The US FDA has called on healthy Americans to donate blood as supplies around the country dwindle.

“The number of blood donations has been dramatically reduced due to the implementation of social distancing and the cancellation of blood drives,” the FDA said in a statement, calling the maintaining of adequate levels of America’s blood supply “critical.”

“Every two seconds, a patient needs a blood transfusion,” the FDA said in a statement. “In order to ensure that blood is available to those who need it most, it is important for healthy individuals who are able to donate to take the time to do so.”

US Surgeon General Jerome Adams took to Twitter to call Americans to donate, telling them “part of preparedness is a robust blood supply.”

For those fearing infection, the FDA assured Americans that blood donation centers are safe.

“Blood donation centers can facilitate the safe donation of blood because they are skilled in infection control practices and already have procedures in place to prevent the spread of infections. Blood donation centers always take steps to prevent staff and donors who are not feeling well or who have a fever from reaching the donor area, and they are now taking additional social distancing precautions wherever possible, consistent with the President’s Coronavirus Guidelines for America.”

The FDA added that many blood donation centers can arrange appointments to minimize the time it takes to donate blood and that centers can arrange to call a donor’s mobile phone when they’re ready for the donor to come in.

Those interested in donating blood may contact the following organizations to find a local blood collection site and to schedule an appointment: