SARS-CoV-2 Serology and Virology Trends in Donors and Recipients of Convalescent Plasma

SARS-CoV-2 has infected millions worldwide. Convalescent plasma may offer a treatment option. We evaluated trends of IgM/IgG antibodies/plasma viral load in donors and recipients of convalescent plasma. 114/139 (82%) donors had positive IgG antibodies. 46/114 donors tested positive a second time by NP swab. Among those retested, the median IgG declined (p<0.01) between tests. Some donors with confirmed SARS-CoV-2 were negative for IgG antibodies. In donors retested there was a significant decline in IgG levels over time. Plasma viral load obtained on 35/39 plasma recipients showed 22 (62.9%) had non-detectable levels on average 14.5 days from positive test versus 6.2 days in those with detectable levels (p<0.01). IgG was higher in those with non-detectable viral loads. There was no relationship between viral load and blood type (p=0.87) or death (0.80). Recipients with detectable viral load had lower IgG levels; there was no relationship between viral load, blood type or death.