A French study has shown that the Pfizer/BioNTech, Moderna and AstraZeneca vaccines are highly effective on the older half of the population aged 59-75, providing up to 92% protection against the virulent Delta variant of Covid-19. For those aged 75 and older the protective effect was estimated at 84%.
Starting 14 days after a second dose, a vaccinated subjects' risk of severe Covid was reduced by 90 per cent, according to the research conducted by Epi-Phare, an independent medicines safety research group that works closes with the French government.
The study authors claim that it is the largest study of its size to date, with over 11 million participants. Each vaccinated participant was paired with an unvaccinated individual of the same age and sex and from the same region and was tracked over the period of time from the second vaccination. The study began in December 2020 as France initiated its public vaccination programme.
However, the authors cautioned that the results should be taken with a grain of salt as the Delta variant only began appearing later during the course of the study and so this may be a limitation to the accuracy of their results. The results also suggest that over the period of study - up to five months - vaccination protection against severe Covid did not diminish.