In 2020, COVID-19 spread rapidly across the globe, disrupting nearly every aspect of public life, with the healthcare system bearing the greatest burden (1). Among the affected sectors, blood donation and transfusion services were the most affected, as they are highly sensitive to fluctuations in supply and demand. Zhejiang province, one of the most developed regions in China, responded quickly by implementing effective strategies to minimize infection rates and alleviate pressure on the local healthcare system (2). Working in partnership with local businesses, the provincial government introduced innovative tools, such as the health code system, to help with individual health management, including tracking epidemic history, and to prevent further outbreaks (2, 3). Although the pandemic was eventually contained within a relatively short period in Zhejiang, it inevitably changed individual behaviors—individuals initially delayed seeking healthcare, leading to a subsequent surge in demand for medical needs as they attempted to address previously postponed needs (4).

Meanwhile, the pandemic also caused broad consequences beyond its immediate health impacts (5). Movement restrictions and reduced mobility disrupted individuals’ regular access to blood donation centers. Blood centers also introduced additional donor screening and deferral criteria to protect donors and safeguard the blood supply, which further decreased the number of eligible donors (6). Together, these disruptions may lead to short-term declines in blood collections and, in turn, increase the risk of supply shortages and creating downstream challenges for hospitals and patients reliant on transfusions. This public health crisis, therefore, exposed the inherent vulnerability of the blood supply chain, revealing how quickly external shocks may destabilize a system that depends on continuous donor participation. The severity of disruption varied by blood type, with blood type O disproportionately affected the most due to higher clinical demand (7). An adequate blood supply ensures that patients receive timely transfusions, which helps prevent treatment delays and reduces time away from work. Previous studies also show that a well-functioning blood supply–demand system not only helps prevent medical complications but also reduces long-term healthcare costs, thereby supporting both individual well-being and the overall performance of the healthcare system (8).

In China, the blood donation system primarily comes through two channels: individual donations and group donations (9). Individual donations typically involve people who spontaneously visit blood donation sites, often motivated by personal initiative or public appeals. By contrast, group donations are usually organized by community organizations, schools, or workplaces, with blood drives scheduled at specific times (10). To facilitate group donations, blood centers often provide on-site collection services, although this generally requires mobilizing a minimum number of donors to be cost-effective (11). This approach is convenient and efficient for maintaining a stable blood supply. As a complement to individual donations, group donations embody collective action and social solidarity, particularly in the Chinese context, where community-oriented initiatives have strong cultural and institutional support.

During the COVID-19 pandemic, the blood collection-to-supply process could be disrupted through multiple channels. In general, lockdowns and reduced mobility decreased donor attendance and disrupted blood collection. In addition, blood centers implemented additional donor screening and deferral criteria to protect donors and maintain the safety of the blood supply, which could further reduce the number of eligible donors. Together, these disruptions may lead to short-term declines in collections and, in turn, reduce the stability of the blood supply. In addition to affecting blood donations, COVID-19 also has negative impacts on the economy (12). This disruption manifested in severe shocks to the retail, service, and manufacturing industries caused by lockdowns (13). These economic disturbances are intertwined with challenges within the health system, as resource shortages—including those in the blood supply chain—undermined labor productivity and further exacerbated the economic recession. Given this dual burden on both the economy and health system, understanding the correlations between COVID-19, the blood system, and economic performance becomes particularly important. Previous studies have explored the impact of COVID-19 on either blood supply or demand (14, 15), but very few have investigated both aspects simultaneously. Additionally, these studies have not considered its impact on group donations. At the same time, although the correlation between economic development and human health has been widely studied, little is known about the specific role of group donations in supporting economic resilience—especially in the context of COVID-19, when the individual donation channel was severely disrupted. Addressing these gaps is important for both public health and policy planning. From a healthcare perspective, understanding variations in supply and demand by blood type can inform targeted strategies to secure vulnerable blood groups. From an economic perspective, clarifying how group donations contribute to economic performance provides valuable evidence for mobilizing community-based initiatives in future crises. Using provincial-level data from Zhejiang, this study primarily aimed to answer two key questions:

How did COVID-19 affect the balance between blood supply and demand in Zhejiang province, both overall and by blood type?

The COVID-19 pandemic exposed significant vulnerabilities in blood supply chains (20, 21). Our analysis also revealed a notable decline in the overall supply-to-demand ratio during the pandemic, with blood types A and O being particularly affected. While previous studies attributed blood supply challenges during the pandemic to lockdowns and movement restrictions (22), our study did not find a significant decline in blood supply. Instead, the sharp increase in demand for type A and type O indicated that targeted strategies should be developed for specific blood types. The decline in blood demand for type AB after the COVID-19 outbreak may reflect pandemic-related changes in healthcare utilization and hospital case mix, particularly during the early outbreak period. One possible explanation is that the type AB group had been disproportionately affected during the onset of the pandemic. Some studies have reported that group AB was positively associated with a higher mortality risk compared to the other blood types (23, 24). In addition, hospitals implemented patient blood management strategies during periods of constrained supply, which reduced transfusion utilization (25). Since AB recipients represent a relatively small share of the population, AB demand is more sensitive to short-term fluctuations and may show larger relative declines in aggregated time-series data. Blood type O had high demand during the pandemic due to its unique universal compatibility with transfusions. When supply fails to meet its elevated demand, it can place additional strain on healthcare systems. Blood type A was also heavily impacted. One possible reason is that, although type A is relatively common, it is less prevalent than type O in the local population (26), which might limit the available donor pool compared with the most prevalent blood type. Additionally, previous studies identified blood type A as a potential risk factor for COVID-19 infection (27, 28). Individuals with blood type A face a higher risk of contracting COVID-19, which could indirectly affect blood availability during outbreak periods. For example, illness or quarantine could have reduced participation among type A donors. This might further increase the clinical need for transfusions (27). Given the relatively stable blood types B and AB, it is important to implement tailored strategies to protect the supply of blood types that are more vulnerable during public health crises.

We did not find a long-term negative impact on the blood supply-to-demand ratio, which could be attributed to proactive measures implemented by blood centers, including extending the operating hours for donation sites and deploying mobile blood donation vehicles to improve accessibility for donors (29). Meanwhile, local organizations and communities coordinated group donations to meet the high demands for specific blood types (30). We found the pattern of blood donations shifted under the pandemic, with group donations taking up a greater proportion of the total blood collections, which serves as an alternative to traditional individual voluntary donations (31). Before the pandemic, individual donations made up a significant share of total blood collections. The pandemic somehow accelerated the transition to group donations. Local governments and private companies worked closely with blood centers to organize blood drives. Group donation offers the advantage of allowing collections to be scheduled in advance and enabling an efficient collection of larger blood volumes within a limited period (9, 11). This collaborative effort offsets the decline in individual voluntary donations, playing a crucial role in sustaining healthcare resources during the crisis. Other than that, the local government implemented demand-management measures, including promoting autologous transfusions, postponing elective surgeries, and adopting restrictive transfusion strategies with low hemoglobin thresholds. Collectively, these measures reduced non-essential blood use, helped preserve blood inventories, and maintained blood availability for emergency clinical needs (32).

Our analysis found that higher blood demand was negatively correlated with local economic performance. This is not surprising: even when blood supply remains within a normal range, once demand exceeds supply, the balance is broken, and shortages emerge, leading to adverse downstream influences. These imbalances disrupt timely medical care, prolong recovery times, and increase absenteeism, all of which negatively impact economic output. In contrast, the results revealed that an increase in group donations was positively associated with improvements in GRP per capita. Adequate blood donations were found to help reduce the number of individuals on sick leave (33). While this association did not establish causality due to insignificant lag variables, it nonetheless reflects the potential benefits of strengthening the healthcare system through timely blood transfusions. Since it ensures patients receive appropriate clinical treatment, thereby aiding their recovery and reducing workforce disruptions, this ultimately improves individuals’ work productivity (33). Furthermore, group donations facilitated the rapid collection of blood types in shortage, enabling an effective response to clinical needs (34). Community mobilization and collective efforts served as effective avenues for group donations in crisis management, helping to reduce blood shortages and ensure sufficient collection, further contributing to economic resilience during a public crisis. Importantly, our results do not imply group donation should replace individual donation in routine settings; rather, it complements individual donation and may be particularly valuable during emergency situations. Although the interaction term between COVID-19 and group donations was significantly negative—likely due to travel restrictions and logistical challenges faced by blood centers (35)—maintaining or expanding group donations can still be beneficial, since it helps buffer external shocks to the blood supply chain.

Our study focuses on Zhejiang Province, and therefore, the estimated results should be interpreted as province-specific. However, we believe that the main mechanisms identified in our analysis are likely relevant to broader policy planning. First, the ABO distribution in Zhejiang is broadly comparable to the national level, with type O, type A, and type B being the most prevalent blood types (26). This implies that supply–demand imbalances for common blood types are policy relevant beyond Zhejiang. Second, our findings highlight the role of group donation as a complementary channel to individual donations, especially during a public health crisis. We also notice existing regional heterogeneity referring to blood demand and supply in both ordinary and pandemic periods. Before COVID-19, blood supply and demand differed across regions due to variations in population structure, i.e., social and cultural ideas affecting donation willingness, and differences in blood collection infrastructure and management capacity (36, 37). Demand can also vary because of differences in ABO distributions, local healthcare service capacity, i.e., areas with more intensive hospital services may have higher clinical needs, and broader socioeconomic conditions (38). During COVID-19, heterogeneity likely increased further because lockdown stringency and duration differed across regions, donation opportunities, and logistics challenges (39, 40). While our results are context-specific, they provide policy-relevant evidence that can serve as a useful reference for other provinces and for settings with similar blood collection systems.

Our study is not without limitations. First, in our DLM model, it is important to recognize the insignificance of lagged variables when making causal inferences regarding the effect of group donations on economic performance, where the positive coefficient for group donations only indicated a positive correlation between these two variables. Second, our GRP per capita data were available only at a quarterly level, which limited our ability to capture more granular fluctuations that may occur at higher frequencies. This lower resolution may have smoothed over important variations in economic performance that could have been detected with more frequent data. Third, our outcome of interest may be influenced by other variables correlated with either blood supply, demand, or group donations, especially factors such as socioeconomic status or other public health policies. Due to data limitations, our results might either overestimate or underestimate the true effects, thereby affecting the generalizability of our findings. Fourth, we applied first-order differencing to our variables of interest, and this restricted us to predict a long-term consequence as it focuses on short-term changes after differencing.

COVID-19 significantly disrupted the balance between blood supply and demand, particularly affecting blood types A and O the most. However, these imbalances gradually recovered over time, demonstrating the resilience of the blood supply chain through proactive strategies. Furthermore, our study highlighted the positive effect of group donations on the local economic performance. The findings underscore the important role that group donations play in blood collection and the effectiveness of proactive strategies—collective community initiatives and mobilization—in mitigating the adverse effects of public health crises on the healthcare system and economy.