Imaging Immune Activation in COVID-19

Inclusion Criteria:

* Age \>18 years
* Ability to read and understand written informed consent document
* Have a recent diagnosis of SARS-CoV-2 infection as defined by a prior positive SARS-CoV-2 nucleic acid-based diagnostic test performed in a clinical laboratory on one or more nasopharyngeal or respiratory secretion samples.
* \> 14 days since onset of COVID-19 symptoms (or if no symptoms, from time of initial nucleic acid based diagnostic test).
* Laboratory evaluations obtained within 60 days prior to entry.

  * Platelet count ≥75,000/mm3
  * ANC \>1000/mm3
  * Aspartate aminotransferase (AST) \<3 x ULN
  * Alanine aminotransferase (ALT) \<3 x ULN
  * Calculated creatinine clearance (CrCl) ≥60 mL/min as estimated by the Cockcroft-
  * Gault equation

Exclusion Criteria:

* Any medical condition that would compromise the imaging acquisition, in the opinion of the investigator
* Participants who are pregnant (female participants of childbearing age will be tested prior to injection of imaging agent at entry visit/initial visit - positive test will exclude from further participation in the study)
* Participants who are breastfeeding
* Female participants of reproductive potential (defined as women who have not been post-menopausal for at least 24 consecutive months (i.e., who have had menses within the preceding 24 months), or women who have not undergone surgical sterilization, specifically hysterectomy and/or bilateral oophorectomy or bilateral salpingectomy) must have a negative urine or serum pregnancy test with a sensitivity of at least 25 mIU/mL performed within 24 hours prior to PET imaging. Females of reproductive potential will need to be on 2 forms of birth control (excluding withdrawal or timing methods).
* Participants who have had prior allogeneic stem cell or solid organ transplant.
* Screening absolute neutrophil count \<1,000 cells/mm3, platelet count \<75,000 cells/mm3, hemoglobin \< 8 mg/dL, estimated creatinine clearance \<60 mL/minute, aspartate aminotransferase \>3 x ULN, alanine aminotransferase \>3 x ULN.
* Known SARS-CoV-2 shedding within 5 days of PET imaging.
* Previously diagnosed myelodysplasia syndrome or history of lymphoproliferative disease prior to study entry
* Active systemic autoimmune diseases not related to COVID-19.
* COVID-19 vaccine prior to the first PET imaging session. Participants may receive COVID-19 vaccination after the first PET imaging session and the optional second PET scan, with the scan being performed at least 2 weeks following the most recent vaccine dose.
* Prior PET scan or therapeutic radiation within 1 year of study enrollment.