Methods for detecting an infection with Mycobacterium tuberculosis (Mtb) in a subject are disclosed. The methods include detecting the presence of CD8+ T cells that specifically recognize an Mtb polypeptide. The methods include in vitro assays for detecting the presence of CD8+ T cells in a biological sample, and in vivo assays that detect a delayed type hypersensitivity reaction. The methods can also include detecting Mtb polypeptides and polynucleotides. Reagents for the detection of an Mtb infection are also disclosed.