. >> reporter: for "nightline," i'm cecelia vega in los angeles. >>> next project youth, meet the reason dan harris is happier, by one simple life change. >>> and just when you thought you saw it all, one passenger on a bus will really surprise you. if you have moderate to severe rheumatoid arthritis like me and you're talking to your rheumatologist about a biologic... this is humira. this is humira helping to relieve my pain and protect my joints from further damage. this is humira giving me new perspective. doctors have been prescribing humira for ten years. humira works for many adults. it targets and helps to block a specific source of inflammation that contributes to ra symptoms. humira can lower your ability to fight infections, including tuberculosis. serious, sometimes fatal infections and cancers including lymphoma have happened, as have blood, liver, and nervous system problems, serious allergic reactions, and new or worsening heart failure. before treatment get tested for tb. tell your doctor if you've been to areas where certain fungal infections are common, and if you've had