Yeah, and a positive TB test for what appears to be a healthy person isn't really a big deal. You'll take some medication for a period of time, they retest and you should come back clean. What happens (to most healthy people) is that your body "walls off" the TB in a small spot in your lungs. The TB stays dormant, pretty much beaten down and nonthreatening but still very much alive. If something happens and you become immuno-suppressed (HIV, major illness/surgery) the TB can "break out" of it's "jail cell" and cause full blown TB (never fun). I'm making this far more simple than it really is, but finding out your status and getting cleared up could REALLY benefit you down the road.