Practical limitations of convalescent plasma collection: a case scenario in pandemic preparation for influenza A (H1N1) infection

BACKGROUND: To ensure a good preparedness for pandemic influenza A (H1N1), a study was conducted to investigate clinical effectiveness of hyperimmune intravenous globulin (H-IVIG) prepared from convalescent plasma donated by recovered patients. This article reports on the outcome of the collection phase of the study. STUDY DESIGN AND METHODS: Starting on August 26, 2009, all confirmed patients aged between 18 and 55 years were invited for participation into the study and screen for plasma donation eligibility. Effective September 17, 2009, those who were unwilling to consider screening for plasma were asked to donate whole blood. Plasma collected or separated from whole blood had to demonstrate sufficient neutralization antibodies titers of 40 or more before being channeled for H-IVIG production. RESULTS: By October 31, 2009, a total of 9101 persons were successfully contacted. A total of 1309 screening and 619 whole blood donation appointments were made. In the former 786 (60.0%) attended screening but only 301 could donate plasma by apheresis because of failure to meet blood donation eligibility criteria, failed laboratory tests, insufficient neutralization antibody titers, and inability to make the apheresis appointment. For those who opted for whole blood donation, 379 (61.2%) had attended and donated. A total of 276 L of convalescent plasma with sufficient neutralization antibodies titers was collected for H-IVIG production. DISCUSSION: The study highlighted a number of practical limitations in convalescent plasma collection programs and plasmapheresis is always the preferred mode of collection. It provided valuable learning experience for the blood transfusion service in future planning when large-scale collection is required.