There have been reported concerns that a measles outbreak could occur at the Super Bowl, but just how serious is the threat?
A recent outbreak of the disease, has Arizona health officials on high alert. There have been seven confirmed cases in the state and officials are monitoring 1,000 people who may have come into contact with those infected.
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Despite the hype, the NFL is assuaging fears, saying that most of the players have been vaccinated. Meanwhile, a local reporter tells ET's Kevin Frazier that most of the cases of measles in Arizona are isolated in the East Valley about 50 miles away from the University of Phoenix Stadium, where the Super Bowl will be played.
Halftime performer Lenny Kravitz wasn't concerned at all when Kevin met up with him in Phoenix.
"I haven't heard a thing about it," the rock star said.
Lenny, who will be joining Katy Perry on the Super Bowl stage, just released a studio album called Strut and is launching the second leg of his world tour in March. He had nothing but good things to say about the pop star.
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"She's really focused," Lenny said. "We've never worked together. I really just met her yesterday and watching her work and how she's running her whole production -- she's got it.
Missy Elliott is also expected to join Katy on stage and the "Roar" singer promised to treat fans to a couple hits.
"What they'll hear that night is going to like a 12 and a half minute sing-along for everyone," Katy told Billboard.