Should the government do more to protect the NHS?

Doctors and health service leaders are warning the NHS is on the edge of a crisis, staff are burnt-out and Covid cases are rising sharply - but, in England, the government says there is no reason to change tack.

So far, ministers have refused to budge from their Plan A to deal with Covid this winter - which is to offer booster jabs and get more young people, including 12-15 year olds, vaccinated.

But there is growing pressure to move to its stricter Plan B - which would put England on a similar path to Scotland and Wales, where face coverings are still compulsory on public transport and in shops. People could also be advised to work from home and Covid passports introduced for entry to large events.

These are seen by some as relatively small changes to most people's lives and a very long way from the strict restrictions of earlier in the pandemic. And for some on the frontline, taking those actions now could make a huge difference in the long run.

• What is Plan A and Plan B for Covid this winter?

• Is the pace of the Covid booster rollout too slow?

• Why are UK Covid cases so high?

Prof Charlotte Summers, who works in intensive care, told the BBC that the situation was "incredibly serious", with one in five ICU beds in UK hospitals occupied by someone with Covid-19.

She said doctors were treating more patients ill with Covid, who tended to stay longer in ICU, as well as more people with non-Covid emergencies, and this was reducing their ability to catch up on the massive backlog of elective surgery.

Controlling the numbers of Covid patients in intensive care would make a "significant difference", she said, adding that there was also the workforce to consider.

"Staff have left intensive care units so we have fewer than we had at the start of the pandemic," Prof Summers said. "So, providing services with exhausted staff, fewer staff and more patients is incredibly challenging."

According to the Intensive Care Society, there are 823 patients with Covid in beds which can provide mechanical ventilation, out of a total of roughly 4,000 adult intensive care beds across the UK. That's way down on the winter peak, when extra wards and hospitals were built to care for the most seriously ill.

The majority in intensive care are not vaccinated, Prof Summers said - although precise figures on vaccination status have not been published.

So why is the government not budging?

The vaccination programme is working and has weakened the link between the numbers of people infected with the virus and the numbers ending up seriously ill in hospital and dying.

Even as UK cases rise above 45,000 a day, hospital admissions and deaths have stayed relatively flat over the last few months - and it's not clear yet whether slight rises in the last few days are part of a long-term trend.

Prof Paul Hunter, from the University of East Anglia, said what happens next was "difficult to predict" and cases could peak this month and start to fall again.

It's acknowledged that the NHS in England is clearly extremely busy, but the 6,000 Covid patients in hospital in England equates to 7% of all hospital beds. And there were more Covid patients in hospitals at the start of September 2021.

So the focus is to get more people vaccinated quickly - by speeding up access to booster vaccines for the over-50s, and jabs for young teens in vaccination centres and schools, as well as targeting the five million people who've so far refused a vaccine.

More than four million people out of 30 million who are eligible have now had a booster jab in England, but across the UK as a whole, 14% of people aged over 12 are still unvaccinated.

The drive to get more people vaccinated is backed up by official government figures, which show that in every age group, the rate of hospital admissions is much higher among unvaccinated people than those who are fully vaccinated.

It's a plan that is also backed by a number of senior scientists.

Prof Andrew Pollard, head of Oxford University's vaccine group, who helped develop their Covid vaccine, said the real issue was protecting people who had not had any vaccine doses and those with weakened immune systems, who were ending up in intensive care.

On the whole, he said people with Covid in hospital were staying for a shorter period of time than before, and were more likely to be frail and elderly.

Because the virus was spreading in the community among vaccinated people, there would be "an inevitable feed-through" into hospitals where people could be admitted for other reasons but then test positive, he added.

"Both vaccines are holding up well against severe disease," Prof Pollard said, adding that transmission among young adults "will extend immunity even further".

When will Plan B be triggered?

There's no magic number or set of figures that would mean moving from the current Plan A.

This week Health Secretary Sajid Javid said the vaccination programme remains its first line of defence, and there were no current plans to bring in Plan B "at this point".

But the government also says it will keep a close watch on the number of Covid patients in hospital, any sudden changes in trends and the overall state of the NHS.

As the British Medical Association and NHS leaders have their say on the matter, the pressure to change course is ramping up.

"Being pre-emptive now would mean there is less likelihood of ending up in a further lockdown," said Dr Nathalie MacDermott, from King's College London, who described Plan B as only three simple steps to protect others.

However, it's not known how effective compulsory mask-wearing would be in reducing cases.

Restrictions in the rest of the UK already reflect many of these Plan B measures, but cases in Scotland and Wales are still edging up.

Deciding what steps to take as winter approaches will involve considerations over the economy, over jobs and over schools - not just public health.