Tuberculosis

Tuberculosis (TB), also known as the "white death", or historically as consumption,[8] is an infectious disease usually caused by Mycobacterium tuberculosis (MTB) bacteria.[1] Tuberculosis generally affects the lungs, but it can also affect other parts of the body.[1] Most infections show no symptoms, in which case it is known as latent tuberculosis.[1] Around 10% of latent infections progress to active disease which, if left untreated, kill about half of those affected.[1] Typical symptoms of active TB are chronic cough with blood-containing mucus, fever, night sweats, and weight loss.[1] Infection of other organs can cause a wide range of symptoms.[9]

Quick facts: Tuberculosis, Other names, Specialty, Symptom... ▼

Tuberculosis
Other names	Phthisis, phthisis pulmonalis, consumption, great white plague
Chest X-ray of a person with advanced tuberculosis: Infection in both lungs is marked by white arrow-heads, and the formation of a cavity is marked by black arrows.
Specialty	Infectious disease, pulmonology
Symptoms	Chronic cough, fever, cough with bloody mucus, weight loss[1]
Causes	Mycobacterium tuberculosis[1]
Risk factors	Smoking, HIV/AIDS[1]
Diagnostic method	CXR, culture, tuberculin skin test, QuantiFERON[1]
Differential diagnosis	Pneumonia, histoplasmosis, sarcoidosis, coccidioidomycosis[2]
Prevention	Screening those at high risk, treatment of those infected, vaccination with bacillus Calmette-Guérin (BCG)[3][4][5]
Treatment	Antibiotics[1]
Frequency	25% of people (latent TB)[6]
Deaths	1.5 million (2020)[7]

Tuberculosis is spread from one person to the next through the air when people who have active TB in their lungs cough, spit, speak, or sneeze.[1][10] People with latent TB do not spread the disease.[1] Active infection occurs more often in people with HIV/AIDS and in those who smoke.[1] Diagnosis of active TB is based on chest X-rays, as well as microscopic examination and culture of body fluids.[11] Diagnosis of Latent TB relies on the tuberculin skin test (TST) or blood tests.[11]

Prevention of TB involves screening those at high risk, early detection and treatment of cases, and vaccination with the bacillus Calmette-Guérin (BCG) vaccine.[3][4][5] Those at high risk include household, workplace, and social contacts of people with active TB.[4] Treatment requires the use of multiple antibiotics over a long period of time.[1] Antibiotic resistance is a growing problem, with increasing rates of multiple drug-resistant tuberculosis (MDR-TB).[1]

In 2018, one quarter of the world's population was thought to have a latent infection of TB.[6] New infections occur in about 1% of the population each year.[12] In 2020, an estimated 10 million people developed active TB, resulting in 1.5 million deaths, making it the second leading cause of death from an infectious disease after COVID-19.[13] As of 2018, most TB cases occurred in the regions of South-East Asia (44%), Africa (24%), and the Western Pacific (18%), with more than 50% of cases being diagnosed in seven countries: India (27%), China (9%), Indonesia (8%), the Philippines (6%), Pakistan (6%), Nigeria (4%), and Bangladesh (4%).[14] By 2021, the number of new cases each year was decreasing by around 2% annually.[13][1] About 80% of people in many Asian and African countries test positive, while 5–10% of people in the United States test positive via the tuberculin test.[15] Tuberculosis has been present in humans since ancient times.[16]