Sensitivity of two hepatitis B virus, hepatitis C virus (HCV), and human immunodeficiency virus (HIV) nucleic acid test systems relative to hepatitis B surface antigen, anti-HCV, anti-HIV, and p24/anti-HIV combination assays in seroconversion panels.
BACKGROUND
Accurate determination of the infectious window period (IWP) that remains with individual-donation (ID) or minipool (MP) NAT compared to those with serology assays is essential for residual risk estimations.


METHODS
The relative sensitivity of the Procleix Tigris system (Gen-Probe/Chiron) used in ID-NAT format and cobas s 201 (Roche Molecular Systems) applied in 1:6 diluted samples to mimic six-minipool (MP6) nucleic acid test (NAT) was assessed by quadruplicate testing of five seroconversion panels per marker. A mathematical analysis based on the log-linear increase of viremia in the ramp-up phase, as established with bDNA 3.0 assays enabled estimation of the IWP for human immunodeficiency virus (HIV) and hepatitis B virus (HBV) assays.


RESULTS
The mean IWPs were Tigris HIV RNA 5.5 days, s 201 (1:6) HIV RNA 7.4 days, GenScreen Plus p24/anti-HIV 17.8 days, PRISM anti-HIV 19.0 days, Tigris HBV DNA 20.6 days, s 201 (1:6) HBV DNA 22.6 days, Bio-Rad hepatitis B surface antigen (HBsAg) 37.8 days, and PRISM HBsAg 35.5 days. At estimated 50 percent NAT seroconversion rates, s 201 (1:6) and Tigris showed mean window-period reduction times (WPRTs) of 30.5 to 35.5 days to hepatitis C virus antibody (anti-HCV) assays, 10.4 to 13.5 days to anti-HIV, or combination p24/anti-HIV assays and 12.8 to 17.2 days to HBsAg assays.


CONCLUSIONS
Tigris ID-NAT detected HIV RNA 2 days earlier than s 201 MP6-NAT, but the difference in sensitivity between the two NAT systems was not significant in HBV seroconversion panels. Insufficient seroconversion samples were available for reliable modeling of WPRT in early HCV infection, but 1.4 to 2.0 days could be predicted by translating analytical sensitivity data. Both multiplex NAT systems demonstrate significant WPRTs compared to (combined) antigen and antibody assays.
Assal
Azzedine
A
Etablissement Français du Sang , La Plaine Saint Denis, France. azzedine.assal@efs.sante.fr
Barlet
Valérie
V
Deschaseaux
Marie
M
Dupont
Isabelle
I
Gallian
Pierre
P
Guitton
Cathy
C
Morel
P
P
van Drimmelen
Harry
H
David
Bernard
B
Lelie
Nico
N
De Micco
Philippe
P
D004279:DNA, Viral / Q000097:blood; D006678:HIV / Q000235:genetics*; D016174:Hepacivirus / Q000235:genetics*; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D021141:Nucleic Acid Amplification Techniques; D012367:RNA, Viral / Q000097:blood; D012044:Regression Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods*; D013997:Time Factors; D014766:Viremia / Q000097:blood
D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D012367:RNA, Viral