From 8 December 2020 to the end of March 2021, over 15 million vaccine doses were given to adults aged 60 and over. The analysis compared the observed number of deaths with the number of deaths that would have been expected if the vaccine hadn’t been given during this time period. To allow for the time taken to develop an immune response to vaccination, the analysis assumed it would take 31 days before the effect of vaccination on deaths is observed.
Using this method, PHE estimates that around 10,400 deaths were prevented to the end of March – 9,100 in those aged 80 and over, 1,200 in those aged 70 to 79 and 100 in those aged 60 to 69.
Expected deaths with coronavirus (COVID-19) were estimated using real-world data on how effective the vaccines are at preventing death and vaccine uptake.
This analysis takes into account the direct effects of vaccines, there is now increasing evidence that vaccines help to reduce transmission, therefore it is likely that an even higher number of deaths will have been prevented by the vaccination programme.
The PHE analysis estimated the impact of the vaccination programme by combining data on vaccine effectiveness against mortality and the vaccine coverage. Observed deaths were then adjusted by the impact to estimate the daily expected deaths in the absence of vaccination.
Vaccine effectiveness against mortality was based on the most recent PHE estimates of effectiveness of vaccination against symptomatic infection (58%) and of death given infection (54%) which combined gives 81% protection against death.
In order to allow for the time taken to develop an immune response to vaccination and for a mortality endpoint, we assumed it would take 31 days before the effect of vaccination on deaths is observed.
The calculation was done in the 60 to 69, 70 to 79, and over 80 year olds separately. The overall total is cumulated across all days until 31 March 2021 and across the 3 years age groups.
Up until and including the 31 March, over 13 million first doses of vaccine and over 2 million second doses of vaccine were given to those aged 60 and over.