Since Hurricane Irene forced blood drives to close over the weekend, the New York Blood Center (NYBC) is in urgent need of blood donors. An estimated 2,000 donations were lost, leaving the normal three-to-five day inventory level to below the two-day minimum.

Several blood types are needed, including O-negative, which can be transfused into anyone, according to a press release.

"We anticipated the potential effects of Irene, and delivered extra blood in advance to our 200 partner hospitals," said NYBC Vice President Rob Purvis. "Our first priority remains getting them whatever they need for the care of trauma and cancer patients."

Due to concerns for the safety of its donors and staff, NYBC closed its donor centers and cancelled all blood drives on Sunday, August 28. "With Labor Day right around the corner, we're between a rock and a hard place," Purvis added. "We need the help of our communities to replenish the blood supply."

The shelf life of platelets is only five days, and the shelf life of red blood cells is 42 days. About one in seven people entering a hospital needs blood.

The center serves more than 20 million people in New York City, Long Island, the Hudson Valley and New Jersey.

Donors can call 1-800-933-2566 or visit the center's website at www.nybloodcenter.org for more information.

The Associated Press contributed to this report.