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.
Eight people have already died and 20 others have been infected with H7N9, all of them in eastern China, according to ABC News.
Nancy Cox, head of the U.S. 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 itself—a first for the CDC.
But it's unknown whether the new strain will become a deadly pandemic, writes David Quammen, author of Spillover: Animal Infections and the Next Human Pandemic, in an opinion piece.
"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 beads, and reconnect with segments from other flu viruses," he wrote.