The World Health Organization expresses "tremendous concern" over the spread of the H5N1 strain of avian flu to new species, including humans. A case of a person being infected by a dairy cow in the United States sparked fears earlier this month.
The fear is that this virus will adapt to become capable of transmitting from human to human. Currently, there is no evidence of direct transmission between two people, but the WHO calls for further research on this subject. "It remains, I think, a huge concern," Jeremy Farrar, chief scientist at the U.N. health agency, told a news briefing in Geneva. "It's tragic to say, but if I'm infected with H5n1 and I die, it's over. But if I go around the community and transmit it to someone else, then you start the cycle,' he explained, believing that infection surveillance and detection systems "do not are never sufficient.