This is Side Door, a podcast from a Smithsonian with support from PRX.

I'm Tony Cohn.

In 1999, literally, the crows started to fall out of the trees dead.

And I remember coming here to USA and going to a conference where they said that this was clearly an act of bioterrorism. That's Y2K if you

remember all the panic around that, Herfield was very worried about a new bug

that appeared out of nowhere in the US.

And imagine, like all of a sudden you're in your garden and the birds are falling from the trees

and you're driving your kids to school and there's like dead birds on the pavement.

I mean this, it super shocking and and it was

actually crows which are kind of creepy anyway, you know.

It's like an Alfred Hitchcock and I was like what is happening here?

Experts in her field really feared this was a bioterrorism attack. They thought,

Somebody had put this virus on the shores of the eastern coast of USA and they were trying to kill the US people.

They looked at the birds more closely.

It turned up that they all shared a virus, but it was an African virus, which was weird.

And we started to look more closely into it and see how this possibly could have got to the shores of USA.

And literally there was a series of freak weather patterns

and this put the birds that would normally migrate

to Northern Europe from Africa.

It flew them over to the east coast of the United States instead.

So West Nile virus is generally a bird virus.

You've probably heard West Nile mentioned before.

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