Risk classification standard: 1, medium risk area, there are two situations: (1) There are more than 50 confirmed cases in COVID-19, and there is no clustering epidemic within 14 days; (2) There were newly confirmed cases within 0/4 days of/kloc, and the cumulative confirmed cases in COVID-19 did not exceed 50;
2. High-risk areas: There were more than 50 cases in COVID-19, and a cluster epidemic occurred every 14 days.
3. Low-risk areas: There are no confirmed cases in COVID-19, or there are no new confirmed cases in 14 days.