This randomized, controlled, double-blinded phase 2 trial will assess the efficacy and safety of Anti- SARS-CoV-2 convalescent plasma as prophylaxis following exposure to COVID-19 (as defined in the inclusion criteria). Adults 18 years of age and older with high risk exposure as defined by CDC may participate. A total of 500 eligible subjects will be randomized in a 1:1 ratio to receive either high titer anti-SARS-CoV-2 plasma or control (SARS-CoV-2 non-immune plasma).