The American Red Cross is experiencing an emergency blood shortage, according to an organization press release. Since July 1, the Red Cross national blood supply has fallen by more than 25%, and blood donors of all types, especially those with type O blood, are urged to give as soon as possible to help patients receive lifesaving medical care, the release noted. Heat impacted more than 100 blood drives in July in nearly every state where the Red Cross collects blood, compounding other seasonal obstacles to blood donation, such as travel and summer activities, it explained. Together these factors contributed to a shortfall of more than 19,000 blood donations in July.