LONDON (Reuters) - Britain on Wednesday (today) celebrates 75 years of its National Health Service (NHS), with royals, politicians, staff and patients expressing pride in its past and determination that it will endure in the future despite current challenges.

Launched on July 5, 1948, by a Labour government following the Second World War, its mission was to ensure "everybody, irrespective of means, age, sex or occupation shall have equal opportunity to benefit from the best and most up-to-date medical and allied services available."

One former minister once remarked that the NHS was the closest thing the English have to a religion, such is the widely-held affection for the service and those who work for it.

"For 75 years, the NHS has existed for an enduring moral purpose: To give every single person in our country the security that comes from knowing that if you're sick, you will be cared for," Prime Minister Rishi Sunak said in a speech last week.

But in recent years, the NHS has found itself needing emergency care, struggling to keep up with patient demands, an increasingly elderly and sickly population, and the cost of new medicines and treatments.

The COVID-19 pandemic added another layer of strain onto an already creaking system, and the commemorations come after a winter of crisis followed by strikes over pay by junior doctors, nurses and healthcare workers.

While some workers have now accepted pay offers, senior doctors have also recently voted for walkouts.

A COMFORT BLANKET

Sunak has said that one of his goals is to cut waiting lists, and last week the NHS set out a new long-term workforce plan aimed at securing the service for the future.

On Wednesday, political and health leaders will gather for a service at Westminster Abbey, while King Charles has commemorated the event in Scotland. His son William hosted a tea party for staff and patients.

"Wishing everyone a very happy 75th birthday of the NHS," William said, and his wife Kate added: "thank you so much for all you do."

Among those invited was Aneira Thomas, who was the first baby born on the NHS and was named after its founder, health minister Aneurin Bevan. She was born at a minute past midnight on July 5, 1948.

"It was a turning point in history for the health of Great Britain," she said, adding that the NHS had saved the life of both of her children after brain haemorrhages.

"After the horrors of the war, Great Britain was broken. So to have a National Health Service come into fruition, was like throwing a comfort blanket around the people of Great Britain."