BOSTON — Some New England hospitals are delaying or rescheduling surgeries because of a shortage of blood donations during the pandemic.

“We haven’t seen anything like this in about 30 or 40 years at least,” Dr. Vishesh Chhibber, director of transfusion medicine at UMass Memorial Health, told the Boston Globe.

Periodic, localized blood shortages are not uncommon, but this shortage is “unprecedented in its scope,” said Dr. Claudia Cohn, chief medical officer for the American Association of Blood Banks.

Officials point toward a number of factors including the typical summer drop in blood donations at a time when surgeries are increasing because of procedures that were postponed during the pandemic.

Nationwide, the Red Cross normally has a five-day supply of all types of blood, said Kelly Isenor, spokesperson for the Red Cross of Massachusetts,

Right now, the supply of the sorely needed type O blood would last only a half-day. “It’s going out faster than it’s coming in,” Isenor said.