ABSTRACT
BACKGROUND@#Ever since the Korean Red Cross adopted HCV NAT for blood donor screening in 2005, HCV NAT reactive donors have been identified every year. The identification of the clinical features for these HCV NAT reactive donors may be helpful for the treatment and prevention of HCV infection.@*METHODS@#We analyzed HCV NAT reactive samples to examine the distribution of HCV RNA genotypes and the quantitative values of 128 and 47 HCV NAT reactive samples in 2007 and 2017, respectively.@*RESULTS@#The dominant genotype of the HCV NAT reactive donors was 1b showing 50.0% (64/128) in 2007 and 44.7% (21/47) in 2017. The genotype 2a was the second most dominant at 40.6% (52/128) in 2007 and 40.4% (19/47) in 2017. The mean titers of HCV RNA were 3.17×106 IU/mL in 2007 and 2.61×106 IU/mL in 2017. More than 90% of the donors showed a range of more than 1,000 IU/mL for the HCV RNA titer. There was no difference of quantitative values in the different genotypes.@*CONCLUSION@#In this study, the distribution of HCV RNA genotypes in Korean blood donors showed a similar pattern compared to that of the general population. There was no correlation between the quantitative values and genotypes in the HCV NAT reactive blood donors, and there was no significant variation in the distribution of HCV RNA genotypes of the HCV NAT reactive donors between 2007 and 2017. Yet it is thought that the characteristics of HCV NAT reactive samples in other years have to be analyzed to achieve more significant results.
ABSTRACT
BACKGROUND: The risk of transfusion-transmissible infections (TTIs) of HBV, HCV, and HIV in Korea has been reduced significantly by strengthening the blood safety policies. On the other hand, the risk of TTI still exists due to the diagnostic window period or viral variants. METHODS: The residual risks of TTI of HBV, HCV, and HIV were calculated from July 1, 2012 to June 30, 2018 by dividing the data into two year sets. The residual risk was conducted by separating the donors who donated only once and those who donated more than once during each period. RESULTS: In the first two years, the residual risks of HBV, HCV, and HIV were calculated to be 17.54/106, 0.42/106, and 0.30/106 respectively. The residual risk of HBV and HCV over the last two years was calculated to be 9.41/106 and 0.27/106, showing a tendency to decrease with time. On the other hand, the residual risk of HIV over the last two years was calculated to be 0.29/106, showing no significant difference. The residual risk in the donors who donated only once was higher than that in the donors who donated more than once during each period. CONCLUSION: The real transfusion-transmitted infection can be different from the estimated residual risk in this study because this study was based on the thesis that all NAT-reactive blood components cause infection. Because the residual risk of HBV is higher than HCV and HIV, it was considered that the safety measures for the HBV need to be improved continuously.
Subject(s)
Humans , Blood Safety , Hand , HIV , Korea , Tissue DonorsABSTRACT
HBV core antibody and surface antibody test are currently conducted for those donors showing non-discriminated reactive (NDR) results on a nucleic acid amplification test (NAT) as a blood donor screening assay. It is necessary to investigate the relationship with HCV or HIV in the donors showing NDR results. From June 12th, 2012 to December 31st, 2018, 0.05% (9,020/17,798,461) donors showed NDR results on a NAT. Among the donors showing NDR results, 17 and 18 donors showed positive results on serological assay of HCV and HIV, respectively. 23 donors with NDR results showed positive results on the serological assay or NAT for HCV or HIV on the following donation. Further study and more accumulated data are required because it may be difficult to find the cause of NDR results by the current serological assay that is used for screening blood donors.
Subject(s)
Humans , Blood Donors , HIV , Mass Screening , Nucleic Acid Amplification Techniques , Tissue DonorsABSTRACT
BACKGROUND: Since December 15 2017, donors showing a non-discriminated reactive (NDR) result in the nucleic acid amplification test (NAT) have been temporarily deferred and anti-HBc and anti-HBs assays as additional tests were performed. Donors with an anti-HBc reactive result and less than 100 IU/L of anti-HBs could not be released and can request a reentry test after more than six months. This study considered the effects of additional tests for NDR donors by analyzing the reentry test results in donors not released in the additional test. METHODS: This study examined the results of the additional test for NDR donors from January 2017 to September 2018 and the reentry test of the donors not released in the additional test. RESULTS: NAT was conducted on 4,706,051 blood donors over the period and 2,545 (0.05%) of them showed NDR. A total of 656 (25.8%) of the NDR donors were not released in the additional test. Among them, 246 donors requested a reentry test; 222 (90.2%) donors were not reentered, and 23 (10.4%) showed HBV NAT reactive results in the reentry test. Among the remaining 24 reentered donors, 2 donors (8.3%) showed anti-HBc nonreactive results in the reentry test and 22 donors (91.7%) showed higher than 100 IU/L of anti-HBs. CONCLUSION: The follow-up of NDR donors may be significant because some donors showed different results between screening test and reentry test. In addition the effectiveness of the introduction of additional tests for the NDR donors has been proved to be effective.
Subject(s)
Humans , Blood Donors , Follow-Up Studies , Mass Screening , Nucleic Acid Amplification Techniques , Tissue DonorsABSTRACT
BACKGROUND: A nucleic acid amplification test was adopted to detect transfusion-transmitted infectious agents. In the case of HTLV, however, there was no internal control (IC) because the laboratory developed polymerase chain reaction (laboratory-developed PCR) was used. In this study, noncompetitive IC was constructed for the laboratory-developed PCR of HTLV and the effectiveness was compared with the competitive test that was constructed in a previous study. METHODS: As a competitive IC, plasmid DNA, including the primer recognition sequence for the amplification of the HTLV pX region, was constructed. As a noncompetitive IC, an additional primer was constructed for the amplification of the housekeeping gene, the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene. The performance of the competitive and noncompetitive IC was verified and compared using 10 HTLV positive samples and 10 negative samples. In addition, the detection limits in the assay adopting competitive IC and noncompetitive IC were compared. RESULTS: In the case of competitive IC applications, all 10 positive samples were positive and all 10 negative samples were negative. In the case of noncompetitive IC applications, however, one positive sample was not detected. The detection limit of the assay using competitive IC was 100 pg and that of the assay using noncompetitive IC was 1 ng. CONCLUSION: Although the manufacturing processes is not required using noncompetitive IC, the adoption of competitive IC is more effective to ensure the assay results because the ability of detection of the assay adopting competitive IC was better than that using noncompetitive IC.
Subject(s)
DNA , Genes, Essential , Glyceraldehyde 3-Phosphate , Limit of Detection , Nucleic Acid Amplification Techniques , Oxidoreductases , Plasmids , Polymerase Chain ReactionABSTRACT
BACKGROUND: If donors who were deferred due to the reactivity or grey zone in HBV surface antigen (HBsAg) assay want to donate blood again, they need to pass reentry tests. On the other hand, approximately half of the donors who are subject to the reentry tests cannot be reentered. This study examined the association between the sample to cutoff (S/Co) value of the HBsAg assay and the final results of the reentry test. METHODS: This study analyzed the S/Co values of the HBsAg assay and the final results of the reentry tests for the 3,947 donors from January 2008 to December 2017 using the database of Blood Information Management System of the Korean Red Cross. RESULTS: 1,767 donors (44.8%) were not reentered among 3,947 deferred donors. Among 1,585 donors showing ≥10 of the S/Co value in the HBsAg screening test, 1,542 donors (97.3%) were not reentered. The additional reentry tests were performed on 120 donors who were not reentered in the first reentry test; 98 donors (81.7%) were still not reentered. Overall, 4.6% of the donors showing a grey zone in the HBsAg assay were not reentered. CONCLUSION: The reentry test needs to be restricted for the deferred donors showing a more than 10 S/Co value. The application of the grey zone of current HBsAg assay will need to be continued to enhance the HBV-related blood safety.