Tuberculosis
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. It most often affects the lungs, but it can involve almost any organ. TB spreads through the air from a person with infectious pulmonary or laryngeal disease and is both preventable and curable.
At a glance
Quick facts
- Category
- Bacterial infectious disease
- Main route
- Airborne transmission
- Most common site
- Lungs
- Common symptoms
- Cough · fever · weight loss · night sweats
- Diagnosis
- WHO-recommended rapid tests
- Treatment
- Combination anti-TB medicines
Names & terminology
How this entity may be named or searched
- Canonical name
- Tuberculosis (TB).
- TB infection
- Infection without clinical TB disease; people with TB infection are not contagious.
- TB disease
- Active clinical disease caused by M. tuberculosis, pulmonary or extrapulmonary.
- Drug-resistant TB
- TB caused by organisms resistant to one or more key anti-TB medicines; regimen selection requires resistance testing and guideline-based care.
Structured entity profile
Clinical profile
Overview
TB develops when infection with Mycobacterium tuberculosis progresses to disease. People with TB infection have no symptoms and are not contagious, but some later develop TB disease, especially when immunity is weakened. [1] [4]
WHO estimated that 10.7 million people developed TB in 2024 and 1.23 million died from the disease, including 150,000 people with HIV. TB remains the leading cause of death from a single infectious agent globally. [1]
Symptoms and warning signs
Pulmonary TB commonly causes a prolonged cough, chest pain, fever, night sweats, fatigue, loss of appetite and weight loss; coughing up blood can occur. Extrapulmonary TB causes symptoms related to the affected organ and may be more difficult to recognize. [1]
SYMPTOM MATRIX
TB can be subtle for months — or severe when it involves the CNS, lungs or multiple organs
Symptoms depend on disease site, immune status and age.
- Prolonged cough
- Fever
- Night sweats
- Weight loss
- Fatigue or reduced appetite
- Enlarged lymph nodes
- Persistent back or joint pain
- Abdominal symptoms
- Headache or neurologic symptoms
- Pleural or pericardial disease
- Severe breathlessness
- Coughing significant blood
- Confusion or meningitis symptoms
- Severe illness in a young child
- Advanced HIV with systemic deterioration
Severe TB or TB meningitis requires urgent specialist evaluation and treatment.
Diagnosis
WHO recommends rapid diagnostic tests as initial tests for people with signs or symptoms of TB. Molecular tests can detect M. tuberculosis and, for some assays, resistance to important medicines much faster than conventional culture. [1] [2]
Sputum is commonly tested in pulmonary TB, but specimen choice depends on age and disease site. Chest radiography can support triage and diagnosis but does not establish TB by itself. Tests for TB infection identify immune sensitization and are mainly used to determine who may benefit from preventive treatment after active disease has been excluded. [2] [4]
Diagnostic pathway
Confirm TB and detect resistance early
The diagnostic pathway should identify both the organism and the treatment-relevant resistance pattern.
A normal or non-specific chest X-ray does not exclude TB, especially in children or immunocompromised patients.
Drug-resistant tuberculosis
Drug-resistant TB can be transmitted directly or emerge when treatment is ineffective or incomplete. Rapid detection matters because standard drug-susceptible regimens may fail. WHO treatment recommendations increasingly use shorter all-oral regimens for eligible drug-resistant disease, selected according to resistance pattern and clinical context. [2] [3]
Treatment and management
Drug-susceptible TB is treated with a combination of anti-TB medicines. Depending on eligibility and national guidance, treatment may use a standard six-month regimen or a shorter WHO-recommended regimen. Drug-resistant TB requires different combinations based on resistance results, prior exposure and disease severity. [1] [3]
Patient-centred support is part of treatment: clinicians monitor response, adverse effects and adherence and address nutrition, mental health, social barriers and comorbid conditions. People living with HIV need coordinated TB and antiretroviral care, including attention to drug interactions and timing. [1] [3]
Treatment & care hub
Effective TB care combines the right regimen with support to complete it
Treatment failure and ongoing transmission become more likely when resistance or adherence barriers are missed.
Combination therapy
Use a WHO-recommended multi-drug regimen for the full planned duration.
Use an appropriate all-oral regimen
Rapid resistance testing helps select shorter or longer regimens according to eligibility and resistance.
Coordinate care
Treat TB alongside HIV, diabetes, undernutrition and other clinically important conditions.
Reduce treatment interruption
Counselling, adverse-effect management and social support improve the chance of completing curative treatment.
National TB programmes adapt WHO recommendations to local medicines, diagnostics and resistance patterns.
Prevention and TB infection
Prevention includes early diagnosis and effective treatment of infectious TB, ventilation and respiratory protection in higher-risk settings, contact investigation, BCG vaccination in national programmes and TB preventive treatment (TPT) for eligible people at high risk of progression from infection to disease. WHO specifically prioritizes people living with HIV, household contacts and other risk groups for TPT. [1] [4]
TB in African health systems
TB and HIV remain closely linked in many African countries. Nigeria and the Democratic Republic of the Congo are among the eight countries that together accounted for about two thirds of global TB cases in 2024. Delayed diagnosis, undernutrition, HIV, diabetes and treatment access can all influence individual and community outcomes. [1]
Global burden · WHO 2026
Tuberculosis remains the leading cause of death from a single infectious agent
WHO estimates for 2024 include adults and children in every region of the world.
Common questions
Frequently asked questions
No. People with TB infection are not contagious. Transmission is mainly associated with active pulmonary or laryngeal TB.
Yes. Most drug-susceptible TB can be cured when an effective combination regimen is taken for the full recommended duration.
WHO recommends rapid diagnostic tests as the initial tests for people with signs or symptoms of TB, supported by appropriate microbiology, imaging and clinical assessment.
The preferred term is TB infection: a person is infected with TB bacteria but has no symptoms of TB disease and is not contagious.
HIV increases the risk that TB infection will progress to disease and can make extrapulmonary or disseminated presentations more likely.
Sources
- WHO — Tuberculosis fact sheet, 24 March 2026
- WHO — Consolidated guidelines on tuberculosis, Module 3: Diagnosis — rapid diagnostics, 3rd ed.
- WHO — Consolidated guidelines on tuberculosis, Module 4: Treatment and care, 2nd ed., 25 September 2026
- WHO — Consolidated guidelines on tuberculosis, Module 1: Preventive treatment, 2nd ed.
This article is based on trusted medical sources and is awaiting clinician review. It is not a substitute for personalized medical advice.