It seems to make a resurgence whenever there are more human hardships such as overcrowding, poverty, poor sanitation, starvation and war. The indigent population of any city is usually the first people to be affected by such a resurgence. Sometimes the infection may move from the lungs and cause more serious problems elsewhere in the body. A person with active tuberculosis is contagious only when there is active lung infection and detectable MTb in what the person coughs up.
Active tuberculosis can be lethal if untreated.
This is scary stuff. Yes if you think TB is as contagious as Flu and as lethal as Ebola, Hantavirus, Bubonic Plague et cetera . No if you are simply concerned about whether you or those you care about have had significant exposure to someone with active tuberculosis. Significant exposure is having been in close proximity in an indoor setting with the affected individual for more than a few hours or recalling being coughed on by same. All this means is that there is a possibility of later developing active tuberculosis.