A new strain of bird flu has adapted to harbor seals. The H3N8 strain was discovered after 162 seals were found dead on the beaches of New England last September. Five of them were examined post-mortem, and a new study shows that all five died of a flu infection. [readon]
H3N8 has been circulating in birds across North America since 2002. But this is the first known case of the strain adapting to other animals.
This particular virus has the ability to target proteins that are found in human lungs and that could cause the immune system to go into overdrive and attack itself, leading to pneumonia and serious bacterial infections.
Something similar happened with the swine flu outbreak three years ago and which turned out to be more dangerous to young people with strong immune systems than to older people.
“There is a concern that we have a new mammalian-transmissible virus to which humans haven’t been exposed yet,” said Dr. Anne Moscona of Weill Cornell Medical College, who led the investigation. “It’s a combination we haven’t seen in disease before.”
While it’s well-known that pigs are good at mixing up avian and human flu viruses. They can be infected by both at the same time, and the two kinds of virus can combine to produce a hybrid. That’s what happened with the 2009 swine flu. But few scientists have considered the possibility of seals doing the same thing.
“Flu could emerge from anywhere and our readiness has to be much better than we previously realized,” Dr. Moscona said. “It’s important to realize that viruses can emerge through routes that we haven’t considered. We need to be alert to those risks and ready to act on them.”
The new research is published in the journal mBio.