Three mysterious bird flu cases worry experts that another pandemic is looming
This month, two independent cases of bird flu were detected in North American children without any known exposure to infected animals, raising concerns that the H5N1 virus that causes it is inching closer to evolving in a way that allows it to spread between humans. Since April, 55 H5N1 cases have been reported in humans, and all but three have occurred in farmworkers in close contact with dairy cows or poultry, which the virus is infecting in droves. But health officials have not been able to determine the source of three cases in humans, raising questions about whether there is low-level community spread happening. On Nov. 9, government officials in British Columbia reported that a teenager tested positive for H5N1 with no known exposure to an infected animal. Last week, a child in the Bay Area also tested positive for bird flu without any known exposures. These two cases follow a third infection in Missouri reported in September, for which health officials were unable to determine the origins of the infection after an extensive investigation. …