Pre COVID-19:From January 1,2016 to December 8,2019; Post COVID-19:From 09 December 2019 to 31 December 2021;2.F1a:Constitutive ratio of positive viruses detected by nucleic acid in respiratory viruses from 1 January 2016 to 31 December 2021;F1b:Comparison of the constitutive ratios of Pre COVID-19 and Post COVID-19 viruses detected;3.(Influenza A viru, InfA), (Influenza A virus H1N1, InfAH1N1), (Seasonal Influenza virus H3N2, InfAH3N2), (Influenza B virus, InfB), (Human Adenovirus, HADV),(Boca virus, Boca), (Human Rhinovirus, HRV), (Human Parainfluenza virus, HPIV),(Human Coronavirus, HCOV),(Human Respiratory Syncytial virus, HRSV), (Human Metapneumovirus, HMPV),(Mycoplasma Pneumoniae, MP),(Chlamydia, Ch). The First quarter: January-March,The Second quarter: April-June,The Third quarter: July-September,The Fourth quarter: October-December.