortality increased in the vaccination era, especially in regions with higher vaccination coverage.
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