Chinese officials expressed confidence in curbing the H7N9 strain of bird flu, citing how the country has built capacity to deal with epidemics since the SARS outbreak.
However, the possibility of the virus being transmitted between humans cannot be ruled out, a World Health Organization official said.
With three more cases reported on Monday, China has recorded 24 human cases of H7N9, seven of them fatal.
The three cases reported on Monday were in Shanghai and Jiangsu province.
A 4-year-old boy in Shanghai who on Thursday was confirmed infected with H7N9 has recovered, showing that not all human infections are critical.
“At this time, there is no evidence of sustained human-to-human transmission of the virus, but no one can predict the future,” O’Leary acknowledged, since influenza viruses can mutate.
Liang Wannian, director of the health emergency response office under the National Health and Family Planning Commission, said, “We are closely monitoring the situation and have expanded virus tracking into more areas in the country.”
Since the SARS epidemic in 2003, China has set up a nationwide surveillance network comprising more than 500 hospitals and 400 labs.
Mandatory reporting of unexplained pneumonia cases by health authorities has helped track the H7N9 virus.
Liang indicated that the virus might spread outside Shanghai and Zhejiang, Jiangsu and Anhui provinces.
But further information about the virus – how it is transmitted, potential animal hosts and how easily it can spread – remains limited, he said.
For other parts of the world, particularly neighboring countries, O’Leary urged H7N9 testing of serious and unexplained influenza cases.
“But so far it’s only in a small number of provinces in China,” he said.
The virus appears to spread mainly from birds to humans in a sporadic way, he said.

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