The U.S. blood supply used for transfusions is critically low — a situation that's been made worse by the COVID-19 pandemic, according to news reports.
Last week, the American Red Cross, which supplies 40% of the nation's donated blood, reported that it is experiencing a "severe blood shortage," according to a statement from the organization.
The Red Cross typically carries enough donated blood to last for five days if donations were to suddenly halt, according to the Boston Globe. But now, the supply of type O blood — the most in-demand blood type for transfusions since it can be donated to individuals with any blood type — would last only half a day, the Globe reported.
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The shortage extends to blood donation centers across the United States.
"The current situation with the blood supply is the most concerning I have seen in my career," Dr. Claudia Cohn, chief medical officer of the American Association of Blood Banks, told ABC News.
"The majority of blood centers are now reporting a one-day supply or less of blood, far below the levels for which they normally strive," Cohn said.
A number of factors have contributed to the shortage. Blood donations typically drop in the summer months as people go on vacation and schools, which hold blood drives, are closed, the Globe reported. But the pandemic has only added to the problem — fewer people are coming out to blood drives in general, and many blood donation centers are still understaffed, the Globe reported.
What's more, hospitals have seen an increase in patients coming in for surgeries that they had put off during the pandemic, increasing the demand for blood.
"Some hospitals are being forced to slow the pace of elective surgeries until the blood supply stabilizes, delaying crucial patient care," Chris Hrouda, president of Red Cross Biomedical Services, said in the statement.
U.S. hospitals have also seen an increase in trauma cases requiring transfusions. Compared with 2019, the demand for blood at trauma centers has increased 10%, according to the Red Cross.
The shortage could lead to further delays in elective surgeries and cause hospitals to implement even stricter criteria for using blood products in patients, ABC News reported.
"It means blood may not be available for all patients when it is needed, leading to suboptimal care for some patients," Cohn told ABC News.
Originally published on Live Science.