The most common source of blood is from volunteers in the general public. This kind of donation is also called homologous blood donation.
Many communities have a blood bank at which any healthy person can donate blood. This blood is tested to see if it matches yours.
You may have read about the danger of becoming infected with hepatitis, HIV, or other viruses after a blood transfusion. Blood transfusions are not 100% safe. But the current blood supply is thought to be safer now than ever. Donated blood is tested for many different infections. Also, blood centers keep a list of unsafe donors.
Donors answer a detailed list of questions about their health before they are allowed to donate. Questions include risk factors for infections that can be passed on through their blood, such as sexual habits, drug use, and current and past travel history.