Over the past three months, the critically-ill have been 49 on average, compared with 59 in the second wave of the pandemic.

Around half of those admitted to intensive care units are under 50, and nearly one third under 40.

The NHS figures illustrate the dramatic success of vaccines in protecting older adults, almost all of whom have been double-jabbed.

Wards are instead filling up with those most likely to be unvaccinated, including young adults, pregnant women and people from black or deprived communities.