Fullerton, CA - January 20: A nurse fills test tubes with blood to be tested during an American Red Cross bloodmobile in Fullerton, CA on Thursday, January 20, 2022.
CNN  — 

The American Red Cross is sounding the alarm that the United States’ blood supply has fallen by nearly 25% since early August, to what it describes as “critically low levels.”

The organization, which provides about 40% of US blood and blood components, announced on its website Monday that this national blood shortage is potentially threatening the medical care of patients who might have an emergency need for blood or those who depend on lifesaving blood transfusions for conditions such as cancer or sickle cell disease.

As donor turnout fell in August, the Red Cross announced that it saw a shortfall of about 30,000 donations last month alone, amid a busy summer travel season and back-to-school activities.

In its announcement, the Red Cross also pointed to “back-to-back months of worsening climate-driven disasters” as further straining the blood supply since some blood drives had to be canceled due to extreme weather, for instance.

Just a couple of weeks ago, Hurricane Idalia caused more than 700 units of blood and blood platelets to go uncollected in the southeastern US, according to the announcement. Currently, the Red Cross is keeping a close watch on Hurricane Lee and its potential impact on the Northeast region of the country later this week.

“For so many patients living with urgent medical care needs, crises don’t stop with natural disasters,” Dr. Pampee Young, chief medical officer for the American Red Cross, said in Monday’s announcement.

“In fact, in some instances the stress of a disaster can lead to a medical crisis for some individuals battling sickle cell disease. The need for blood is constant,” Young said. “Every two seconds, someone in the U.S. needs blood—an often-invisible emergency that the rest of the world doesn’t see behind closed hospital doors. Now, that urgency has only heightened.”

Overall, the distribution of blood products to hospitals is outpacing the number of blood donations being made, and according to the Red Cross, about 2,500 hospitals and transfusion centers nationwide rely on the nonprofit to collect around 12,500 donations each day to meet patients’ needs.

In early August, the Red Cross announced that more gay men were eligible to give blood, as a more inclusive risk-based individual assessment to determine whether someone is eligible to give blood, regardless of sexual orientation, sex or gender, would be used. Historically, gay and bisexual men were banned from donating.

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Other large blood donation organizations say they are not experiencing a blood supply shortage.

“OneBlood is not experiencing a blood shortage at this time,” spokesperson Susan Forbes told CNN.

Blood Centers of America also says it is meeting local demand. Jenny Ficenec, the organization’s executive vice president, says she is more concerned about sustaining the blood supply, as fewer people donate each year.

“What we’re more focused on is long-term sustainability. The aging donor base is making it harder and harder for blood centers to collect,” Ficenec said.

The majority of people who donate blood to Blood Centers of America are older adults, Ficenec says, adding that in the past 10 years, her organization has seen a 47% decline in donors under the age of 30.

“Less than 20% of blood donations come from 20- to 34-year-olds, and over 45% of blood donations come from donors over 50,” she said of her organization.

Andrea Cefarelli, senior vice president of New York Blood Center Enterprises, agrees that the blood supply is not as healthy as it should be due to a 50% decline in youth donors.

“Schools have not returned to hosting blood drives the way they did pre-pandemic,” she says. “In the New York area alone, we used to work with 500 individual high schools. We’re contacting each and every one of them, begging them to return to having student blood drives.”

Volunteers can make appointments online to give blood or platelets at the website RedCrossBlood.org or by calling 1-800-RED-CROSS.