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2 Epidemiological Characteristics
2.1 Source of Infection
At present, the major source of infection is the patients with COVID-19,and asymptomatic 2019-nCoV carriers seem also a potential source of infection.
2.2 Route of Transmission
COVID-19 is mainly transmitted by droplets and contact. Aerosol transmission is possible when people have prolonged exposure to high concentrations of aerosols in relatively closed spaces.
2.3 Susceptible Inh4iduals
Humans of all ages are generally susceptible.