Health officials have launched an urgent plea for more black people to give blood.
NHS Blood and Transplant (NHSBT) said that 40,000 more donors were needed to meet growing demand for Ro blood, a subtype that is more common among black people.
The authority said that there was a 75% increase in the amount of Ro blood issued to hospitals in England between 2014 and 2016.
Much of the blood is used to treat sickle cell disease, a condition particularly common in people of African or Caribbean descent.
People with sickle cell disease have abnormal red blood cells that do not move around vessels easily and have a reduced capacity for carrying oxygen around the body.
The condition, which affects around 15,000 people in the UK, can be extremely painful and cause life-threatening infections and other complications such as stroke and loss of vision. Blood transfusions can help prevent or relieve these symptoms.
To get the best treatment, patients need blood that is closely matched, which is most likely to come from someone of the same ethnicity, but NHSBT said that only 1% of people who give blood in England are black.
To mark National Blood Week, the authority has launched a new campaign – #ImThere – to try to encourage more people to register and donate.
Mike Stredder, NHSBT’s director for blood donation, said: “We need to ensure that we have the right mix of donors and blood types to help meet the needs of all patients who need life-saving treatment, especially those with conditions like sickle cell disease who require blood which is more closely matched than by group alone.
“In recent weeks, we have been overwhelmed by the numbers of people stepping forward and wanting to donate and show their support for those affected by recent tragic events.
“Thankfully, due to the loyalty of our regular donors, our emergency stocks have proven to be strong and sufficient, but we still need to ensure that we can be there every day, for every patient who needs us.”
The mother of a 10-year-old sickle cell disease patient has backed the campaign. Matthew Akinmuleya, from London, was diagnosed with the condition at birth and has since required a blood transfusion every month.
His mother, Omotolani Olabifi, said: “The hospital tried to see if he could manage without blood transfusions, but he had so much pain, A&E admissions, IV and oral morphine. Nothing could help.
“The blood he receives makes a huge difference. In the first two weeks after his transfusion he is like a normal 10-year-old. He has energy and is able to go to school.
“But after three weeks, he starts to look pale, jaundiced, tired and pain takes over. In the week before his transfusion, he will be in severe pain and often admitted to hospital.
“As a mother and carer, I really appreciate all of those who donate. My child would not have survived without you. We need the help for our children to help them live. Without this blood, his story would be so different.”
To find out more visit www.blood.co.uk, call 0300 123 23 23 or search for the NHS Give Blood app