A blood supply shortage in the US has reached a “crisis” level, according to the American Red Cross, which says it is the second time in its 150-year history that levels have been this low.
Factors including wildfires and extreme heat have combined to create the current situation, Dr Courtney Lawrence, who works with the American Red Cross, told the BBC.
Supply levels dropped by a quarter just last month. The crisis has struck during summer, when the amount of blood needed by hospitals typically increases.
That is because of an increased number of car accidents and more people spending time outdoors, resulting in more injuries that require blood transfusions, Lawrence said.
Most donor blood is O+
O- is great because it is (almost always*) usable by anyone of any blood type, but only like 7% of people have it, so the overall supply is not very high and it’s typically reserved for emergencies and O- patients.
O+ can be given to most people because most people have O+ blood. Something like 30-40% of people have O+ and can thus receive O+ donations. All the Rh+ blood types can receive O+ blood too, which accounts for the vast majority of people. A+ is something like 25-30% of the population and B+ is like 10%. Altogether, O+, A+, B+, and AB+ make up probably about 75-85% of the population, and all of those people can receive O+ blood donations, thus the supply of O+ blood is the most-needed most of the time.
Obviously they also want as much O- as possible too. Hell, they want all of them all the time except AB type blood from females.
*Blood typing is actually a lot more complicated than A/B antigen and Rh factor, so some people with certain antigens need very specific donor blood or autologous blood that they donate themselves prior to a procedure or whatnot.
Great reply Thanks
What is different about AB type from females? That describes me and I’ve almost earned my 2 gallon pin, the ladies in the blood mobile are always happy to see me.
I googled it and this is from blood.co.uk: