The NHS is in a vicious cycle - and it is difficult to see what will break it, says health correspondent Geraldine Scott.

A winter crisis, a recruitment crisis, a funding crisis - take your pick as to which crises our health service is in this week.

It has been a dismal few weeks for those working in the NHS, with patients treated in corridors, hospitals full and ambulances stacked up outside emergency departments.

It has also been chaos for patients, who have waited hours upon hours to be seen.

Every winter the service comes under pressure, and hospitals, GPs, paramedics prepare well for this. But those on the frontline have told me that this year felt worse, more pressurised, less safe, than others.

So what was different?

If we look long-term, funding is a key issue here, and one which has been a hot topic this week with Labour leader Jeremy Corbyn asking Theresa May whether she will increase the cash the health service gets. Mrs May's own also made the call, with Boris Johnson asking for an extra £100m a week for the service.

Budgets have tightened over the last few years. Yes, health spending has increased by around 1.2pc above inflation since 2010/11, and this is set to continue throughout this parliament.

But before than - up until 2010 - the NHS enjoyed an annual inflation-proof growth rate of almost 5pc stretching right back to the 1950s.

The problems caused by this are laid bare in the multi-billion pound deficits seen across NHS trusts.

It is true that the NHS was handed extra funds by the Chancellor in November, but experts do not think this is enough. The Nuffield Trust thinktank said the amount 'was not set to keep pace with what patients need'.

Recruitment is also problematic. In the east of England it was revealed this week that just one in 10 nursing vacancies were filled during a period of last year.

And the week before we revealed how more nurses were leaving the profession than were joining.

The UK has fewer doctors and nurses than many other comparable countries both in Europe and across the world.

So workloads for those who remain are heavier, they work longer hours, and those hours they do work are more stressful than before - no wonder they're not sticking around.

Patients are also stuck in hospital due to delayed transfers of care, known as bed blocking. This is when they are medically fit to leave but cannot because, more often than not, the social care is not in place for them.

Staff are also leaving due to Brexit. It is something many Brexiteers dispute, but those on the ground say it is so and hospital bosses have sought assurances from the government that their staff will be safe.

The NHS is hugely reliant on EU staff - there are 54,000 in England alone - to lose even a proportion of them would be a massive blow.

In the shorter terms, hospitals have fewer beds than last year, so are hit hard by a the surge of illness.

And NHS England said the service 'has been under sustained pressure [because of] high levels of respiratory illness, bed occupancy levels giving limited capacity to deal with demand surges, early indications of increasing flu prevalence and some reports suggesting a rise in the severity of illness among patients arriving at A&Es'.

Overall, the story of the NHS is one of success. It is still one of the best healthcare systems in the world, but Mrs May's apologies to patients are not enough.

The anger from the public is purely directed at her as whenever we write a story on when things do not go wrong there is an outpouring of support for staff who work so hard.

To be clear, staff on the frontline do a heroic job.

But they are struggling, and while more money might not be a panacea - there are a number of other things to address - it would not hurt and may ease the pressure.