Eternal Vigilance Fingers the Flu

The influenza virus is hiding and changing in animal populations. Virologist Ab Osterhaus explains how that could make it more lethal and how we have to keep a constant eye on its development. Katherine Harmon reports

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Flu season is just around the corner in the northern hemisphere. But for birds and pigs, it's flu season year round. These animals are common hosts for the influenza virus, which comes in a wide range of strengths and types—some of which can infect humans. So keeping tabs on the illness in animals is a big focus of flu research.

"We are keeping birds and pigs in numbers that are unprecedented, so you create new niches for animals, and especially for viruses to emerge." Ab Osterhaus, a virologist at the Erasmus Medical Center in Rotterdam, at the recent European Working Group on Influenza conference.

"If these animals are in contact with wild birds, for instance, you create new pathways that didn't exist there in the past."

To find out how viruses from animals might become even more deadly in people, researchers are on the alert.

"Just a couple of mutations in birds suffice to actually make a virus hotter, and so make a virus transmissible from human to human. So I think surveillance for these kinds of things should be increased. We have to do much more.”

—Katherine Harmon

[The above text is a transcript of this podcast.]

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