Re-engineering the medical assessment of blood donors in South Africa: The balance between supply and safety

Background: The balance between ensuring blood donor and recipient safety while maintaining a sufficient blood supply can be affected by excessive deferral of blood donors. In 2018, a biannual regulatory review of donor eligibility criteria provided the South African National Blood Service (SANBS) the opportunity to review the existing criteria. Changes to these criteria were implemented in April 2019 after an extensive review.

Study design and methods: We conducted a cross-sectional study of SANBS whole-blood donor presentations to determine the impact of the changed donor eligibility criteria on deferrals and blood safety. We compared donor presentations, deferrals, and HIV-positive cases for the 12-month period (April 2019-March 2020) after the implementation of the updated donor eligibility criteria to those of the previous year.

Results: Of the 2,112,917 donor presentations, 51.1% (1079506) occurred in the post-implementation study period. Overall, deferrals decreased from 18.6% to 14.5%, whereas HIV-positive donations increased by 0.03%. A multivariable logistic regression analysis adjusted for sex, age, geographical location, donor, and clinic type showed significantly lower odds of deferral (OR 0.70; 95% CI: 0.69-0.70) and greater odds of HIV-positive cases in the study period than those in the control period (OR 1.17; 95% CI: 1.10-1.25).

Conclusion: We confirmed that the change in donor eligibility criteria was associated with a decrease in deferrals and an increase in the country's blood supply. The impact of the increased number of HIV-positive donations on blood safety in a country performing individual donation nucleic acid amplification testing requires further investigation.