The 22nd edition of the South African Haemovigilance Report provides an overview of blood product usage and adverse events related to transfusion and blood donation in the country during the 2021 calendar year. A total of 1 265 722 blood products were issued in 2021 with 989 adverse transfusion events being reported, translating into an incidence rate of 78.1/100 000 units transfused. Under-reporting of adverse events is known to be a major challenge to the haemovigilance system in South Africa.
Red cell and plasma product usage remained lower than in the pre-pandemic year of 2019. This was most notably seen in red cell concentrate (RCC) usage that dropped by 13.5% compared to a plasma product usage decrease of 1.5%. The use of platelet products increased by 6.4% in 2021 compared to 2019, and this was due to the concerted effort to overcome a chronic shortage of pooled and single donor platelets.
Continuing the trend from the previous 2 reporting periods, febrile non-haemolytic transfusion reactions and allergic reactions comprised the bulk of the adverse reactions reported, at 35.8% and 20.7% respectively.
Misdirected transfusions accounted for 2.1% of all reported adverse events (2.7/100 000 transfusions) which is an increase from the previous year’s 2.48/100 000 transfusions. This is a worrying observation, given that the rate for 2019 was a much lower 1.4/100 000 transfusions. There is thus a clear need to intensify efforts to address system failures in issuing, handling and administration of blood products, and a collaborative approach will be required.
Notably though, one-fifth (21.1%) of the events were unclassifiable due to incomplete or insufficient information. The reasons for this are multiple and systemic, and include the level of cooperation from treating clinicians, access to and quality of patient records, downstream clinical information from third parties in the case of patient mortality, or incomplete laboratory analysis due to late reporting of adverse events. Once again, a collaborative effort is necessary to address the weaknesses in the system.
Significantly, no transfusion transmissible infections were confirmed. This probably reflects the effectiveness of the infection prevention control (IPC) policies and state-of-the-art testing technology in place across the South African blood service platform, in conjunction with an effective donor-recruitment and donor-screening process.
Donor adverse events showed a downward trend from the previous 2 reporting periods, with a calculated event rate of 37.2/100 000 transfusions (45.8 and 43.8 in 2020 and 2019 respectively). This decrease is likely attributable to the significant decline in collections from scholar donors due to schools being closed during lockdown. The contribution of this donor group to total collections decreased by almost half from 2019.
The 2021 South African Haemovigilance Report presents a mixed bag of successes and concerns, depending on the indicators considered. Overall though, the report paints an encouraging picture of BTS in South Africa.
2021 South African Haemovigilance Report
For more information contact, Dr Caroline Hilton, Lead Medical Consultant (caroline@wcbs.org.za)