Introduction of NAT-testing for infections for screening blood donors in Republic of Kazakhstan

Aim. To evaluate the effectiveness of NAT-screening (nucleic acid amplification technologies) for infections in blood donors in Kazakhstan. Methods. Statistical data of blood donors screening examinations in the Republic of Kazakhstan in 2012-2014 were evaluated. Results. In 2014, the number of examined donors increased by 3.4% compared with 2012. The number of deferrals due to positive screening results for serological markers decreased by 10.9%, while the share of such donors decreased by 13.8% [p <0.01; odds ratio (OR) - 0.86, 95% confidence interval (CI 95%) - 0.83-0.88); χ2=136.76]. In 2014, 100% of donations were screened using NAT-testing (312,510 donors). Most of the NAT-screening in Kazakhstan is performed using closed automated systems. In 2012, 1 Blood Center conducted a polymerase chain reaction screening by open circuit polymerase chain reaction systems, in 5 blood centers polymerase chain reaction was performed with manual sample preparation. In 2014, the number of deferrals due to positive NAT-testing results has increased by 44.3%, the share of such donors - by 38.7% (p <0.01; OR=1.39, 95% CI=1.15-1.67); χ2=11.82). Seronegative NAT-positive samples were discovered according to the results of discriminant test, including human immunodeficiency virus - 2 (0.8%) samples, hepatitis B virus -182 (73.4%), hepatitis C virus - 60 (24.2%), negative result - 4 (1.6%). Conclusion. The introduction of screening NAT-testing of donated blood prevented transfusion of blood infected with: human immunodeficiency virus - 1 in 150,000 donations, hepatitis B virus - 1 in 1.650 donations, hepatitis C virus - 1 in 5,000 donations.

NAT, blood service, donor, infection, NAT, polymerase chain reaction, hepatitis, HIV