Yield and future issues of nucleic acid testing.
Despite the much lower actual yield than that estimated for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) nucleic acid testing (NAT)-only positives in the USA and Germany, look-back procedures have revealed that no HCV transmission has occurred in Germany since the introduction of NAT. This indicates sufficient sensitivity of the pool-PCR approach. The slow ramp-up of hepatitis B virus (HBV) however, may require a different approach. It has been shown in Germany that the pooling of samples followed by virus enrichment results in a significant yield. Single donation testing for HBV would not increase the yield, because virus enrichment from mini-pool results in a similar sensitivity to that of single donation testing. Both strategies may be useful for extending future NAT to HBV screening. New candidate viruses for NAT are Parvo B19 and hepatitis A virus (HAV) because of their extreme resistance to inactivation procedures. Their low pathogenicity and epidemiologic characteristics, however, make them candidate viruses only for pooled source plasma. The main future issues of NAT will be related to the automation of pooling, extraction and amplification as a single homogeneous process. Depending on the throughput, automated single donation NAT as demonstrated by the 'Tigris' system may be an option, as far as all transfusion-relevant viruses will be included. In the near future high throughput systems will rely on pooled donor samples, most probably in conjunction with efficient enrichment procedures. For these systems, automation of the extraction and amplification process will be one of the first steps. These procedures will also limitthe costs of NAT and keep it available for use with future candidate viruses.
Roth
W K
WK
Institute of Transfusion Medicine and Immunohematology, Red Cross Blood Transfusion Service Hesse, Frankfurt am Main, Germany. wroth@bsdhessen.de
Seifried
E
E
D001685:Biological Factors / Q000097:blood / Q000302:isolation & purification; D003365:Costs and Cost Analysis; D004279:DNA, Viral / Q000097:blood*; D005544:Forecasting; D005858:Germany; D006678:HIV / Q000302:isolation & purification; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control / Q000635:transmission; D006509:Hepatitis B / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control / Q000635:transmission; D006518:Hepatitis Viruses / Q000235:genetics / Q000302:isolation & purification; D006525:Hepatitis, Viral, Human / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control / Q000635:transmission; D006564:Herpesviridae / Q000235:genetics / Q000302:isolation & purification; D006566:Herpesviridae Infections / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control / Q000635:transmission; D006801:Humans; D008403:Mass Screening / Q000191:economics / Q000379:methods* / Q000706:statistics & numerical data; D010322:Parvoviridae Infections / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control / Q000635:transmission; D016732:Parvovirus B19, Human / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000191:economics; D012367:RNA, Viral / Q000097:blood*; D012449:Safety; D014481:United States; D014766:Viremia / Q000175:diagnosis* / Q000821:virology
D001685:Biological Factors; D004279:DNA, Viral; D012367:RNA, Viral