Dangerous History
The genetic secrets of a savvy killer
By Emily Sohn
Throughout recorded time, tuberculosis has wrought death among the people infected and frustration among those trying to tame it. As recently as the 1950s, prescribed treatment included little more than rest, sunlight, and fresh air. Today, patients take powerful drug cocktails for months. Even so, tuberculosis kills more people each year than any infectious disease other than AIDS.
And it is still unclear exactly how Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB) in people, does its damage. Other mysteries include why only some people get sick after being infected and why some outbreaks have managed so effectively to dodge vaccines and to resist antibiotic treatment.