AbstractSince exposure to blood products occurs on a daily basis during hemapheresis, the acquired immunodeficiency syndrome (AIDS) epidemic has a serious impact both for patients undergoing apheresis procedures as well as for health professionals working in the field. We studied serum samples from 110 patients who underwent therapeutic plasmapheresis for a variety of diseases not related to AIDS for the presence of antibodies to human immunodeficiency virus (HIV). Exchange fluids used in the majority of the patients were plasma protein fraction and 5% human albumin. Four patients received only fresh‐frozen plasma. Fifty‐five patients also received IV gammaglobulin. The follow‐up period exceeded 24 months. All patients who did not belong to any known high‐risk group for AIDS were negative for HIV antibodies prior to treatment and remained negative at last follow‐up. Seven patients were homosexual men. All seven were seropositive prior to plasmapheresis and remained so throughout the treatment period.Seven health professional working in a busy haemapheresis unit were followed for 2 1/2 years. All remain HIV seronegative with normal immune function.These data indicate that transmission of HIV is unlikely through haemapheresis p