H3N8 is known to have been circulating since 2002 after first emerging in North American waterfowl. It is known to infect horses, dogs and seals, but has not previously been detected in humans
A villager buys chickens at a rural market in Linquan County, Fuyang City, Anhui Province, China, April 27, 2022. The NHC reported a human case of H3N8 avian influenza infection in Henan Province on April 26. (Credit: CFOTO/Future Publishing via Getty Images)