Over the last four months, the Rockefeller team’s findings have been repeatedly observed in real life. People who have recovered from a Covid-19 infection in the past, and then been vaccinated, appear to be more resilient to the new variants, from Delta to Omicron.

Immunologists have taken blood samples from these individuals and found them to have a kind of “super immunity” – dubbed hybrid immunity by the scientific world. These people produce not only astronomically high levels of antibodies – far more than those who have just been double vaccinated and boosted – but a much more diverse range of antibodies, which have a greater chance of finding viral weak spots, even in a highly mutated form of Covid-19.

A recent study from scientists in Boston and South Africa found that people who had been previously infected with a form of Covid-19, before having two vaccine doses and a booster, had greater immunity against Omicron – the closest thing in real life to Rockefeller’s artificial virus.

“Once people who have had Covid-19 are vaccinated with an mRNA vaccine, you see that they produce an antibody response which is three times higher than those who received the vaccine without prior infection,” says Nussenzweig.