For check-it-yourself statistical analysis of influenza vaccinations v Covid-19 death rates (Europe):
Dr Allan Cunningham's original proposal, extended to exponential fit: here;
Dr Grahame Blackwell's full extended analysis: detailed version or slightly abbreviated.

For Dr Blackwell's ground-breaking scientific research, giving radically new perspectives on time, matter and Relativity,
including books, presentations and published papers: (also includes contact link): Transfinite Mind.