Attendances to Scotland's accident-and-emergency units in the week before Christmas have risen by almost 20 per cent on the previous year after a massive increase in flu cases.

A total of 26,569 people visited A&E during the week, up almost 20 per cent from the 22,267 attendances in the same week in 2016.

It comes after A&E waiting times remained below a key target set by the Scottish Government and NHS boards.

The Royal Hospital for Children in Glasgow experienced a 44 per cent increase in attendances while the city's Queen Elizabeth University Hospital saw a 26 per cent rise.

Wishaw, Raigmore, Borders and Inverclyde hospitals also saw increases of more than 25 per cent.

Health boards attributed the rise in demand to acute seasonal illnesses, with the rate of GP consultations for flu and respiratory infections rising by over a quarter during the period.

NHS24 and the Scottish Ambulance Service also reported rises in call volume, with NHS 24 reporting more than 90,000 calls during the eight-day festive period shutdown.

Concerns over the influx of patients led to a number of health boards -- including NHS Lanarkshire, NHS Grampian, NHS Tayside, and NHS Forth Valley -- to only visit A&E if it was absolutely necessary.

Statistics also show that A&E waiting times remained below a key target of 95 per cent of patients being either admitted, transferred or discharged within four hours.

The figures for the week ending December 24 also showed only 83.3 per cent of patients met the four-hour target.

It represents a slight increase from 81.1 per cent the previous week and is down from 93.5 per cent on the same week the previous year.

Separate monthly statistics show that during November, 93.3 per cent of people were seen within the same target.

The figure is down slightly from 94.4 per cent in October and 93.6 per cent in November 2016.

Health Secretary Shona Robison said: "Our NHS and community health service do a fantastic job all year round but there is no doubt that winter can bring additional demands, and I'd like to thank them once again for the dedication they have shown during this busy winter period.

"We're working with boards to help them cope with pressures and this year alone we have invested £22.4 million to create extra resilience across the system."

Deputy Chief Medical Officer Dr Gregor Smith said: "These figures illustrate the demands being placed on health staff right across Scotland as a result of spikes in various illnesses such as flu.

"We can all play a part in ensuring demand on our most acute services is minimised, however, by taking time to think of the best way to access treatment.

"Only go to A&E if you have had an accident or you are experiencing significant difficulties, such as trouble breathing or severe bleeding."

Meanwhile, more than 20 planned operations were cancelled per days in Scotland hospitals in November for reasons including lack of beds, staff sickness and dirty equipment.

A total of 664 operations were called off by hospital staff due to capacity or other non-clinical reasons that month, the latest official figures show.

Causes for these cancellations included beds, staff or equipment being unavailable, workers being ill or unavailable due to an emergency operation taking priority and equipment being dirty.

Further reasons included operating theatre sessions over-running, leading to the patient cancelling.

There were 30,820 planned operations across Scotland in November and 2,720 (8.8 per cent) of these were cancelled, down from 9 per cent the previous November but up from 8.5 per cent on October 2017.

Health Secretary Shona Robison said: "Decisions to cancel planned operations are never taken lightly and we are working with health boards to make sure they manage capacity and planning in order to keep all cancellations to a minimum."