Send SMS to CDC via mobile phone.

Individuals traveling with mobile phones will be fed back to the epidemic prevention and control headquarters in a unified manner. If the mobile phone number has recently entered or stayed in a city or region in a high-risk area of COVID-19, it will automatically send epidemic prevention information to mobile phone users. According to the feedback information, the provincial and municipal epidemic prevention and control headquarters will grasp the specific travel trajectory information of the mobile phone number, and will call the mobile phone users to report to the community or street in time to avoid the spread of the epidemic if it is found that there are cities or regions that have recently entered or stayed in the high-risk areas of COVID-19 epidemic.