Category B infectious diseases managed under Category A are four, namely, infectious atypical pneumonia, pulmonary anthrax in anthrax, human highly pathogenic avian influenza, and poliomyelitis. These four diseases, although in category B infectious diseases, but need to be managed according to category A infectious diseases, that is, must take the reporting and control measures of category A infectious diseases. There are mandatory requirements for the reporting time of Class A infectious diseases, which are required to be reported through the Infectious Disease Information Network System within two hours after the onset of the disease in cities and towns, and should not exceed six hours in rural areas. The disease is more contagious, and active reporting allows for close monitoring of isolation and testing of patients who have been exposed to infectious diseases, which allows for good control of the occurrence and development of the disease.