The main cause of TB is Mycobacterium tuberculosis, a small, aerobic, nonmotile bacillus.[11] The high lipid content of this pathogen accounts for many of its unique clinical characteristics.[21] It divides every 16 to 20 hours, which is an extremely slow rate compared with other bacteria, which usually divide in less than an hour.[22] Mycobacteria have an outer membrane lipid bilayer.[