Blood is not like drinking water - you can't stockpile large supplies for use in emergencies. It has to be fairly fresh. And so the American Red Cross finds itself in its usual summertime bind of critically needing donations.
Red Cross Communications Manager Angie Bermudez says it's tough when 20 percent of blood drives take place on college campuses and at high schools.
She says with summer vacations, this is the time of greatest need.
"We're missing a large percentage of our regular donations," Bermudez says.
Bermudez says over the last 11 weeks, donations are down about eight percent. That represents a whopping 80,000 fewer donations.
All blood types are needed, but O-Negative blood can be used by anyone in need.
Platelet donations are also needed. Platelets are a clotting component of blood that help patients with burns or cancer, or bone marrow recipients. Platelets have to be used within five days of donation, so a fresh supply is critical.
Find a donation center or blood drive near you: