Tuberculosis (TB) is caused by a bacterium called Mycobacterium tuberculosis. This bacterium most commonly affects the lungs, but it can also affect other parts of the body.
How TB Spreads
TB is primarily spread through the air. When a person with active TB in their lungs coughs, sneezes, speaks, or sings, they release tiny droplets containing the bacteria. These droplets can then be inhaled by others nearby, leading to infection. A person only needs to inhale a few of these germs to become infected. The World Health Organization (WHO) states that 10 million people contract TB annually. https://www.who.int/health-topics/tuberculosis
Key Facts about TB Transmission
- Airborne Transmission: TB bacteria are spread through the air, similar to how colds or the flu spread. https://www.cdc.gov/tb/causes/index.html, https://my.clevelandclinic.org/health/diseases/11301-tuberculosis, https://medlineplus.gov/tuberculosis.html, https://www.webmd.com/lung/understanding-tuberculosis-basics
- Close Contact: The risk of infection is higher with close and prolonged contact with an individual who has active TB. https://www.nhs.uk/conditions/tuberculosis-tb/
- Lung TB is Most Contagious: While TB can affect other organs, lung TB is the most contagious form. https://www.nhsinform.scot/illnesses-and-conditions/infections-and-poisoning/tuberculosis-tb/
