Health care has always been a magnet for campaign scare tactics, from Medicare cuts to the myriad falsehoods about Obamacare. But Sen. Mark Pryor has taken it up a notch: He's thrown the Ebola outbreak into the mix.

Pryor, the Arkansas Democrat who's one of the Senate's most vulnerable incumbents, released a new ad Tuesday criticizing his opponent, Rep. Tom Cotton, for voting to cut funding for pandemic preparedness—and tying the vote to the Ebola outbreak in West Africa.

"Tom Cotton voted against preparing America for pandemics like Ebola," the ad's narrator says, following news clips about the outbreak, which has killed more than 1,400 people in West Africa and zero in the U.S.

The ad cites Cotton's vote against a 2013 bill that required the Health and Human Services Department to develop specific strategies for pandemic preparedness and made it easier to access experimental drugs during emergencies. Cotton was one of 29 House members to oppose the measure.

Pryor's ad is tapping into a real, but largely irrational, fear.

A recent survey found that 40 percent of Americans believe there will be a large Ebola outbreak in the U.S., and roughly 25 percent are worried that an immediate family member will be infected.

An Ebola outbreak in the U.S. is extremely unlikely. The virus has never been detected here; the two aid workers treated for Ebola in Atlanta this summer were flown in from Africa, where they contracted the virus. They appear to have beaten Ebola, and public health officials say America's sophisticated medical system would be able to quickly isolate the virus, preventing a widespread outbreak, if a case does pop up in the U.S.

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