A 53-year-old man in Taiwan was confirmed to be infected with the new type of bird flu, China's state-run Xinhua news agency reported quoting a Taiwanese official statement.
The patient is believed to have been infected after he visited SuzhouCity in China's JiangsuProvince which has reported several cases of H7N9.
China has reported 108 H7N9 cases and 22 deaths since the first infections were confirmed on March 31.
The patient said he did not have any contact with birds or eat undercooked poultry or eggs during his stay in Suzhou. He also tested Hepatitis-B-positive and suffers from high blood pressure and his condition was stated to be serious, the statement said.
China has already provided samples of the human H7N9 avian flu strain to Taiwan for joint research.
Meanwhile, WHO's influenza expert Dr Keiji Fukuda, who was part of investigation team that toured affected areas in China said H7N9 is more lethal as it spread easily from birds to humans unlike H5N1, which caused over 350 deaths world wide.
"This is definitely one of the most lethal influenza sviruses we have seen so far," Fukuda told media here.
An WHO statement said all the H7N9 infections identified so far are isolated cases and there is no evidence of any inter-human transmission.
Although several cases of family-clustered infections with H7N9 avian influenza have occurred in China, there is no definitive evidence indicating that the virus was transmitted from the same source or among different people, according to a China-WHO joint statement.
Moreover, there has been no sustained human-to-human spread monitored so far, it said, adding that the possibility of such situation cannot be ruled out, as scientists are not sure whether the virus will develop to be inter-human communicable.
Severe symptoms have been observed in most of the infection cases, but uncertainty remains over how many people may be carrying the virus without showing any symptoms, the statement said.
"That is why we are carefully working on the virus and closely monitoring its spread," it explained.
Also Liang Wannian, a top official with China's National Health and Family Planning Commission, warned that the disease may further spread.
The authorities will intensify the monitoring of infections among animals and people, he said.
Image: An airport staff member takes a passenger's temperature at Taoyuan International Airport in Taiwan on Wednesday.
Photograph: Reuters
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