Vaccination is highly effective at preventing severe cases of Covid-19, even against the Delta variant, a vast study in France has shown.

The research — focusing on prevention of severe Covid and death, not infection — looked at 22 million people over 50 and found those who had received jabs were 90 per cent less likely to be hospitalised or die, according to AFP.

The study covers vaccination with the Pfizer/BioNtech, Moderna and AstraZeneca jabs, but not Jannsen which was authorised much later and is far less widely used in France.