China’s National Health and Family Planning Commission (NHFPC) revealed on Monday that infectious diseases killed 1,157 people in January, with H7N9 avian flu accounting for 31 of them.There were 457,766 cases of infectious diseases reported last month around the country except Hong Kong, Macao and Taiwan. No cases of Class-A infectious diseases were reported. Plague and cholera are categorized as Class A, the most serious category, according to (Xinhua) news agency.A total of 272,005 cases of 22 kinds of Class-B infectious diseases were reported, leading to 1,136 deaths, according to the commission.Most Class-B cases involved viral hepatitis, tuberculosis, syphilis, gonorrhea, bacillary and amoebic dysentery, the NHFPC said.Class-C infectious diseases claimed 21 lives in January, with infectious diarrhea, foot-and-mouth disease and influenza reported most frequently.