Convalescent Plasma for COVID-19 Research (CONCOR-Donor) study, is a national, natural history study of plasma donors recovered from COVID-19. CONCOR-Donor study will address immune response, duration of protective immunity, and clinical factors and host genetics contributing to the variability of immune response. We will also study long-term outcomes from COVID-19 infection. Results from the study will help define therapeutic strategies for COVID-19.

The outbreak caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) led to the global pandemic. There are currently no proven treatments for coronavirus disease (COVID-19), however, convalescent plasma has emerged as a potential therapeutic to prevent clinical deterioration. Convalescent plasma was successfully used for other infections, in small numbers, but there is limited evidence for the efficacy of administering specific, neutralizing antibodies by transfusion of convalescent plasma. The unknown role for convalescent plasma in treating COVID-19 necessitates further study.

As trials are underway to determine efficacy of using convalescent plasma, we will use this unique opportunity to conduct a national longitudinal cohort study of 1000 persons recovered from COVID-19 and volunteer to donate convalescent plasma. Our aims are to:1) determine if the variability of titers of viral neutralizing antibody and ELISA antibody are associated with clinical and demographic factors; 2) determine duration of protective immunity in recovered persons over 1 year and if modified by clinical and demographic factors; 3) determine genetic risk predictors of the antibody response, and 4) create a biorepository available to researchers from across Canada. Based on the World Health Organization (WHO) Coordinated Global Research Map, this project addresses the priority of the natural history of COVID-19 and clinical characterization of antibody response in the convalescent phase and beyond.

Inclusion Criteria:

• Recovered from COVID-19 infection
• Have a positive PCR or serology or a positive household contact
• Signed informed consent form
• Provide blood sample
• Ability to complete a questionnaire

Exclusion Criteria:

• None

All that recovered from COVID-19 above age 17, that have tested positive or a household contact that tested positive regardless of eligibility to donate plasma for the trials.