To determine whether convalescent blood products (CBPs) could offer a survival advantage for patients with severe acute respiratory infections (SARI) of viral etiology..
..According to observational studies, the cases received CPBs showed a decline of all-cause mortality compared with cases without using (OR 0.36, 95% CI 0.23 to 0.56, P < 0.00001). The all-cause mortality in the randomized controlled trials (RCTs) showed no difference between the interventional group and the control group (OR 0.82; 95% CI 0.57 to 1.19; P = 0.30). Besides, CBPs did not increase the risk of adverse events between these two groups (OR 0.88; 95% CI 0.60-1.29; P = 0.51). Using CBPs earlier, compared with using CBPs later, was associated with a significant reduction in all-cause mortality (OR 0.18; 95% CI 0.08-0.40; P < 0.0001).
Based on the outcomes of RCTs, CBPs could not decrease all-cause mortality. Furthermore, comparing with later initiation of convalescent blood product therapy, earlier initiation of convalescent blood product therapy might decrease the rate of mortality.