Asymptomatic cases of coronavirus disease 2019 (COVID-19):A review of
literature on clinical characteristics and implications for epidemic
control
Abstract
At present, the epidemic of Coronavirus Disease 2019 (COVID-19) is
spreading worldwidely. Humans may be compelled to live with the viruses
for a long time. The asymptomatic infections are contagious and the most
difficult to control, easy to cause the accumulation of infection
sources in the community. More and more asymptomatic cases have brought
great challenges to the control of the epidemic. This review provides
relatively comprehensive and updated information about asymptomatic
cases of COVID-19. We find most of asymptomatic carriers are young
people, and there are more asymptomatic infections in children compared
with adult patients. Some asymptomatic carriers especially children have
a longer communicable period than the confirmed cases. There is a risk
of reoccurrence of positive result of nucleic acid test in asymptomatic
cases. The chest CT findings of asymptomatic infections were mainly GGO
, mostly peripheral distribution and restored quickly. Aerosol and
fomite transmission of SARS-CoV-2 by asymptomatic carriers is plausible,
so every person releases potentially infectious aerosols all the time.
All countries in the world should raise public awareness of protection
and strengthen social security measures to prevent second outbreak
caused by the asymptomatic infections.