More cities announced plans to shut down live poultry markets in the face of rising numbers of people infected with the H7N9 strain of bird flu and fears that the Chinese New Year - a peak time for poultry consumption - may worsen the national health threat.

At least 20 people died from the virus - all in coastal areas of Zhejiang province, Guangdong province and Shanghai - in less than four weeks from Jan 1 to 26, according to Xinhua News Agency.

Nationwide, 110 people were infected by Tuesday, according to the China Central Television. Provinces such as Jiangsu, Fujian and Hunan also reported H7N9 cases.