It is not possible to contract HIV, the virus that causes AIDS, by donating blood. Each needle used in the procedure is sterile and is disposed of after a single use. A. People in good health who weigh at least 110 pounds can donate a unit of blood as often as every eight weeks. There are many places where donations can be made. Bloodmobiles travel to high schools, colleges, churches, and other community organizations.
People can also donate at community blood centers and hospital-based donor centers.
Many people donate at blood drives at their workplace. Although most blood is donated as whole blood, it is also possible to donate only a portion of blood using a technique called apheresis. Blood is drawn from the vein of a donor into an apheresis instrument, which separates the blood into different portions by centrifugation. By appropriately adjusting the instrument, a selected portion of the blood, such as the platelets, can be recovered, while the rest of the blood is returned to the donor either into the same vein or into a vein in the other arm. This process takes more time than whole blood donation, but the yield of platelets is much greater.