Sheffield study shows single Pfizer dose generates strong immune response against Covid

The research, led by the University of Oxford and the University of Sheffield, tested 237 healthcare workers for T-cell and antibody responses and discovered a “robust” reaction in 99 per cent of them.

It also found people who had previously been infected with Covid-19 showed higher T-cell and antibody responses after one dose of the Pfizer vaccine compared with people who had a first dose without contracting coronavirus before.

The researchers said the in-depth study, carried out between December 9 and February 9, suggested a single dose of Pfizer protected against severe disease, although it is unknown how long the protection lasts.

They added that protection levels were even stronger after a second dose of the vaccine and urged those who have had their first dose to return for the second.

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