摘要
After the outbreak of coronavirus disease 2019(COVID-19),different measures have been taken to control the spread of the epidemic.Most international organizations,countries/regions have issued epidemic prevention guidelines or administrative guidelines,in which citizens are advised to pay attention to personal hygiene(such as washing hands frequently,covering the nose and mouth when sneezing),maintain social distance,and avoid gathering activities,and so on.[1]However,it is noted that instructions on whether citizens need to wear masks and when to wear masks are inconsistent across various countries.
