Tuberculosis (TB) is an airbone bacterial infection caused by Mycobacterium tuberculosis. TB can be acquired by breathing contaminated air droplets coughed or sneezed by a person nearby who has active Tuberculosis. Humans can also get ill with TB by ingesting unpasteurized milk products contaminated with Mycobacterium bovis, also known as Bovine Tuberculosis. The most common form of the infection is pulmonary TB which affects the lungs. In some cases, the bacteria can also attack the lymphatic system, central nervous system, urogenital area, joints, and bones.
Mycobacterium tuberculosis is present worldwide and typically spreads in cramped, overcrowded conditions. There is no evidence that pulmonary TB is more easily transmitted in airplanes or other forms of public transportation. Long-term travellers, those with a weakened immune system or visiting friends and relatives (VFR travellers) in areas where Tuberculosis is endemic are at risk. Humanitarian and healthcare personnel working in communities with active TB are also at increased risk. Persons with active TB should not travel.
The majority of persons with the illness (90% to 95%) have latent TB infection (LTBI) and do not exhibit any symptoms. The bacteria can remain inactive for many years and the chance of developing active TB diminishes over time.
Persons with active TB have symptoms which include excessive coughing (sometimes with blood), chest pain, general weakness, lack of appetite, weight loss, swollen lymph glands, fever, chills, and night sweats. It can be misdiagnosed for bronchitis or pneumonia. If untreated, active TB can fatal.
Tuberculosis treatment involves taking antibiotics for a minimum of 6 months. Drug-resistant TB is a major concern as an increasing number of people are no longer able to be treated with previously effective drugs. Due to misuse of antibiotic therapies, patients can develop multi-drug resistant Tuberculosis (MDR TB). When a second line of antibiotics fail to cure the multi-drug resistant infection, it is known as extensively drug-resistant Tuberculosis (XDR TB).
Mycobacterium tuberculosis images, life cycle, and distribution maps:
Information last updated: January 2020