Bird Flu: H7N9 strain kills two in China

A strain of bird flu that had previously never infected humans has  been contracted by three people killing two in China.
The two dead are reported as living in Shanghai, China and a third thought to be in a critical condition from  nearby Anhui province.
It is unclear how the strain spread, but the three did not infect each other or any close contacts, officials say.
 There are no known vaccines against the H7N9 virus making it all the more worrying for health officials if this strain of bird flu now possesses the ability to freely pass between humans.
Michael O'Leary, China representative for the World Health Organization (WHO) said: "The question is whether the virus will mutate to become more infectious, human to human. There is no evidence of that at this time but viruses change all the time."
The more common H5N1 strain of avian influenza has killed more than 360 people between 2003 and March 12 this year, according to the WHO.
 The WHO says that most avian flu viruses do not infect humans and the majority of H5N1 cases have been associated with contact with infected poultry.
China is considered one of the most at-risk nations because it has the world's biggest poultry population and many chickens are kept close to humans in rural areas.