While H7N9 avian influenza caused the deaths of more than 40 people in China earlier in 2013, a new strain of avian influenza has been detected in China, according to a scientific study published August 21 in the journal "Nature." H7N7 has now been discovered in chickens in Chinese poultry markets, the study said.

In experiments, scientists from the University of Hong Kong discovered H7N7 has the ability to infect ferrets, and revealed that this form of avian influenza could transfer to people.

The same study revealed a link between the H7N9 outbreaks and domestic ducks. The virus was believed to have started in wild migratory birds, which infected domestic ducks in China. From there, the ducks spread the virus to chickens in live markets, which was likely how the humans became infected, the study indicated.

The number of humans infected by avian influenza has slowed dramatically since the initial outbreak in March. The Chinese government's closing of many live poultry markets is cited as one reason for the decline in infections.