and it will cut down on all -- by the way, to add to david's point, the treatments now are really working. we have interferon we use, ribovirin and a proet yais inhibitor that is very effective. >> so i ask my daughter i want a hepatitis c test? >> i was just about to say eric is going to ask that question. >> what about the strains, dr. samadi? >> it's not part of your normal test. there's no vaccination for hepatitis c. as doctors and surgeons we're all immune. we get vaccination. a did s. different. that's from contamination of food and water you that want to make sure you protect yourself. but hepc is more common than hiv fourfold and it doesn't get as much publicity. i'm glad they came up with this screeni screening. >> you could have it and not know it. >> so ask for that test. great, docs. >> thank you. >> have you heard about teens and severe concussions? we do hear a lot about that,