Effect of Convalescent Plasma Therapy on Mortality and Viral Load in Severely Ill Patients with COVID-19.

The use of convalescent plasma (CP) appeared to be a promising, easily available and safe way of treatment of severe COVID-19 at the onset of the pandemic in early 2020. Conducted in 2020 and 2021, our study of 52 severely to critically ill COVID-19 patients who received CP plasma as a treatment and of 97 controls found no difference in 30-day or 90-day mortality rates. A significant viral load drop in most patients (4.7 log10 [p<0.001] copies/ml) was observed following CP administration. Retrospective analysis of selected inflammatory markers and immunoglobulins showed higher C-reactive protein levels among the study group, and their decrease on Day 7.