[Multiplex nucleic acid testing: development and applications]

Advances in viral nucleic acid amplification and detection techniques have resulted in molecular diagnostics becoming key procedures in viral infection characterization. Molecular assay development applied to clinical diagnostic and transfusion safety is essentially limited by cost. To overcome this limitation, multiplex nucleic acid testing (NAT) assays allowing simultaneous detection and eventually direct identification of several viral genomes have been developed using recent technical improvements in genomic amplification technologies. Optimization may prove difficult, but commercial and in-house multiplex NAT assays have been successfully applied to large-scale screening of blood donations for HBV, HCV and HIV-1, improving transfusion safety by reducing the pre-seroconversion window period. They showed high sensitivity and specificity, and may decrease operating costs and testing turnaround time. Multiplexing has the potential to improve blood safety in highly endemic resource-limited areas in a cost-effective way when associated with other costreducing procedures such as plasma pooling and pre-donation serological screening.