The American Red Cross has announced a critical shortage of type O blood and is urging eligible donors to give now to help patients facing trauma and other life-threatening situations.

As a thank-you for helping replenish the blood supply, all donors who come to give blood or platelets through June 10 will receive a $5 Amazon.com Gift Card via email.

Right now the Red Cross is reporting less than a two-day supply of type O blood available for emergency rooms, where it can be most critical. That means six units of type O blood are available for every 100,000 people – but at least 14 are needed every day.

While 7 percent of the U.S. population has type O negative blood, it can be transfused to patients with any blood type, and it’s what hospital staff members reach for during emergencies when there isn’t time to determine a patient’s blood type.

Type O positive blood is the most transfused blood type and is also critical in trauma situations.

“All blood types are urgently needed, but we’re facing a critical shortage of type O blood – the blood group most needed by hospitals,” said Cliff Numark, senior vice president of Red Cross Blood Services. “Because it’s vitally important for hospitals to have type O blood available when every second counts, type O donors are urged to donate now and make a point to donate often.”

The Red Cross collected approximately 11,500 fewer type O blood donations than needed to sustain a sufficient blood supply.

Donors of all blood types, especially type O, are urged to urged to make an appointment to donate using the Blood Donor App, at RedCrossBlood.org or by calling 1-800-RED CROSS. Eligible donors with type O blood are encouraged to make a whole blood or Power Red donation, where available. During a Power Red donation, donors give a concentrated dose of red blood cells during a single donation, allowing them to maximize their impact.