Can be detected, first of all, based on cell phone mobile data to determine the location information, also known as the base source positioning method, which is the most commonly used method, but also the new hair in the big data screening, the most efficient means. Secondly, it is analyzed by social interaction information, which does not mean judging by social software information, but combining the existing data, through telephone surveys, mapping visits and other ways, and finally form relatively reliable data information. It can be confirmed by item information, in addition to the screening of passers-by, close contacts, but also lined up a number of items and goods, in the process, through the path of specific virus-carrying items and contact tracing.