Is there any epidemic prevention survey or public security survey to investigate the positive trajectory of COVID-19?

Public security department to check. According to the national epidemic prevention regulations, the Municipal Public Security Bureau set up a special class on epidemic prevention and control big data to help the epidemic prevention department find out the source of the epidemic, find out the information of the infection chain and the activity track of relevant personnel in COVID-19, and push the data to the relevant departments at the first time to ensure that "no one is missing", so it is the Public Security Department. "Public security" is called "people's public security", and the police who are generally called "public security" in China refer to the people's police of public security organs, and "public security police" refers to the people's police who safeguard citizens' safety.