The Coronavirus Disease 2019 (COVID-19) pandemic is a highly contagious disease caused by anovel, enveloped single-stranded ribonucleic acid virus named as severe acute respiratorysyndrome coronavirus 2 (SARS-CoV-2). Globally, it affected more than 200 countries with nearly5 million confirmed cases and 0.3 million deaths as of 2020, 22 May.1 The median incubation period of the virus is about 3–9 days, with a range between 0 and24 days.2 The mean serial interval is about 3–8 days, presenting sooner than the end ofincubation. This suggests that one becomes contagious before symptoms present (about 2.5 daysearlier from the start of symptoms). About 44% of transmission is estimated to occur beforesymptoms arise.3
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