Patient characteristics and setting  Facility cases: among clinically suspected patients: those with a positive RT‐PCRFacility controls: clinically non‐suspected patients + suspected patients with negative RT‐PCRCountry: ChinaDates: 14 January 2020‐9 February 2020Symptoms and severity: all patients admitted, with exposure history to COVID‐19, so all levels of severity; days from illness onset until admission (median, IQR): 2.0 (1.0‐5.0); patient population with general mild disease and limited presence of comorbidities (range 0%‐2.3% (COPD))Demographics: age: controls median 40.0 years (IQR 32.5‐54.5), cases median 39.0 years (IQR 37.0‐41.5)M%/F%: cases 71.4/28.6, controls 63.2/36.8Exposure history: epidemiological history of exposure to COVID‐19 (as per WHO guidance)