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Follow-up program for blood donors with unconfirmed screening results reveals a high false-positive rate in Dalian,
Xuelian Deng1, Liang Zang1, Xinmei Wang1
1Dalian Blood Center, Dalian, China.
Insights
A follow-up program for deferred blood donors in China identified a high rate of false-positive screening results. Reevaluating donor screening strategies is recommended to improve accuracy and donor reentry.
Area of Science:
- Transfusion Medicine
- Infectious Disease Screening
- Public Health
Background:
- Chinese blood donors with unconfirmed screening results are permanently deferred.
- A follow-up program was implemented in Dalian, China, to improve management of these donors.
Purpose of the Study:
- To investigate the implementation and performance of a donor follow-up program.
- To assess the accuracy of initial screening and identify true infection status.
Main Methods:
- Tested 411,216 donations for HBV, HCV, HIV, and TP using serological and nucleic acid testing (NAT).
- Developed a follow-up procedure for deferred donors, including potential NAT yield and non-reactive cases.
- Evaluated donors using alternative serological assays and individual donation NAT re-testing.
Main Results:
- Identified HBV, HCV, HIV, and TP in 0.12%, 0.09%, 0.04%, and 0.49% of donations, respectively.
- Follow-up testing refined infection status in 78.0% of deferred donors.
- Documented false reactivity in 61.9%, primary acute infections in 3.3%, and occult HBV infection (OBI) in 12.8% of participants.
Conclusions:
- The high false-positive rate in initial screening necessitates reevaluation of current strategies.
- The study supports considering donor reentry based on refined follow-up testing.
- Improved donor management and screening accuracy are crucial for blood safety.
Background:
Chinese blood donors with unconfirmed serological and/or molecular screening results are deferred permanently. This study investigated the implementation and performance of a follow-up program aiming to improve the notification and management of deferred donors in Dalian, China.
Study Design And Methods:
From January 2013 to February 2018, 411,216 donations were tested for HBsAg, anti-HCV, anti-HIV/HIV antigen, and antibodies to Treponema pallidum. HBV, HCV, and HIV nucleic acid testing (NAT) was performed in mini-pools of six or in individual donations (IDs). Reactive donations were evaluated further with alternative serological assays and ID-NAT re-testing. A follow-up procedure was developed to evaluate a subset of deferred donors that were either potential NAT yield cases, serology non-reactive and NAT non-repeated reactive (NRR), or serology NRR irrespective of NAT result.
Results:
Serological and molecular routine, plus supplemental testing, identified HBV, HCV, HIV, and TP in 503 (0.12%), 392 (0.09%), 156 (0.04%), and 2041 (0.49%) donations, respectively. Overall, 683 of 4156 (16.4%) eligible donors and 205 donors deferred prior 2013 participated in the program. They included 664 serology NRR and 224 NAT yield cases, and 58.8% repeat donors. All markers combined, follow-up documented false reactivity, primary acute infections, and OBI in 61.9% (550/888), 3.3% (29/888), and 12.8% (114/888) of these donors, respectively. Isolated anti-HBc or anti-HBs reactivity was observed in 22% of cases.
Conclusion:
Follow-up testing refined infection status in 78.0% (693/888) of deferred donors with unconfirmed screening results. This high false-positive rate encouraged to reevaluate the current screening strategies and to consider donor reentry.
