Revisiting Donor Screening Protocols in Polish Milk Banks: A Pilot Study Supporting the Update of Approaches to Screening Donors with CMV Infection

PURPOSE Cytomegalovirus (CMV) seroprevalence in Poland is high among women and represents a substantial proportion of milk donors. European Milk Bank Association (EMBA) does not recommend CMV serological screening of donors; Polish milk banks currently require CMV serological testing at recruitment. We evaluated donor screening protocols to align Polish milk bank policies with European SoHO classification by assessing concordance between CMV serostatus-based donor screening and CMV viral DNA detection in breast milk. METHODS Twenty lactating mothers were recruited (mean maternal age 30.75 years; mean postpartum time 3.06 months): Donors underwent CMV IgG and IgM serological testing at recruitment. Three milk samples were collected at monthly intervals following a 0-1-2 scheme. Sixty breast milk samples were assessed using qualitative PCR to detect CMV viral DNA. The concordance of CMV presence in serology and an alternate qualitative PCR method was compared using real-time PCR as the reference method. RESULTS CMV viral DNA was detected by real-time PCR in 35% of donated milk samples (7/20), with most demonstrating declining viral shedding. The IgM model showed 0% sensitivity, whereas qualitative PCR achieved 82.6% sensitivity. Qualitative PCR had a higher negative predictive value (95.1% vs 68.3%) and overall accuracy (90.0% vs 68.3%). CONCLUSION CMV serology-based screening demonstrated limited concordance with CMV viral DNA detection in breast milk, while qualitative PCR-based classification more closely reflected viral DNA presence, it incurred higher operational costs, highlighting biological and operational trade-offs in CMV screening strategies consistent with current EMBA guidance.