A China, World Health Organization (WHO) report said the most severe H7N9 bird flu cases occurred in elderly male patients living in urban areas.

The report, which was published on Saturday, said the reason why the group is the most affected is still being researched.

It also said the virus has a higher potential for human-to-human transmission than any other known bird flu virus.

As of May 13, the Chinese mainland had reported 130 cases, with 35 deaths.

Global Times – Xinhua