This is an observational study designed to learn more about how COVID19 convalescent plasma works in patients with COVID19 compared to those patients who did not receive convalescent plasma treatment. Information about patient recovery will be collected from participants' electronic medical records to evaluate safety, clinical outcomes, and SARS-CoV2 antibody responses in patients who were treated with convalescent plasma under a separate expanded access protocol, NCT04372368.

This a prospective, observational cohort trial to evaluate safety, clinical outcomes, and SARS-CoV2 antibody responses in patients who were treated with anti-SARS-CoV-2 convalescent plasma under Expanded Access protocol, NCT04372368. Hospitalized patients with acute respiratory symptoms with or without confirmed interstitial COVID-19 pneumonia will be enrolled. The investigators anticipate that a minimum of 150 eligible subjects will be enrolled to receive COVID19 convalescent plasma over the 12 month period for the FDA IND expanded access protocol, NCT04372368, to provide COVID19 convalescent serum, which is a separate treatment trial. This observational protocol will co-enroll patients in parallel with the expanded access protocol and expects to enroll approximately the same number of patients but no treatment will be provided as part of this protocol. Additionally, the investigators will use Compass data with identifiers to pull information on hospitalized control COVID19+ patients from hospital admission date 4/20 to current for comparison.

This protocol is limited to data collection using the EMR to evaluate outcomes following COVID19 convalescent plasma treatment. Patient-linked specimens will not be obtained and analyzed outside of the expanded access protocol for distribution of COVID19 convalescent plasma. For this protocol, only de-identified, discarded samples may be obtained during routine patient care. Thus, consent will only be obtained from patients/subjects for participation in data abstraction/analysis from the electronic medical record.

Inclusion Criteria:

• Age 18 years or older
• Hospitalized with COVID-19 respiratory symptoms and confirmation via COVID-19 SARS-CoV-2 RT-PCR testing.
• Patient treated with COVID19 convalescent plasma.
• Patient or surrogate designated decision maker is willing and able to provide written informed consent.

Exclusion Criteria:

• Receipt of pooled immunoglobulin in past 30 days
• Contraindication to transfusion or history of prior reactions to transfusion blood products

Hospitalized patients treated with anti-SARS-CoV-2 convalescent plasma under the Expanded Access protocol NCT04372368. Patients with acute respiratory symptoms with or without confirmed interstitial COVID-19 pneumonia will be enrolled. This observational protocol will co-enroll patients in parallel with the expanded access protocol and expects to enroll approximately the same number of patients but no treatment will be provided as part of this protocol.