The coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).1 The SARS-CoV-2 is a β-coronavirus, which is an enveloped non-segmented positive-sense RNA virus.2 It is spread by human-to-human transmission via droplets or direct contact. Based on the current epidemiological investigation, the incubation period is 1 to 14 days, mostly 3 to 7 days. Among patients with pneumonia caused by SARS-CoV-2, fever was the most common symptom, followed by cough.3 Influenza, commonly called “the flu”, is an infectious disease caused by influenza viruses.4 The symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms typically begin 1-4 days after exposure to the virus and last for about 2-8 days.5 RSV is a respiratory virus that usually causes bronchiolitis (inflammation of the small airways in the lung) and pneumonia (infection of the lungs), especially for infants and older adults. People infected with RSV usually show symptoms within 4 to 6 days after getting infected. Symptoms of RSV infection usually include runny nose，decrease in appetite, coughing, sneezing, fever, wheezing. These symptoms usually appear in stages and not all at once.6