Researchers are turning sick days into pay days for some ‘lucky’ volunteers who will be infected with the influenza virus as part of a study on how our bodies combat the seasonal illness. As many as 80 people aged 18 to 50 will get paid $3,300 to inhale a nasal spray containing Influenza A, or the common H1N1 strain, which produces mild to moderate symptoms. They’ll then spend at least a week holed up in a clinic where they’ll be closely monitored with blood samples and nasal and throat swabs to track “initiation, size and duration of various immune system responses and to detect virus shedding,” according to the National Institutes of Health. Symptoms including fever and muscle aches and weakness will be recorded for a total of two weeks, and volunteers will then undergo a 90-day follow-up with a few more blood and nasal samples. The study, which began last week and runs until May, is sponsored by the NIH.