Significance of nucleic acid testing for transfusion safety in a country without deferral of men who have sex with men: Epidemiology of <scp>HIV</scp> among Polish blood donors and residual transfusion‐transmission risk, 2005–2023

BACKGROUND AND OBJECTIVES: In Poland, human immunodeficiency virus (HIV) prevalence in the general population is lower than in other developed countries, and men who have sex with men (MSM) are not deferred from donating blood. The aim of the study was to analyse the epidemiology of HIV in Polish blood donors after the introduction of mandatory HIV RNA screening (for the period 2005-2023). MATERIALS AND METHODS: HIV test results using anti-HIV (third- or fourth-generation tests) and HIV RNA using transcription-mediated amplification or PCR methods (individual donations [IDT]-minipool [MP] 24) were analysed in 23,215,295 donations from 11,179,429 donors. RESULTS: The mean infection rate per 100,000 donors was 6.48 for all and 6.22 and 0.26 for seropositive and seronegative infections, respectively. Seronegative infections occurred 5.8 (1.4-25)-fold more often in repeat donors than in first-time donors. Almost 25% of HIV-infected donors donated blood within 100 days since HIV acquisition (analysis of Fiebig scale). In four donors, discordant results were identified, indicating elite controller infection, antiretroviral treatment (ART) or HIV prophylaxis and vaccination. No HIV transmission by transfusion was recorded in look-back, and the residual risk for red blood cells (RBCs) (Weusten model) dropped from 0.129 for MP24 at the beginning to 0.019 for MP6 and 0.0051 per million units for - Individual donation-nuclec acid testing, recently. CONCLUSION: The HIV incidence in blood donors in Poland, compared to other developed countries, was high, despite the low rates reported by epidemiological surveillance. NAT is an effective addition to serological screening in reducing residual risk of HIV transmission by possible test-seeking blood donors in Poland.