Human-to-human transmission of the H7N9 bird flu virus might occur on a limited scale in China, the World Health Organization representative to the country said on Monday.

But there is no evidence that the virus will become sustained or widespread among humans, Bernhard Schwartlander said.

China has reported more than 200 human cases of H7N9 since March, the latest ones including a doctor in Shanghai who died from the infection at the weekend, according to statistics released on Monday by the National Health and Family Planning Commission.