What's Surprising and Scary About Avian Influenza Right Now?

One World, One Health

Bird flu – aka avian influenza – is doing what it does best yet again – surprising scientists, public health officials, farmers, and wildlife experts. It’s been spreading among dairy cattle in the United States, something that startles even long-term observers of the virus.

The H5N1 strain of avian influenza was first noticed in the late 1990s and it immediately worried experts, who saw its potential to cause a pandemic. It infects many wild birds without causing them too much trouble, but they can spread it to domestic poultry, which often die en masse. It has occasionally spread to people – just under 900 since 2003 – according to the World Health Organization. But it’s deadly when it does, killing half of these people.

It's a perfect One Health issue – a disease that circulates among animals, spreads from one species to another, and then makes the jump to people. Farming practices, climate change, and the environment all play a role. Now it’s shown up in Antarctica, and at least one person on a dairy farm has been infected.

That surprised Dr. Richard Webby, Director of the World Health Organization Collaborating Centre for Studies on the Ecology of Influenza in Animals and Birds at St. Jude Children’s Research Hospital in Memphis, Tennessee. He says H5N1, like so many flu viruses, is constantly changing and evolving. That’s why it’s so important to keep an eye on it. “If there is one virus I don’t want to catch, this is it,” he says.

Listen as Dr. Webby tells One World, One Health about what experts are working to find out about H5N1’s latest moves.