Istituto Superiore di Sanità Laboratory of Immunology External quality assessment for detection by NAT of the six major HCV genotypes M Wirz*, GM Bisso*, K Cristiano*, G Gentili*, C Mele*, G Pisani*, J Saldanha° * Laboratory of Immunology,Istituto Superiore di Sanità, Rome, Italy ° Canadian Blood Services, Ottawa, canada

Istituto Superiore di Sanità Laboratory of Immunology AIM OF THE EQA/4 STUDY Assessing the proficiency of blood products manufacturer and blood centres in detecting by NAT the six major HCV genotypesAssessing the proficiency of blood products manufacturer and blood centres in detecting by NAT the six major HCV genotypes 31 laboratories participating in the study from Argentina, Austria, Australia, Canada, Germany, Italy, Switzerland, UK and USA 8 blood product manufacturers8 blood product manufacturers 2 diagnostic kits manufacturers2 diagnostic kits manufacturers 21 blood centres21 blood centres

Istituto Superiore di Sanità Laboratory of Immunology PANEL COMPOSITION 16 coded samples 12 positive samples, containing genotypes 1-6 with a nominal concentration of 100 IU/mL12 positive samples, containing genotypes 1-6 with a nominal concentration of 100 IU/mL –HCV RNA ISS 0498 (genotype 1) (Vox Sang 2000; 78: ) –HCV genotypes 2-6 kindly provided by John Saldanha (Vox Sang 2003; 84: 20-27) 4 negative replicates4 negative replicates Amplicor (19 labs), TMA assay (5 labs), In-house (7 labs) NAT METHODS

Istituto Superiore di Sanità Laboratory of Immunology RESULTS Genotype (100 IU/mL) Sample code Positive/tested (%) 1 9 and 12 60/60 (100) 2 4 and 7 60/60(100) 3 2 and 13 60/60(100) 4 1 and 16 58/60(96.7) 5 5 and 11 59/60(98.3) 6 3 and 14 59/60(98.3) negative 6, 8, 10, 15 2/120(1.7)

Istituto Superiore di Sanità Laboratory of Immunology DISCREPANT RESULTS GenotypeSample codeFailing Lab Neg

Istituto Superiore di Sanità Laboratory of Immunology CONCLUSIONS This study represents the first one that included all the six major HCV genotypes This study represents the first one that included all the six major HCV genotypes Overall results can be considered satisfactory Overall results can be considered satisfactory As the ability to detect all HCV genotypes is of crucial importance, next EQA studies should continue to include all six major HCV genotypes As the ability to detect all HCV genotypes is of crucial importance, next EQA studies should continue to include all six major HCV genotypes