Inclusion Criteria:

• * Household contact of index case: currently residing in the same household as an individual evaluated at NYP via outpatient, emergency department (ED), or inpatient services who (1) test positive for COVID-19, or (2) are defined as suspected cases, or persons under investigations (PUI), by the treating physician.
• * Willing to take study drug as directed for 5 days.

Exclusion Criteria:

• * Age \<18 years old
• * Suspected or confirmed current COVID-19, defined as: (1) temperature \> 38 Celsius; (2) cough; (3) shortness of breath; (4) sore throat; or, if available (not required), (5) positive confirmatory testing for COVID-19
• * Suspected or confirmed convalescent COVID-19, defined as any of the above symptoms within the prior 4 weeks.
• * Inability to take medications orally
• * Inability to provide written consent
• * Known sensitivity/allergy to hydroxychloroquine
• * Current use of hydroxychloroquine for another indication
• * Pregnancy
• * Prior diagnosis of retinopathy
• * Prior diagnosis of glucose-6-phosphate dehydrogenase (G6PD) deficiency
• * Major comorbidities increasing risk of study drug including: i. Hematologic malignancy, ii. Advanced (stage 4-5) chronic kidney disease or dialysis therapy, iii. Known history of ventricular arrhythmias, iv. Current use of drugs that prolong the QT interval