The impact of COVID-19 on blood supply–demand balance and the association between group donations and economic performance: evidence from Zhejiang, China

Background: The COVID-19 pandemic significantly disrupted the balance between blood supply and demand; however, limited evidence reveals how this imbalance emerged, particularly across specific blood types. Changes in donation patterns during the pandemic and their association with the local economy also remain underexplored. Methods: Using provincial-level data from 2014 to 2023, we used an interrupted time series model to analyze the trends in blood supply, blood demand, and group donations caused by the pandemic. Generalized least squares and distributed lag models were applied to examine the relationship between group donations and local economic performance. Results: The pandemic led to an immediate decline in the supply-to-demand ratio for blood, with types A and O most severely affected. Group donations were positively associated with local economic performance, although COVID-19 attenuated this relationship. Conclusion: Tailored strategies are needed for blood types in high demand. Supporting group donations may help promote economic resilience during public health crises.