Related Experiment Video
Updated: Apr 25, 2026
VirWaTest, A Point-of-Use Method for the Detection of Viruses in Water Samples
Published on: May 11, 2019
What is the meaning of a nonresolved viral nucleic acid test-reactive minipool?
Lunan Wang1, Le Chang, Yunzheng Xie
1National Center for Clinical Laboratories, Beijing Hospital, Beijing, China.
Background:
This study aimed at analyzing the prevalence of hepatitis B virus (HBV) DNA among hepatitis B surface antigen (HBsAg)-negative donations by cobas TaqScreen MPX test (Roche Molecular Systems) and discussing the meaning of a reactive minipool (MP) that does not resolve to an individual donation (ID)-reactive result.
Study Design And Methods:
Nucleic acid amplification testing (NAT) was performed in 12 Chinese blood centers on 826,044 serologic negative donations in MPs of six. MP-reactive pools that were resolved to ID-reactive donations were confirmed by Roche TaqMan viral load assays. Antibody to hepatitis B surface antigen and antibody to hepatitis B core antigen (anti-HBc) results were also analyzed. Cycle threshold (Ct) values of reactive MPs were analyzed in relation to the probability of pool resolution.
Results:
A total of 1267 of 137,674 pools were reactive, of which 839 donations were reactive by ID-NAT. The MP6 HBV NAT-yield rate lay between 1 in 1600 and 1 in 1000. At MP Ct values equal or below 37, the probability of pool resolution was approximately 80%. The prevalence of anti-HBc in ID-reactive donations was 81%. The proportion of reactive pools that could not be resolved was 36%. The prevalence of anti-HBc in donations implicated in nonresolved MPs was significantly higher than those in nonreactive MPs (48% vs. 37%, p = 0.016).
Conclusion:
The anti-HBc data suggest that approximately 10% of nonresolved MPs contain HBV DNA from a low-viral-load occult carrier. We consider ID-NAT resolution testing in duplicate to minimize HBV transmission risk associated with transfusing nonreactive donations implicated in reactive MPs.
