Chinese virologists have tracked down the source of the latest strain of avian
influenza, which has killed 23 people and infected over 100 so
It turns out that chickens in poultry markets are the source
of the human infections, and in particular, the markets of the
central Eastern coastal province of Zhejiang.
Thirty researchers from around China took samples from human
patients and compared them to chickens from various regions. It
turns out that the virus from the patients was very close to an
epidemiologically-linked market chicken found in the province.
That's only half the picture, though. The H7 portion was traced
to domestic ducks in Zhejiang, whereas the N5 chunk was closer to
viruses found in wild birds in South Korea.
"The evidence ... suggests it is a pure poultry-to-human
transmission and that controlling (infections in people) will
therefore depend on controlling the epidemic in poultry," said
Kwok-Yung Yuen from the University of Hong Kong.
Meanwhile, the World Health Organisation has warned that this
particular strain of bird flu is transmitted more easily than the
notorious H5N1 strain which has been circulating since 2003, making
it "one of the most lethal" flu viruses.
While there is no evidence that the virus is yet able to
transmit from person to person, the scientists warned that "further
adaptation of the virus could lead to infections with less severe
symptoms and more efficient person-to-person transmission."