WASHINGTON (CBS DC) — The H7N9 strain of bird flu can spread among ferrets, and under certain conditions, could begin to do the same among humans.
The study included infecting ferrets with the virus in the lab. Ferrets were used as the animal model for human flus because the mammals get the same viruses as humans, and they show symptoms of the infection.
“The emerging human H7N9 influenza is infectious and transmissible in mammals,” reported the study led by researchers at Shantou University, the University of Hong Kong and co-authored by colleagues in the United States and Canada.
“Under appropriate conditions, human-to-human transmission of the H7N9 virus may be possible,” the study added.
So far there have been no known cases of human-to-human spread of the new virus, which has infected 131 people and killed 36 since it first emerged in China in March. According to the World Health Organization, as of May 17, health officials knew of 131 people in China who had fallen ill with the H7N9 virus, including 36 who died. Most of these cases — about 75 percent — were people who had direct contact with poultry.
“The findings suggest that the possibility of this virus evolving further to form the basis of a future pandemic threat cannot be excluded,” the research team, led by bird flu expert and microbiologist Yi Guan, told Reuters.
If the virus were found to be able to spread easily among humans, experts fear it could trigger a widespread pandemic. Animal studies are a first step toward understanding how easily the virus might spread in people.
According to the report, scientists infected lab ferrets with a sample of H7N9 taken from one of the people who died from it, and found that the virus spread among ferrets in direct contact, said the report.
Researchers also tested the virus on pigs, because they are often incubators for influenza viruses, and are considered even closer than ferrets to humans. However, it didn’t pass between them as well as it did in the ferrets.
“If the study has shown that one pig had easily infected another pig, then I would be more concerned,” Anthony Fauci, head of the U.S. National Institute of Allergy and Infectious Diseases, told AFP. “Under very experimental circumstances, one mammal can infect another one by direct contact.”