Health officials in China are scrambling to uncover how multiple members of three families in Shanghai and a young boy and girl from neighboring homes in Beijing became infected with a new strain of bird flu. The H7N9 virus, which has killed 17 and sickened at least 82 people since March, is thought to pass from birds to humans. But its spread within families and neighborhoods has flamed fears about possible human-to-human transmission. More than 1,000 close contacts of those infected are under close watch for signs of the disease, according to the World Health Organization.
"We don’t think there’s sustained human-to-human transmission, because the only instances where there might have been human-to-human transmission are between two close family members," said WHO spokesman Gregory Hartl, explaining that the family members and neighboring children may have been exposed to the same infected bird.