Gautret et al [58]. Observational study HCQ group: n = 80; no control HCQ, 200 mg/3 times/day for 10 days combined with azithromycin 500 mg on the 1st day, 250 mg/day afterward for 5 days The nasopharynx viral load in most patients received HCQ decreased rapidly. Observation of nasopharynx viral load. Observational study design and no control group; No clinical outcomes were analyzed. Possible confounding factors were not adjusted.