THE hot cup of tea and biscuits served to blood donors may have stayed the same since 1946. But, the past seven decades have been many 'momentous changes' to the National Blood Transfusion Service, says the NHS.

Alongside Twitter and Facebook pages, there are now apps and web pages making it easy for people to register and make appointments online to give blood. Text messages are even sent to donors telling them when and where their donation has been used.

On cushioned, reclining chairs lined up in church and village halls, hotels, schools and purpose-built donor centres, some 97,297 people gave blood at least once in the North West last year.

However, with half those donors aged 45 and over, the service faces the new challenge of attracting younger volunteers to keep the blood banks topped up.

Just 12 per cent of North West donors are aged 17 to 24 and the NHS is calling on younger people to be "the blood donors of the future".

Mike Stredder, director of blood donation at NHS Blood and Transplant, said: "The birth of the National Blood Transfusion Service in September 1946 was the beginning of a long process of evolution that has seen many, many lives saved or improved thanks to volunteer blood donors."

It was the need to help treat wartime casualties that drove the development of the National Blood Transfusion Service. During the First World War, blood transfusions were adopted to help save those injured on the battlefields, and donated blood was first needed on a large scale during the Second World War.

Blood banks were created to meet the needs of injured civilians and service personnel, and they were taken under the control of the Ministry of Health in September 1946 - with that, the National Blood Transfusion Service was born, now part of NHS Blood and Transplant.

Seventy years ago there were 270,000 blood donors, compared to around 900,000 last year who gave some 1.6 million units of blood. Of last year's donors, around one in six gave blood for the first time.

Modernisation and new technology have played a major role since the early days, when therapy was restricted to the transfusion of whole blood, red cell concentrates and plasma.

In 1946 the only test carried out was for syphilis. Today there is much wider screening of blood and plasma donations for potential infections as new and deadly viruses have emerged, including HIV and the Zika virus.

In 1975 plastic packs replaced glass bottles, allowing a much wider use of blood components and new therapies for patients, including platelets for those suffering from leukaemia.

Every blood donation can save or improve up to three lives, and each day NHS Blood and Transplant needs more than 6,000 donors to give blood at sessions across England to meet patient need. While donors from all blood groups are important there is a particular need for more O negative and A negative donors as both blood groups can be vulnerable to shortfall.

There are four main blood groups – O, A, B and AB - with O being the most common and therefore the most in demand. A regular supply of blood is vital as red cells last 35 days and platelets only a week.

The overall demand for blood is falling by three to four per cent per year, says the NHS, due to improvements in clinical practice.

However, just under 200,000 new blood donors are still needed each year to replace those who no longer donate for reasons such as ill health, pregnancy or foreign travel, and to ensure the right mix of blood groups to match patient needs in the future.

Meanwhile, more Black African, black Caribbean, mixed race and South Asian people are being called on to become blood donors to reflect the ethnic diversity of patients.

Men can give blood every 12 weeks, while female donors must wait 16 weeks between sessions, but platelets can be given every fortnight.

"We want to thank all our loyal donors," said NHS director of blood donation Mike Stredder, director of blood donation. "Your blood is precious and you are doing something amazing, helping to save and improve the lives of others. We hope you inspire the next generation to carry on the great British tradition of altruistic blood donation."

- To register today and book an appointment, visit www.blood.co.uk or phone the 24-hour donor line on 0300-1232323

- Twitter: @givebloodnhs

- Facebook: www.facebook.com/givebloodNHS

- Instagram: @GivebloodNHS

- Youtube: www.youtube.com/user/NHSGiveBlood