Tuberculosis is a bacterial infection that can spread throughout the body from the lymph nodes and through the bloodstream, according to WebMD. If it becomes symptomatic, tuberculosis can kill the tissue of infected organs, potentially leading to death. It is also known by the shorthand name "TB."
The bacteria that causes tuberculosis can travel through the air, meaning that it can infect people in close proximity to an individual with the disease, according to WebMD. However, most people who are infected with the bacteria never exhibit symptoms, a state called a latent TB infection. Non-symptomatic infections are not contagious through the air. The latent tuberculosis infection can be become symptomatic if a person's immune system weakens, such as through aging or the development of another condition like HIV. The World Health Organization estimates that about one-third of the world population has a latent TB infection.
Traditionally, doctors treat tuberculosis with antibiotics, according to WebMD. However, certain newer forms of tuberculosis are resistant to multiple drugs, complicating treatment options. Symptoms of tuberculosis include coughing with bloody phlegm, low fever, shortness of breath, overall fatigue and a pain in the chest. Doctors can test patients with these symptoms who may have been exposed to tuberculosis to diagnose the disease.