HIV transmission between two adolescent brothers with hemophilia.

In July 1992, the National Hemophilia Foundation and CDC received a report from a hemophilia-treatment center of a 19-year-old man with hemophilia (patient 2) who recently had seroconverted for antibody to human immunodeficiency virus (HIV). This report summarizes the findings of an investigation by CDC and state and local public health officials, which determined he was infected with a strain of HIV nearly identical to that in his previously infected older brother (patient 1).