This year's brutal winter has left York and surrounding areas with a blood shortage.

More than 40 blood drives in the region were canceled in January, leaving the Greater Chesapeake and Potomac Blood Services Region of the American Red Cross short of about 1,100 blood donations, said communications manager Steve Mavica. The chapter, which serves York and Adams counties, Maryland, Washington, D.C., and Northern Virginia, collects about 1,000 units of blood a day, he said.

"(January's cancellations) would be like the Greater Chesapeake and Potomac closing its doors for over a day," Mavica said.

Across the country, January's severe weather forced the cancellation of about 770 Red Cross blood drives and more than 25,000 uncollected blood and platelet donations, according to a news release.

With more wintry weather on the way, all blood types are needed to help build up the depleted blood supply, the release said.

Restocking: Since there's no substitute for human blood, the only way to do that is for more people to step up and give, Mavica said.

"The only source that we have is from a blood donor, for them to roll up their sleeves and give generously," he said.

With a shelf life of only 42 days — and five days for cancer-patient-saving platelets — blood is a perishable product, Mavica said.

"The need for blood is constant," he said.

There is an especially urgent need for blood types O positive, O negative, A negative and B negative, Mavica said. The O negative blood type can be transfused into any patient, and A and B negative are in demand because they are rare, he said.

"If there's not blood on the shelf when needed, victims and cancer patients go without," Mavica said.

Thankfully, the Red Cross has a national inventory — which is lower than usual but not in a shortage — and the capability of moving blood to hospitals in need, he said.

Winter woes: The winter makes for a challenge when trying to keep blood inventory stocked, Mavica said.

"It's been a little bit worse this year," he said. "We've had a bit higher number of storms this year than we did last."

And it's not only about the winter weather: When flu season peaks in January and February, many people aren't well enough to donate, he said. "It's just a confluence of challenges when we get into the winter months," he said.

But Mavica said there's usually an uptick in donations starting mid-February into March.

"We hope folks actually come out and help us return that supply back to a healthy level," he said.

— Reach Mollie Durkin at mdurkin@yorkdispatch.com.