analysis of the genes of these viruses suggested that although they have evolved from avian viruses...

No vaccine currently available for human infection with H7N9: WHO
Excerpt:
4/5/13
 To date, China has confirmed 14 H7N9 cases and five have died.

More than 400 close contacts of the confirmed cases are being closely monitored. Thus far, none of them have developed any symptoms of illness, according to the WHO. "At this time there is no evidence of ongoing human-to-human transmission," it said.

The WHO said it was yet to know the reason for the virus to infect humans. However, analysis of the genes of these viruses suggested that although they have evolved from avian viruses, they showed signs of adaption to growth in mammalian species.

These adaptations included an ability to bind to mammalian cells, and to grow at temperatures close to the normal body temperature of mammals, which is lower than that of birds, it said.

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