Fully vaccinated people are three times less likely to test positive for Covid-19 than people who are unvaccinated, according to a Government-commissioned study.
The latest REACT-1 trial from Imperial College London and Ipsos MORI showed the percentage of those who tested positive for Covid-19 was 0.4% among double jabbed patients compared with 1.21% among those unvaccinated.
More than 98,000 volunteers took part in the latest study in England between 24 June and 12 July to examine the levels of Covid-19 across the general population.
It found double-vaccinated people had around 50% to 60% reduced risk of infection, including asymptomatic infection, compared to unvaccinated people.
Analysis by Imperial College suggested double vaccinated people are also less likely to pass on the virus to others.
But the latest data also shows infections in England have increased fourfold from 0.15% to 0.63% since the last REACT-1 report which covered the period 20 May to 7 June.
Professor Paul Elliott, director of the REACT programme from Imperial’s School of Public Health, said: ‘These findings confirm our previous data showing that both doses of a vaccine offer good protection against getting infected.
‘However we can also see that there is still a risk of infection, as no vaccine is 100% effective, and we know that some double vaccinated people can still become ill from the virus.
‘So even with the easing of restrictions, we should still act with caution to help protect one another and curb the rate of infections.’
Data from Public Health England shows that vaccines are highly effective against all variants of the virus.
The Pfizer/BioNTech vaccine is 96% effective and the Oxford/AstraZeneca vaccine is 92% effective against hospitalisation after both doses.
PHE estimates that the vaccination programme in England has prevented 22 million infections, around 52,600 hospitalisations and between 35,200 and 60,000 deaths.
Health secretary Sajid Javid said: ‘Our vaccination rollout is building a wall of defence that means we can carefully ease restrictions and get back to the things we love, but we need to be cautious as we learn to live with this virus.
‘Today’s report shows the importance of taking personal responsibility by self-isolating if you are contact traced, getting tested if you have symptoms and wearing face coverings where appropriate.
‘I urge anyone who has yet to receive a vaccine to get jabbed and take up both doses – the vaccines are safe and they are working.’