Canceled appointments at Midpeninsula blood banks are causing a critical shortage, said local blood center officials. They are calling on people to come out to drives now through the end of this month as donations of all types of blood and of plasma are needed throughout the Bay Area.

The shortage is in part driven by a cessation of corporate blood drives as employees work from home and residents sheltering in place to slow the spread of COVID-19.

Potential donors are exempt from the shelter-in-place order, which does not cover essential health services, Stanford Blood Center said in a statement on Wednesday. Stanford Blood Center is hosting mobile blood drives on March 19 and April 3 on the Stanford campus and on March 30 at Stanford Health Care’s main hospital. American Red Cross California Blood Services is holding a blood drive through March 31.

"While it may seem as if the world has stopped — and indeed, in certain sectors, it has — we as a community cannot forget about hospital patients in critical need. Even with a shelter in place in effect, individuals in our community — potentially even individuals we know personally — will continue to be in car accidents, need emergency organ transplants, give birth to babies in critical condition, and need chemotherapy. In short, there will still be lives that need saving," Harpreet Sandhu, CEO of Stanford Blood Center, said in a statement posted on the center's website.

Blood centers around the country are warning of devastating shortages in all blood types if the lull in donations persists. On March 12, officials from the Food and Drug Administration and the Department of Health and Human Services urged Americans to turn out in force, Stanford Blood Bank noted.

"If we don't have people coming in to donate now, we are going to have a larger problem," said Jenn Wagner, communications manager for Stanford Blood Center. "We want people to know that it is very safe to donate blood. Every potential donor is given a mini-physical exam when they first arrive, and we take a medical history. We have also made social distancing part of our practice wherever possible and take every preventive measure to keep our donors safe."

People who are healthy, feeling well and meet other requirements for donation are likely eligible to donate blood, Wagner said. Also, those who haven’t traveled to a high-risk country or been in direct contact with a confirmed COVID-19 case can be candidates for donation, she said.

"People older than 65, or those with health conditions that put them at a heightened risk of infection, should be cautious and well-informed of current recommendations from public health and government agencies, but are able to donate if they meet all standard criteria for donation," she said.

American Red Cross California Blood Services has also put out an urgent call for blood donations. The cold and flu season has already impacted the nation's ability to maintain its blood supply, the Red Cross said in a statement. As the number of coronavirus cases grows in the U.S., the number of people eligible to give blood for patients in need could further decrease.

"There is no data or evidence that this coronavirus can be transmissible by blood transfusion, and there have been no reported cases worldwide of transmissions for any respiratory virus, including this coronavirus, from a transfusion," the organization said.

"The Red Cross only collects blood from individuals who are healthy and feeling well at the time of donation and who meet other eligibility requirements. At each blood drive and donation center, Red Cross employees follow thorough safety protocols including wearing gloves, routinely wiping down donor-touched areas, using sterile collection sets for every donation, and preparing the arm for donation with an aseptic scrub. These mitigation measures will help ensure blood recipient safety, as well as staff and donor safety in reducing contact with those who may potentially have this respiratory infection."

The Red Cross has implemented new blood donation criteria out of an abundance of caution. People are asked to postpone their donation for 28 days following travel to China, Hong Kong and Macau, Iran, Italy and South Korea; if they have been diagnosed with COVID-19; or had contact with a person who has or is suspected to have the virus.

Vitalant, formerly Blood Centers of the Pacific, is also calling for badly needed donations. The blood bank needs all types of blood, but particularly type O, both positive and negative, and platelets. The platelets have only a five-day shelf life. Type O is the universal donor blood type and is used for all types of trauma, so there is a great need, they said.

Potential donors can make an appointment to donate blood at the following locations:

• Stanford Blood Center: 888-723-7831; stanfordbloodcenter.org.

• Red Cross: RedCrossBlood.org.

• Vitalant: 877-258-4825; vitalant.org.

Find comprehensive coverage on the Midpeninsula's response to the new coronavirus by Palo Alto Online, the Mountain View Voice and Almanac here.