The real reason polio is so dangerous

In 1952, polio was everywhere: killing or paralyzing roughly half a million people annually. Yet just 10 years later, paralytic polio cases in the US dropped by 96% and we were on track to get rid of polio for good. But in recent years, the virus started striking back. So, what’s behind these recent spikes? Explore the dangers of poliovirus and the possibility of eradicating this deadly disease.

[TED Ed]