Residual risk of transfusion-transmitted viral infections in Shenzhen, China, 2001 through 2004
Guifang Shang1, Clive R Seed, Fei Wang
1Blood and Tissue Unit, Therapeutic Goods Administration, Woden ACT, Australia.
Background:
There are no current estimates of the residual risks of transmission by blood of hepatitis B virus (HBV) or hepatitis C virus (HCV) and human immunodeficiency virus (HIV) in China. Such estimates are an essential prerequisite to monitoring and improving transfusion safety as well as supporting evidence based assessment of the value of implementing new screening interventions.
Study Design And Methods:
Viral screening data for donors from Shenzhen, China, for the period 2001 to 2004, were retrospectively analyzed. The data were applied to a published model to estimate the residual risk of transmitting HIV, HBV, and HCV by blood transfusion in Shenzhen, as well as to assess the residual risk reduction value of various new tests.
Results:
The point estimates for the combined 2003 and 2004 period calculate as 1 in 17,501 for HBV, 1 in 59,588 for HCV, and 1 in 903,498 for HIV. The predicted yield for improved hepatitis B surface antigen (HBsAg) assays, minipool (MP) nucleic acid testing (NAT), and individual-donation (ID) NAT was 6.9, 9.5, and 28.3 per million donations, respectively. The predicted yield for implementing a fourth-generation HCV (antigen-antibody) or MP NAT assay was 13.4 or 14.7 per million donations, respectively. For HIV, the predicted yield for implementing a fourth-generation HIV (antigen-antibody) or MP NAT assay was markedly smaller, 0.25 or 0.65 per million donations, respectively.
Conclusions:
Relative to that reported for Western blood systems, the prevalence and the residual risk of HBV and HCV are high, whereas HIV is comparable. Pending a formal cost-effectiveness study for NAT, implementing improved HBsAg and combination HCV antibody-antigen assays in Shenzhen would markedly reduce the residual risk.