In a report on a mysterious virus causing paralysis in children that aired on “CBS This Morning” earlier this week, Dr. David Agus, a medical contributor for CBS News and a University of Southern California medical professor, discussed a so-called enterovirus that is believed to behind paralysis and muscle weakness in nine Colorado children.

The virus, known as Enterovirus D68, had spread throughout the country. Agus urged parents that suspect their child may be infected with this virus to keep their children home from school. However, “CBS This Morning” co-anchor Charlie Rose asked how that particular virus, in addition to the Ebola virus, have been able to spread in recent weeks.

“Well, the world is flat,” Agus explained. “Right now, anybody can get on a plane and end up anywhere in this country and spread these viruses. And we have to be aware of it. We don’t know exactly why there was a dramatic spread this year. But something is happening now. We have multiple viruses. And together with global climate change, things are changing in the virus world and we have to pay attention.”

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