Sarah King isn't afraid of having the flu — in fact, she considers herself an "excellent sick person."
"I have a pretty high pain tolerance," King says. "I'm not a person that whines a lot. I just kind of suck it up."
So when she heard about a medical study that pays volunteers about $3,000 to be infected with the live flu virus, King thought the offer sounded too good to pass up. Last fall, she checked in for a 10-day stay at Saint Louis University's "Hotel Influenza," a quarantine unit where researchers study how the human immune system fights the flu.