Britons catching Covid-19 after being vaccinated get a far milder form of the disease, according to data from the King’s College symptoms tracker app.
The team at King’s said as the number of people being vaccinated increased, those reporting an infection after the jab was rising, but the symptoms had changed.
Prof Tim Spector, lead scientist on the ZOE Covid Study app, and professor of Genetic Epidemiology at King’s, said: “Whereas in the past about half of people had classic symptoms in the first week, less than a third do now, if they've had a vaccination.
“And so you're gonna get less symptoms, they'll be less severe, they won't be classic, so do keep an open mind and do get a test when we ask you to, that way we'll keep a close eye on it, and make sure that even if mild, you're not going to pass it on to other people.
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“The importance of our survey is getting even greater because the disease is shifting. The fact that we haven't relied on those three symptoms like official government ones allows us much more breadth to find out what's really going on, and whether not only the new various might be causing different symptoms.”
A third of UK adults are now fully vaccinated against Covid-19, latest figures have shown. A total of 17,669,379 people have received both jabs, the equivalent of 33.5 per cent of all people aged 18 and over.
Meanwhile, 35,371,669 people in the UK have now received a first dose of vaccine, the equivalent of 67.2 per cent of the adult population.
King’s estimates the current risk of a Covid-19 infection for the unvaccinated is one in 46,855, falling to 1 in 97,616 after the first dose, and 1 in 167,341 after the second dose.
Infection rates are at the lowest level since September, and hospital admissions and patients in hospital continue to decrease, or plateau at low levels in some areas, with levels similar to July last year.
ONS estimates show that 1 in 1,180 people have Covid-19, down from 1 in 480 at the start of April.
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