1) Known COVID-19 positive test at baseline (if available) 2) Symptomatic for possible COVID-19 at baseline 3) Known hypersensitivity reaction to hydroxychloroquine, chloroquine or 4-aminoquinolines 4) Known retinal disease 5) Known porphyria 6) Known chronic kidney disease (CKD; eGFR<30ml/min) 7) Known epilepsy 8) Known heart failure or conduction problems 9) Known significant liver disease (Gilbert's syndrome is permitted) 10) Known glucose-6-phosphate dehydrogenase (G6PD) deficiency 11) Currently taking any of the following contraindicated medications: