Do all blood banks notify donors if their blood tests positive for a disease?

They should.: Donors are usually notified if the blood they gave is positive for a disease, like hepatitis b surface antigen, antibody to hepatitis c, antibody to hiv, usually subtypes 1 and 2, and serologic test for syphilis as recommended by the world health organization. Blood is also tested for diseases, like stds. Donated blood that is positive is discarded unless it is autologous as that is given back.