From 1987 to the present, the Seroconversion Surveillance Project has provided the means by which to monitor the risk of transmission of human immunodeficiency virus (HIV) by clotting factor concentrates. One hundred thirty‐one hemophilia treatment centers in the United States are contacted regularly, and data on HIV testing of patients are collected. To date, 4366 (46.0%) of 9496 patients have been reported to be seropositive, and 37 new seroconversions have been identified. Nine of these have met the Centers for Disease Control criteria for seroconversion while the patient was taking factor concentrate. None of the nine seroconversions were due to concentrates that had been treated to inactivate viruses and made from plasma that had been tested for HIV antibody. These results indicate that there is a high prevalence of seropositivity in affected patient groups, but that the risk of HIV infection from currently available clotting factor concentrates is extremely low.

Fused-silica open-tubular capillary columns coated with high-molecular-weight polyethylene glycols of different origins have been evaluated. The chromatographic behaviour below and above the solid-liquid transition temperature was studied through measurements of the column efficiency, resolution and capacity factors as a function of the column temperature and the nature of the solutes.