Dirty JobPhotograph from Reuters



Technicians wearing protective suits begin to kill poultry at Huhuai poultry wholesale market last week in Shanghai, China, where the new H7N9 bird flu virus was first detected in pigeons. Centers for Disease Control and Prevention's influenza division, told ABC News that her agency is working on a vaccine that uses the virus's genetic code rather than the virus itselfa first for the CDC.



"Nobody knows, and at this point nobody can know, because influenza viruses are inherently so unpredictable. They mutate continually. Their eight major gene segments snap apart, like Poppit ugg boots outlet location beads, and reconnect with segments from other flu viruses," he wrote.



Passing the TimePhotograph by Darley Shen, Reuters



Vendors play chess beside birds at a poultry market in Wuhan, Hubei Province, on Sunday. The market closed live poultry trading on Monday amid concerns about bird flu.



Traces of the H7N9 virus have been found in pigeons, chickens, and quail, all available at live markets in Shanghai and other Chinese cities, and officials have ordered mass cullings and market closures, according to Quammen.



"If each ugg australia outlet of the people so far infected caught the virus directly from a bird, as currently supposed, such cullings and market closures might help," he wrote. (Read Quammen's National Geographicpiece "Infectious Animals.")