Tuberculosis (TB)

A bacterial infection that usually affects the lungs. It spreads through the air and is curable with a full course of antibiotics.

InfectionLungsLast updated: 21 October 2026

Quick Summary

Primary Symptoms

A cough lasting more than 2 weeks, fever, night sweats, weight loss and tiredness. Sometimes coughing up blood.

Common Treatments

A combination of antibiotics taken every day for at least 6 months, free under India's national TB programme.

Risk Factors

Close contact with someone with TB, HIV, diabetes, malnutrition, smoking, alcohol use and crowded living conditions.

OverviewSymptomsCausesTreatmentFAQ

Overview

Tuberculosis is caused by the bacterium Mycobacterium tuberculosis. When a person with TB of the lungs coughs or sneezes, tiny droplets with bacteria get into the air and others can breathe them in.

Many people carry the bacteria without being ill (latent TB). Active TB develops when the immune system can't keep it under control. TB is common in India, but it can be cured, and treatment is free at government health centres.

Symptoms

Long-lasting cough

A cough for more than two weeks, sometimes with phlegm or blood.

Fever and night sweats

Evening fever and heavy sweating at night are common.

Weight loss and tiredness

Losing weight without trying, poor appetite and feeling weak.

Chest pain

Pain in the chest, especially when breathing or coughing.

Causes & Risk Factors

Biological Causes

Infection with Mycobacterium tuberculosis, spread through the air. TB usually affects the lungs but can affect other parts of the body, such as lymph nodes, bones, the brain and the spine.

Key Risk Factors

  • Weak immune system HIV, diabetes, malnutrition and some medicines make active TB more likely.
  • Close contact Living with or caring for someone with untreated lung TB.
  • Smoking and alcohol Both increase the risk of TB and of worse outcomes.

Management & Treatment

01. Testing

Sputum tests, a chest X-ray and rapid molecular tests confirm TB and check for drug resistance.

02. Antibiotic course

Usually four medicines at first (isoniazid, rifampicin, pyrazinamide, ethambutol), then fewer, for at least six months.

03. Finish the full course

Stopping early can bring TB back and cause drug-resistant TB. Health workers support patients to complete treatment.

Frequently Asked Questions

Is TB curable?
Yes. Most people are cured if they take the full course of medicines exactly as prescribed.
Am I infectious during treatment?
People with lung TB usually stop being infectious after a few weeks of correct treatment, but must still finish the course.
Where can I get treatment in India?
TB tests and medicines are free at government health centres under the National TB Elimination Programme.

Sources and further reading

Last updated 21 October 2026. For more detail, see these trusted health organisations.