| ■ Evolving Bird Flu Viruses May Pose Pandemic Threat | 2008.06.02 |
| U.S. researchers have identified certain strains of bird flu that appear to be moving closer to developing traits that could trigger a human pandemic. They found that a few of the H7 virus strains that caused minor, non-transmissible infections among people in North America between 2002 and 2004 may be evolving the same human tracheal cell sugar-binding properties seen in flu viruses that caused global pandemics in 1918, 1957 and 1968, Agence France-Presse reported. "These findings suggest that the H7 class of viruses are partially adapted to recognize the receptors that are preferred by the human influenza virus," said Terrence Tumpey, a senior microbiologist with the U.S. Centers for Disease Control and Prevention. If these H7 viruses continue this type of evolution, they may be able to pass more easily between animals and people, said the researchers, who called for strict surveillance of avian flu viruses, AFP reported. |