by Monika Buczek — Tu­ber­cu­lo­sis (TB), is an in­fec­tious dis­ease caused by the bac­terium My­cobac­terium tu­ber­cu­lo­sis (Mtb). Symp­toms of an ac­tive TB in­fec­tion in­clude chronic cough with blood-tinged spu­tum, fever, and weight loss. In fact, prior to the 1882 dis­cov­ery of the mi­crobe by Robert Koch, TB was called "con­sump­tion" be­cause the rapid rate with which in­fected pa­tients lost body mass made them ap­pear to be "con­sumed" by some un­known en­tity.