WASHINGTON (CBS Local) — The American Red Cross, facing a critical shortage of Type O blood, is offering a $5 Amazon gift card via email to donors as an incentive to boost supply.

The ARC said it currently has less than a two-day supply of type O blood for emergency rooms.

“Type O-negative is the universal blood type and is what emergency room personnel reach for in the most serious situations when there is not time to determine a patient’s blood type,” said Dr. Pampee Young, chief medical officer of Red Cross Biomedical Services. “Type O-positive blood can be transfused to any positive blood type patient and is also critical in trauma situations. We are asking donors to give blood as soon as possible to ensure patient needs can be met in the days and weeks ahead.”

The Red Cross likes to have a five-day supply of Type O on hand, but it’s tough to do that, especially at this time of year.

“In April, we collected a lot less blood than normal. Most of that was due to spring breaks ironically enough. Twenty percent of our blood collection during the school year comes from school drives, colleges and high schools,” Dan Tobin, director of marketing & communications for the Greater Pittsburgh area’s Red Cross, told CBS Pittsburgh.

The Red Cross says patients could end up noticing a shortage down the road if things don’t change soon.

“If blood supply runs too low, you could see somewhere down the line, things that are elective in nature maybe needing to be held off just because you want to reserve the blood for emergencies,” said Tobin.

The offer is good through June 10.

For information on how to donate, make an appointment using the Blood Donor App, at RedCrossBlood.org or by calling 1-800-RED CROSS (1-800-733-2767).

A blood donation can take about an hour, but the actual donation itself only takes about 10 minutes.

Donors can also save up to 15 minutes at the blood drive by completing a RapidPass, which allows donors to complete the pre-donation reading and health history questionnaire online, on the day of donation, from a mobile device or computer.