A letter sent to GPs by the country's medical chiefs has warned of a 'much larger' Omicron wave due to hit in 'two to three weeks', as they told doctors of a huge rollout of the booster programme 'with no notice'.
Greater Manchester's medics have voiced concerns in the wake of Prime Minster Boris Johnson's address this evening, December 12, in which he told all adults that they will be able to come forward to seek a booster jab.
Staff will face a battle to give out the boosters, according to GPs, as they cope with an already unprecedented level of pressure on the NHS at the system's most difficult time of year.
One GP has said his practice will be forced to 'cancel routine work' and 'all staff leave' until the end of December, adding the rollout will 'break general practice'.
In a letter to the Royal College of General Practitioners sent out to doctors, shared with the Manchester Evening News this evening, Professor Martin Marshall, RCGP Chair, and Professor Chris Whitty, Chief Medical Officer for England, warned of the Omicron spread among young adults.
They have written that 'the wave will be much larger in two to three weeks, and if it runs through an upboosted population the subsequent avoidable impact on the NHS, and almost certainly on severe disease and mortality will be significant'.
'The NHS will then be hit with a large wave of patients at the worst time of the year, and at a point it is likely many colleagues will be ill, isolating or caring for family members due to the size of the wave.'

The health bosses have urged for GPs to help with the vaccine effort, amid accounts that some surgeries have pulled out of the programme due to the winter demand already stretching resources.
The leaked letter reads: "Dear Colleagues, we are taking the unusual step of jointly writing to you today to thank you and your practice teams for your immense contribution to the Covid vaccine programme so far – and to appeal for your help yet again in delivering the booster jab to as many people as possible over the next few weeks.
"Even at this very busy point in the year this is now the number one priority for the NHS and we wanted to lay out why GPs are essential to this.
"We fully appreciate that any time vaccinating has a cost to other work, and has to be justified. The speed of onset and spread of the Omicron variant is remarkable. It is now doubling every two to three days, and despite only recently having been established in the UK will shortly be the dominant variant in much of the country, and is likely then to carry on rising.
"It is now clear that people with two current vaccine doses, even if they have reasonable protection against severe disease (we think most will- any vaccination is better than none) have very limited protection against symptomatic disease.
"We are already seeing the first hospitalised cases, with more in A&E and in surgeries. At present it is spreading mainly in young adults, but it will inevitably soon move up the ages and find vulnerable people.
"We have a very narrow window of opportunity to get as much of the population boosted (or vaccinated) as possible. This wave will be much larger in two to three weeks, and if it runs through an upboosted population the subsequent avoidable impact on the NHS, and almost certainly on severe disease and mortality will be significant.
"The NHS will then be hit with a large wave of patients at the worst time of the year, and at a point it is likely many colleagues will be ill, isolating or caring for family members due to the size of the wave. So we must act now and get as many vaccinated and boosted by year end as we can.

"Even with the contribution of our pharmacy colleagues and those working in mass vaccination and hospital-based clinics, without substantial help from GPs the current effort is not going to be sufficient to achieve our target of getting the majority of the population vaccinated in the next weeks.
"There is no doubt that without the efforts of you and your teams, we would never have achieved mass delivery of the first two doses. Now we need the experience and expertise of general practice to intensify the vaccination effort once again if we are to have any hope of replicating, at even greater speed, a similar degree of public protection.
"We understand and appreciate just how hard GPs are working to deliver essential care and services to patients, and we are very grateful to those practices who have already been able to accommodate the additional booster programme. We also realise that general practice is under significant strain, that frontline clinicians are worn-out, and that some of you have had to make tough decisions to step away from the programme to focus on other patient care priorities.
"We don’t underestimate the massive effort required nor the challenge of prioritising clinical care in an environment in which general practice’s contribution during the pandemic has not been appropriately recognised by some people.
"This will however be a time-limited effort- and one which is highly time sensitive. Only GPs can do this. As Chief Medical Officer and Chair of the College we will support you and ensure that your efforts are recognised and valued as they deserve.
"Thank you again for everything you are doing to protect and care for your patients."
But tonight, GPs are crying out for help.
"[It is a] nearly impossible ask. It is going to break general practice," Dr Bhutta, a GP in Hyde, has told the Manchester Evening News this evening.
"It is the busiest time of year for GP surgeries anyway, I'm not sure how we're going to do this. We simply don't have the staff.
"This came out of nowhere. We will have to cancel all leave for staff from now until December 31."

They say they are arranging 'emergency meetings' for tomorrow to figure out how to achieve the huge rollout.
"We will be stepping down routine work for three weeks and just doing vaccination seven days a week," says Dr Bhutta.
"We will continue to carry on with urgent and emergency cases, as well as on-the-day demand.
"We will try our best for our patients."
Another health boss, in charge of the vaccine programme roll out in Bolton, has shared that the NHS body in charge of running the vaccine in Bolton only had 12 hours notice to deliver the extra jabs.

“All Bolton Covid vaccine sites will be working to step up capacity further and see 18+ from tomorrow,” Dr Helen Wall tweeted, “but please bear with us this is a mammoth ask with 12 hours notice.”
"I'm understandably concerned but positive because we have great teams in Bolton and I know we can do this," Dr Wall added, when speaking to the M.E.N.