An interactive journey through TB — from how it spreads to how it's treated. Explore anatomical diagrams, click hotspots, and test your knowledge.
▶ Try Interactive TB SimulationA bacterial infection that primarily attacks the lungs
Tuberculosis (TB) is caused by a bacterium called Mycobacterium tuberculosis. It mainly affects the lungs, but can also attack other parts of the body like the kidneys, spine, and brain.
TB spreads through the air when an infected person coughs, sneezes, or speaks. It is curable and preventable, yet remains one of the world's deadliest infectious diseases.
Understanding airborne transmission step by step
When a person with active TB disease coughs, tiny droplets containing TB bacteria are expelled into the air. Even singing or talking can release these droplets.
The droplet nuclei are extremely small (1-5 microns) and can remain suspended in the air for several hours, especially in poorly ventilated spaces.
A susceptible person breathes in the droplet nuclei, which travel deep into the lungs. The bacteria may then establish infection in the lung tissue.
Click on the highlighted areas to learn more
Understanding the difference between latent and active tuberculosis
The bacteria are in your body but your immune system is keeping them contained. You are not sick and cannot spread TB to others.
The bacteria have overwhelmed your immune system. You are sick with symptoms and can spread TB to others through the air.
Click on the highlighted areas of the body to learn about each symptom
Tap each glowing circle on the body to reveal symptom details.
Persistent low-grade fever, often in the evening, with accompanying chills. The fever may come and go over weeks. Temperature typically ranges from 37.5-38.5°C.
A cough that lasts 3 weeks or more is a key warning sign. It may produce sputum (phlegm) and in some cases, blood. The cough worsens over time without treatment.
Significant weight loss and decreased appetite are common as the body fights the infection. Patients may lose 5-10kg or more without trying. This is sometimes called "consumption."
Drenching night sweats that soak through clothing and bedding. These occur as the immune system battles the bacteria during sleep and are a hallmark sign of active TB.
TB treatment takes 6 months — here's the roadmap to a cure
Four drugs are taken daily: Isoniazid, Rifampicin, Pyrazinamide, and Ethambutol (HRZE). This powerful combination rapidly kills the majority of TB bacteria. Most patients stop being contagious within 2-3 weeks of starting treatment.
Two drugs continue: Isoniazid and Rifampicin (HR). This phase eliminates remaining bacteria that are slow-growing or dormant. Stopping early risks relapse and drug-resistant TB.
5 questions to check what you've learned about TB