UK data shows Pfizer-BioNTech vaccination provides high levels of protection from the first dose

'One dose reduces risk of catching infection by more than 70%'

Early data from PHE’s SIREN study shows a promising impact on infection in healthcare workers aged under 65. Healthcare workers in the study are tested for coronavirus (COVID-19) every 2 weeks – whether or not they have symptoms.

Data shows one dose reduces the risk of catching infection by more than 70%, rising to 85% after the second dose. This suggests the vaccine may also help to interrupt virus transmission, as you cannot spread the virus if you do not have infection.

PHE’s analysis of routine testing data also shows that one dose is 57% effective against symptomatic COVID-19 disease in those aged over 80. This effect occurs from about 3 to 4 weeks after the first dose.

Early data suggests the second dose in over 80s improves protection against symptomatic disease by a further 30%, to more than 85%.

'Far less likely to die or be hospitalised'

Hospitalisation and deaths rates are falling in all age groups – but the oldest age groups are seeing the fastest decline since the peak in mid-January.

Early data suggests vaccinated people who go on to become infected are far less likely to die or be hospitalised. Overall, hospitalisation and death from COVID-19 will be reduced by over 75% in those who have received a dose of the Pfizer-BioNTech vaccine.

The risk of dying in those aged over 80 is less than half (56%) in vaccinated cases compared to unvaccinated cases, at least 14 days after receiving the first dose.

'PHE will continue to observe these trends'

Those over 80 who develop COVID-19 infection after vaccination are around 40% less likely to be hospitalised than someone with infection who has not been vaccinated.

These high levels of protection are also seen against the variant of concern (B.1.1.7) first identified in South East England in December 2020.

While the data on infection, hospitalisation and death is promising, PHE will continue to observe these trends closely over the coming months to ensure firmer conclusions can be made.

PHE is also monitoring the real-world impact of the AstraZeneca vaccine and will publish these findings in due course – but early signals in the data suggest it’s providing good levels of protection from the first dose.