The bacterium behind TB. Active disease differs from latent infection. Explore its illustrative 3D model, human context, and sources.
M. tuberculosis is a slow-growing bacterium that causes tuberculosis (TB). Disease usually affects the lungs, but can involve other organs. TB in the lungs can spread through the air. Infection and disease are different: inactive infection causes no TB symptoms and is not contagious. Active disease may cause illness, although symptoms can be mild or absent. Symptoms alone cannot establish a diagnosis; testing and clinical assessment are needed.
Active TB disease and latent infection need different clinical assessment. People with latent TB have no TB symptoms and do not spread TB to others.
Species-informed illustration, not a microscopy reconstruction. Colours, layer thicknesses, and molecule sizes and placement are schematic. Viewer motion does not represent bacterial motility. Scientific review pending.
Source check: 2026-09-16. Educational content; independent scientific review remains pending.