The national blood shortage that prompted U.S. Department of Health and Human Services Secretary Tommy Thompson to issue a plea to the public Monday continues to affect central Pennsylvania.

While low levels of negative blood types have been a problem for over a month, in recent weeks, the shortage has affected area hospitals.

For the past few weeks, hospital orders for A-negative and B-negative blood types have been cut by 30 percent, and O-negative blood was being sent to hospitals on a need-only basis, said Jennifer Mansfield, a representative from the regional American Red Cross.

Yesterday, due to improved levels of the O-negative supply, the Red Cross began to fill hospital orders for the blood type as usual, Mansfield said. However, the orders have been so large that the blood bank will likely have to return to need-only distribution, she added.

No area hospitals have had to cancel any surgeries, but cancellation of elective surgeries are a possibility if blood supply levels do not improve within the coming weeks, Mansfield said.

In Monday's statement, Thompson also emphasized the importance of replenishing the national blood supply, calling the need for improvement of the shortage an "urgent national priority."

Because donating blood is "easy and safe," Thompson also asked anyone who is able to donate blood as soon as possible.

"While 60 percent of Americans are eligible to donate blood, only 5 percent do," Thompson said. "We can do better. We must do better."

While blood supply levels usually decrease during winter months, this year the drop in the blood supply was worsened by the severe winter weather in Centre County, Mansfield said. The Red Cross had to cancel several blood drives, causing the blood bank to lose a potential 1,000 donors, she said.

Wendi Keeler, a Penn State Red Cross field representative, said winter is a difficult time to donate blood. During winter months, many people are sick, and those with any cold or flu symptoms are ineligible to donate, she said.

However, with the Interfraternity Council/Panhellenic Dance Marathon (Thon) approaching, the Penn State community has many opportunities to donate blood, Keeler said.

The Red Cross will be donating $2 to Thon each time someone gives blood on campus during organized blood drives, Keeler said. Starting this semester, student organizations will sponsor on-campus blood drives nearly every day until Thon, she added.