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For example, if your blood type is A positive, it will have both A and RH antigens present. ... Unfortunately, however, an O negative recipient can only receive blood from a donor who is also O negative. So, now you know why demand for O negative blood donations is so high.
GIVERS NOT TAKERS
Those with O- can only receive from other O- donors.
O positive red blood cells are not universally compatible to all types, but they are compatible to any red blood cells that are positive (A+, B+, O+, AB+). ... Type O positive blood is critical in trauma care. Those with O positive blood can only receive transfusions from O positive or O negative blood types.
