The American Red Cross says it currently has a significant need for type O negative blood, which can be transfused to patients with any blood type and is often used in emergencies.
The Red Cross says eligible donors with type O negative blood are encouraged to make a whole blood or double red cell donation where they can. During a double red cell donation, the Red Cross explains, two units of red blood cells are collected while most of the plasma and platelets are returned to the donor.
Hospitals depend on O negative donations, but less than 7 percent of the U.S. population has that blood type.
To make a blood donation appointment or find out about blood drives in your area, you can visit redcrossblood.org or call 1-800-733-2767.