Screening technologies aimed at identifying such transfusion transmissible infections (TTI) as hepatitis B and C, HIV-1,2 and syphilis have been developing and this has resulted in increased safety of applied hemotherapy. Our research goal was to analyze detection of infectious markers in donors of the FMBA Blood Center over five years. We examined 167,389 samples of donor blood taken from 53,093 donors of blood and its components by the FMBA Blood Center over the period from 2015 to 2019. Over the whole analyzed period, we detected 1453 infectious-positive samples taken from 1235 donors. Average long-term quantity of detected hepatitis C markers equaled 78.6 ± 9.4; hepatitis B, 49.8 ± 8.2; syphilis, 66.2 ± 16.8; HIV, 52.8 ± 13.2. We also analyzed detected of TTI markers in long-term dynamics and established an ascending trend in a number of syphilis markers (the growth rate was 3.2), hepatitis B (the growth rate was 2.5), and a descending trend in hepatitis C markers (the decrease rate was 3.3) as well as HIV markers (the decrease rate was 1.7). This decrease rate in detection of HIV markers (fall by 1.7) occurred both among first-time and regular donors. At the same time, we revealed growing detection of syphilis markers both among first-time donors where it grew by 3.6 and among regular ones, by 1.4. Frequency of infection markers was higher among first-time donors than among regular ones as per syphilis markers, 2.351 (95 % CI: 1.862–2.938), p < 0.00001; hepatitis B markers, 2.111 (95 % CI: 1.622–2.763), p < 0.00001; hepatitis C markers, 2.107 (95 % CI: 1.708–2.609), p < 0.00001; and HIV, 2.471 (95 % CI: 1.9–3.238), p < 0.00001. Over the last 5 years, there was a descending trend in detection of transfusion transmissible infections among donors regarding HIV and viral hepatitis C excluding tests aimed at detecting syphilis and viral hepatitis B markers.

Introduction. The introduction of screening testing for antibodies to the hepatitis B virus nuclear antigen (anti-HBcore) is designed to prevent the procurement of donated blood from individuals with the latent (occult) form of viral hepatitis B, in which surface HBsAg is not identified. Aim – to evaluate the frequency of anti-HBcore markers’ occurrence in donors under the current regulatory and legal framework. Materials and methods. This retrospective observational study was conducted with a follow-up period of one year among blood donors of the Blood Center (BC) of the Federal Medical-Biological Agency. The screening study for anti-HBcore in blood donors and its components was selective in accordance with the requirements of Appendix № 4 of Order № 1166n of October 28, 2020 of the Ministry of Health of Russia. Results. During the study period, the BC was visited by 17,180 donors who donated blood and its components 35,840 times. There were 181 anti-HBcore tests (0.5 % of all blood samples) in 178 unique donors of blood and blood components (1.03 % of all donors). There were 14 positive, 2 questionable and 166 negative results on anti-HBcore tests. The probability of finding a positive result depending on the conditions was 9 % (7.3–14.7 %). There were no statistically significant differences in the detection of anti-HBcore in primary versus regular donors (OR = 2.539; 95% CI: 0.7321–8; p = 0.13), as well as for male donors compared with female donors (OR = 2.448; 95% CI: 0.7141–11.11; p = 0.17). 86.7 % of donors with a positive test for anti-HBcore previously had no signs of viral hepatitis B disease, the presence of questionable HBsAg was not detected, i. e. these cases may be associated with an occult form. Donors who did not previously have questionable results for various bloodborne infections during their donor career had a slightly higher probability of detecting a positive anti-HBcore test compared to donors who previously had these questionable results (OR = 1.24; 95% CI”: 0.42–3.69; p = 0.69). During the period of the donor career, 233 donations of blood and its components were made by donors with a positive result for anti-HBcore, 468 units of donor components were received, of which 365 units were given to medical institutions. Conclusion. The probability of obtaining a positive test for anti-HBcore in the current regulatory environment is random and does not depend on the results of other infectious markers testing. It is recommended to perform anti-HBcore testing with each donation of blood and blood components.