Evolving bird flu could close markets

摘要

There's good news and bad news. At last report, there have been no new human cases of H7N9 bird flu in China since 8 May. On the other hand, it seems the virus already has many of the mutations that would allow it to spread easily among us while remaining deadly. Meanwhile, New Scien tist can reveal that China is considering closing live poultry markets permanently in an attempt to stop the spread of the virus. H7N9 flu has caused 131 known cases in humans, 36 of whom have so far died, since it emerged in February this year. Tests show that while the virus is a very rare infection of birds in live poultry markets, it is circulating and evolving. But the infection is so rare that those birds can't be passing the virus to enough other birds to keep it circulating. This means it must also be carried, less rarely, by another animal - so far unknown.