The pearl epidemic in Cangzhou began on June 23, 2020. According to relevant public information, in the document issued by Cangzhou Mingzhu Epidemic Prevention and Control Office, on June 23rd, 2020, a citizen of Cangzhou developed symptoms due to contact with confirmed cases, and was diagnosed as a pneumonia case infected by novel coronavirus after testing, which was also the first case of COVID-19 in Cangzhou.