Experts say they have found key component of the H5N1 bird flu virus . It is hoped this will lead to better medication to fight the infection . China reported its first human-to-human infection in 2005 . Comment:
Experts say they have found key component of the H5N1 bird flu virus . It is hoped this will lead to better medication to fight the infection . China reported its first human-to-human infection in 2005 . Since 2003 , the World Health Organization has confirmed 404 human cases .