Steven Tyler

The Aerosmith frontman and former 'American Idol' judge discovered he had Hepatitis C in 2003.

During an interview with the 'Today' show in 2006, the singer said: "I've had Hepatitis for a long time, asymptomatically. It's one of those things that people don't talk about, but it's treatable.”

After 11 months of treatment and while his band wasn't touring, Tyler was cured of the disease. Since then, he has encouraged people to get screened and treated.