One new human H7N9 case has been confirmed in east China's Jiangsu Province, the provincial health department said on Friday.

The patient. a 75-year-old woman from the provincial capital of Nanjing, is in critical condition, the department said in a statement.

The new case brought the number of infections in the province this year to 8 this year.

H7N9 bird flu has killed 19 in China this year, and the total number of human infections had reached 96 as of Monday, according to the Chinese Center for Disease Control and Prevention.

Li Lanjuan, researcher at the Chinese Academy of Engineering and a specialist in H7N9 prevention, said so far there have not been any cases in which one person transmits the flu to another, and the latter transmits the virus to a third person.

Her team has identified H7N9 virus mutations this year, but the mutations are not large-scale.

"Inter-human transmission is very unlikely," said Li, who added that the virus has not evolved to be extensively drug resistant.

Live poultry trading has been halted in Hangzhou, Ningbo and Jinhua cities in Zhejiang, which reported the largest number of human H7N9 cases.

The National Health and Family Planning Commission said on Wednesday live poultry markets should close if a case of H7N9 avian flu is detected.