The NHS has issued a blood shortage alert, saying it has less than two days’ worth of some blood types.
The public has been urged to donate and hospitals have been told to restrict the use of O type blood. O negative donors are often called “universal donors” because they can donate red blood cells to anyone of any blood type.
Just 8 per cent of Britons have O negative blood but it makes up for around 16 per cent of hospital orders.
NHS Blood and Transplant (NHSBT) said it only has 1.6 days’ worth of O negative blood and overall national supplies across all blood types is 4.3 days.
It said stocks of blood have dropped to “unprecedentedly low levels” because of a “perfect storm of increased demand of O type blood from hospitals following the recent cyber attack which has impacted London hospitals” and reduced collections due to high levels of unfilled appointments at donor centres in city and town centres.
NHS England was hit by a ransomware attack in early June, which led to surgeries and tests being cancelled and the disruption of patient care.
Blood testing services at some hospitals were compromised after the Russian Qilin gang targeted the pathology firm Synnovis, which meant they were unable to match patients’ blood at the same frequency as usual.
Members of the public with O negative and O positive blood types were urged to book appointments at donor centres.
NHSBT has written to hospitals to issue an “amber alert” and use substitutions for O type blood where safe to do so.
Donations typically drop during the summer as people go on holiday, while changeable weather and hot days can mean some people are unable to donate because of a lack of hydration or lower iron levels in their blood, the NHS said.
Hospitals will continue to carry out urgent, emergency or trauma surgery, cancer surgery, transplant surgery and blood transfusions to treat people with long-term conditions.
Wait times to book an appointment on the NHS website were around 40 minutes at 2.30pm on Thursday as donors came forward to donate.
Dr Jo Farrar, chief executive of NHSBT, said: “We urgently need more O group donors to come forward and help boost stocks to treat patients needing treatment.
“Last month we saw an incredible response from donors who answered our call and filled up our centres, helping us meet the increased demands for blood throughout June. However, seven weeks on, the need for O negative blood in particular remains critical.”
She said they were making an additional 1,000 appointments per week available, which can be booked online.
Dr Gail Miflin, chief medical officer at NHSBT, said blood donations are needed every minute for emergencies, childbirth and routine treatments.
Professor Sir Stephen Powis, national medical director for NHS England, said: “We’re seeing an increased demand for blood and shortages of stock so it’s important that donors come forward for appointments.
“With thanks to regular blood donors across the country, hospitals will continue to access stock when necessary and prioritise it for those who need it most.”
An appointment to donate can be booked on the NHS website, on the GiveBloodNHS app or by calling 0300 123 23 23.