An emerging strain of influenza that’s killed seals off the New England coast may pose a future threat to humans and other wildlife, warns a new report.

The report, published on July 31 in the journal mBio, said the H3N8 virus caused a fatal outbreak of pneumonia in 162 New England harbour seals from September to December 2011.

The researchers believe the virus may have evolved from a strain that is currently found in birds.

What’s particularly concerning is that the virus naturally acquired mutations that are known to boost its transmission and intensity in mammals. And it’s this “jumping” from mammal to mammal that’s causing scientists to worry it could one day infect humans, according to the report.

"There is a concern that we have a new mammalian-transmissible virus to which humans haven't been exposed yet. It's a combination we haven't seen in disease before," the report’s editor Dr. Anne Moscona, professor of pediatrics and of microbiology and immunology at New York’s Weill Cornell Medical College, said in a news release.

Researchers believe the H3N8 virus may be the first recorded account of a new group of flu viruses that have the potential to persist and move between species.

Dr. Earl Brown, director of the Emerging Pathogens Research Centre in Ottawa, told CTV News Channel Tuesday that scientists are “always nervous” when they see a virus switching from mammal to mammal.

“The virus is always in water fowl, so when you see it move into another mammal, it makes you ask: ‘Well, what’s going on here? And can this thing change enough to get into people?’” he said.

Brown said the virus may have passed onto the seals through bird droppings that land on the seals’ eyes and noses.

The fear is that once the virus has acclimatized to the seal, it could then pass to another mammal, he said.

However, if the H3N8 strain starts to infect people, there is an H3 vaccine that could help prevent the spread of the flu, said Brown.

“It wouldn’t be that we’d be totally flatfooted; we may have some past antibodies that would help us in our past vaccines,” he said. “We may be able to get up to vaccine status pretty quick if it came.”

The authors of the study say it is crucial to continue to monitor the virus to better predict how new strains of influenza may emerge in the future, as well as to prevent future pandemics.