Now, as the prime minister prepares to unveil his roadmap out of lockdown, NHS Providers, which represents hospital trusts in England, has given Mr Johnson the criteria that health leaders believe must be met before any restrictions can be relaxed.
Lockdown restrictions should not be lifted until it is clear that the NHS will be able to cope with a rise in Covid cases, hospital leaders have warned Boris Johnson.
They include making sure that cases are at a level where the NHS can treat all the patients it needs to, and having a “robust, effective” strategy to identify and control outbreaks of Covid variants.
Chris Hopson, the chief executive of NHS Providers, said: “We have had the debate about when and how quickly to lift restrictions several times before. Each time those arguing for a rapid relaxation were wrong and we had to reimpose restrictions, losing unnecessary lives and causing unnecessary long-term patient harm in the process.
“If this is to be the last national lockdown, we have to learn the lessons from last year and take a cautious approach.”
Mr Johnson has said he hopes lockdown can be eased in the coming weeks, with emerging research on the success of the vaccine rollout giving “grounds for confidence”.
The minister for Covid vaccine deployment, Nadhim Zahawi, told BBC Radio 4’s Today programme that full data from two big research projects being carried out by Oxford University may not be available for several weeks.
He said: “We’re beginning to see more and more data, but at the moment it’s far too early to begin to speculate.”
The government is planning to publish a roadmap on Monday next week that will outline the easing of lockdown, with schools likely to reopen first.
During the second wave, hospitals saw more than double the number of coronavirus patients in hospital after the emergence of the new, more easily transmissible variant that was first detected in southeast England.
Hospitals and intensive care units were overrun, with almost 40,000 Covid-19 patients being treated at the peak, while nurses were forced to work at unsafe staffing levels and patients were airlifted across the country to free up beds in the hardest-hit areas.
NHS Providers has set four tests they say must be passed if the health service is to avoid being further overwhelmed.
They said the infection numbers and R-rate for the virus must drop significantly to prevent a resurgence and that the NHS needs to have capacity return to levels where it can treat all the patients it needs to. Tens of thousands of operations, including for cancer, have been delayed because of the pressure on hospital beds.
In the letter to Mr Johnson, NHS Providers added that the vaccination campaign must reach a stage where there is adequate protection to avoid unnecessary deaths, and last, it says there must be a strategy in place to quickly spot and control outbreaks caused by new variants.
Mr Hopson warned that with only the top four priority groups vaccinated so far, there was still plenty of scope for significant numbers of deaths, while more work was needed to ensure the test and trace service was up to the job of controlling new variants of the disease.
He said: “The evidence on Covid-19 cases, NHS capacity, progress with vaccinations and readiness to combat Covid-19 variants all show that it is much too early to start lifting restrictions. Case numbers are still far too high.”
He added: “The NHS is still at full stretch and trust leaders believe this will continue for at least another six to eight weeks.”