The NHS is probably the UK's most fiercely loved institution.

It excites more public affection than the monarchy, more loyalty than the BBC and more pride than the pound. The egalitarian principle it embodies of delivering the same level of health care, free at the point of delivery, for everyone from millionaires to single parents on benefits, makes most British citizens proud.

It commands this unique status in spite of its widely acknowledged flaws; no one expects the NHS to be perfect.

But there is a difference between the acceptable shortcomings of an institution that is basically functioning well and the first signs of a serious impending crisis. Difficulties currently facing the Scottish NHS unfortunately fall into the latter category. The health service is now undergoing what is arguably its greatest challenge in more than a generation, namely coping with a population that is both growing and ageing, all at a time of public funding constraint.

In Scotland, the cracks have been showing for some time, and this week there has been more worrying news. In the decade to 2013/14, official figures show that the number of people treated in hospital increased by 23 per cent, while over the same period the number of available hospital beds fell by seven per cent. The NHS has managed to pull off this remarkable feat by reducing where possible the length of time that patients remain in hospital but, with people presenting themselves to medical staff with increasingly complex medical needs, there is only so far that tactic can be pushed.

At the same time, cancer waiting times are being missed, partly due to the fact there are more, older patients presenting with the disease.

These pressures are being felt all over the UK. So it is no wonder that the future of the NHS formed a central plank of the recent referendum campaign and is now prominent in the pre-election phoney war being played out between the main UK parties. The question facing governments both north and south of the Border is: how can the NHS be properly resourced to meet the challenges ahead?

One plank of the Scottish Government's strategy for easing pressure on hospitals is to integrate health and social care services so that more older people can be cared for in the community for longer, but progress has been rather slow. Figures released a month ago show that bed-blocking, where patients continue occupying beds when they are medically ready for discharge, is at its highest rate in four years, with the number of patients waiting more than six weeks to be discharged having tripled in a year. In most cases, patients were stuck waiting for arrangements to be made for their ongoing care in the community.

As part of our NHS: Time for Action campaign, The Herald is calling for a review of health and social care services, to ensure the right staff and resources are in place to cope with the ageing population. We have also called repeatedly for an honest debate about how to fund the NHS. What is clear is that the status quo is untenable.