BEIJING, Feb. 10 (Xinhua) -- Virus analysis of the bird flu-infected patients in the Chinese mainland showed no mutation that could cause human to human infection, said Mao Qun'an, spokesman of the Ministry of Health, on Tuesday.
Mao said that eight people were found to have contracted H5N1 this year and five of them died. Scientists had found little mutation in the virus strains separated from those patients, and no mutation that would allow human to human transmission.
He said that most patients had direct contacts with live poultry or even worked at poultry markets.
Since the World Health Organization (WHO) detected the lethal virus, 406 human cases from 15 countries have been reported, according to Mao.
Mao urged health departments and hospitals across the country to be alert to the virus, since most of human infection cases took place in the first quarter of the year.