PORTLAND, Maine — A new strain of avian flu that jumped to the seal population caused the deaths of more than 100 harbor seals along the New England coast last fall, a study found. So far, there is no indication that humans are capable of contracting the new virus strain, but scientists plan further study of its implications.
‘‘Any time we find a new virus, there’s a concern that it’s going to have a larger impact than on the population in which we originally find it,’’ said W. Ian Lipkin, one of the authors of the study and a professor of epidemiology at the Mailman School of Public Health at Columbia University.
All told, 162 dead seals were found between September and December from southern Maine to Massachusetts. The seals, most 6 months old or younger, attracted attention when the first were found off New Hampshire because they were otherwise healthy. The report, released this week, identifies cause of death as a new strain of influenza A, called H3N8, capable of jumping from birds to marine mammals.
Other strains of H3N8 have been found in dogs and horses, but this strain had many new mutations that make it different, Lipkin said. The report said that further study is necessary and that the emergence of the strain ‘‘must be considered a significant threat to both wildlife and public health.’’
The flu strain is enough of a concern that scientists advised surfers, beachgoers, and others not to approach sick seals or other marine mammals. Marine scientists are taking infectious disease precautions, Lipkin said.
‘‘I don’t think people should approach sea life that appears to be ill, whether we’re talking about seals or whales or any other mammals,’’ he said.
The report was compiled by scientists at the Center for Infection and Immunity at Columbia University’s Mailman School of Public Health; the National Oceanic and Atmospheric Administration; New England Aquarium; the US Geological Survey National Wildlife Health Center; SeaWorld; and the EcoHealth Alliance.