Human T-cell lymphotropic virus: A simulation model to estimate residual risk with universal leucoreduction and testing strategies in Canada.

BACKGROUND AND OBJECTIVES: In Canada, transfusion transmission risk of Human T-cell lymphotropic virus -I/II (HTLV) is addressed by universal leucoreduction and universal antibody testing. We aimed to estimate the risk with the current policy, if testing only first-time donors and if testing were stopped. MATERIALS AND METHODS: Monte Carlo simulation was employed to estimate the proportion of red cell concentrate, random donor platelet and apheresis platelet units that would be released into inventory in each scenario (10 billion donors each). The model estimated the number of HTLV-positive donations not intercepted by testing, randomly assigned the number of HTLV particles/100 leucocytes using proportions from published data and randomly selected a postleucoreduction leucocyte count from quality control data. Units were considered infectious if ≥9 × 104 copies of HTLV provirus. RESULTS: With universal leucoreduction in place, the residual risk of releasing an HTLV potentially infectious unit with universal testing was 1 in 1·2 billion units (0, 1 in 55·9 million), with testing only first-time donors 1 in 7·1 million (0, 1 in 1·05 million) and with no testing 1 in 1·0 million (0, 1 in 178 600). The efficacy of leucoreduction was >99·5% (lower bound 95·7%) for all scenarios. CONCLUSION: With universal leucoreduction in place, switching from universal testing to testing first-time donors would incur very low risk.

Blood donation and blood transfusion in Spain (1997 - 2007): the effects of demographic changes and universal leucoreduction.

BACKGROUND AND OBJECTIVE: As epidemiological information is useful in planning the provision and assessing the efficiency of product use, we reviewed Spanish data on population, blood donation and blood component transfusion from 1997 to 2007, and the possible effect of universal leucoreduction. METHODS: Data on the Spanish population were obtained from the National Institute of Statistics, whereas data on blood donation and blood component transfusion were acquired from the Spanish Ministry of Health. RESULTS: During the study period, the Spanish population increased by 5.6 million persons (14.4%), and blood donation by 28.1%, although the amount of red blood cells (RBC) obtained increased by only 21.5% whereas RBC transfusions increased by 28.3%. The RBC transfusion rate was significantly higher after the implementation of universal leucoreduction (2002 - 2006) than during the pre-leucoreduction period (1997 - 2001) (difference = 2.54 units/1,000 population/year; 95%CI 1.81 - 3.27; P<0.001). We also observed statistical ly, but not clinically, significant differences for platelet and plasma transfusions. CONCLUSION: The increase observed in the RBC transfusion index after implementation of universal leucoreduction may have been due to a reduction of the haemoglobin content in the RBC units. Our data on blood use do, therefore, seem to add to the case against universal leucoreduction, which has led to an incremental cost for unknown, but probably slight, benefits for patients.