John Timmer, Ars Technica:
"The 2009 flu pandemic, although not especially deadly, revealed just how quickly a new influenza virus could elude surveillance and spread internationally. It also left health experts eying the disease that many fear could cause the next pandemic: H5N1, the avian flu. According to World Health Organization standards, that virus is phenomenally deadly, killing about half the people that contract it. So far, however, almost all the known cases came from people who were in direct contact with poultry; the flu doesn't seem to spread among mammals."