A feasibility intervention study of convalescent plasma for MERS-CoV infection treatment failed to identify sufficient high-titer plasma from patients with confirmed/suspected MERS, their close family members, or healthcare workers exposed to MERS (n = 12 reactive ELISA/443 serum tested). Two fresh-frozen plasma units (250–350 mL/unit) would be required for each enrolled MERS patient (NCT02190799). Encouragingly, anti-MERS CoV titers measured by ELISA correlated with microneutralization (MN) assays [6].