Critics have warned that it is impossible to gauge the true impact that the virus is having on the NHS when the numbers are so skewed by “incidental Covid” cases.

The latest figures from the Office for National Statistics (ONS) show that one in 15 people are currently infected with the virus, making incidental cases more common than in previous waves.

However, some doctors argue that testing positive for Covid adds extra strain on the NHS because patients still need to be isolated even if they do not need treatment for the virus. 

In addition, experts have pointed out that true cases are continuing to rise. In England, the number of true Covid cases in hospital has risen by 47 per cent since Dec 28, while non-Covid cases included in the numbers have increased by 75 per cent.

Doctors feeling pressure of rising Covid cases

Prof Stephen Powis, the national medical director for NHS England, said rising Covid cases were “piling even more pressure” on hospital workers at a time of severe staff shortages and winter pressures.

“Omicron means more patients to treat and fewer staff to treat them,” he said. “In fact, around 10,000 more colleagues across the NHS were absent each day last week compared with the previous seven days and almost half of all absences are now down to Covid.

“While we don’t know the full scale of the potential impact this new strain will have, it’s clear it spreads more easily and, as a result, Covid cases in hospitals are the highest they’ve been since February last year – piling even more pressure on hard-working staff.”

It comes as NHS England data show 39,142 NHS staff at hospital trusts in England were absent for Covid reasons on Jan 2, up 59 per cent on the previous week (24,632) and more than three times the number at the start of December (12,508).

The figures suggest one in 25 (four per cent) of NHS staff working in acute hospital trusts are off sick or self-isolating due to Covid.