Tuberculosis  (TB) is often thought of as a disease of the past, but an ongoing resurgence makes it very much an issue of the present day and age.

TB is caused by a bacterium, Mycobacterium tuberculosis, that the World Health Organization says infects one third of the world’s population. Between 5 and 10 percent of infected people develop the disease and become contagious at some point in their lives. (For those with HIV or AIDS, however, the rate is much higher.)

The disease usually develops in the lungs, although there are extra-pulmonary cases where the bacilli infect other parts of the body, usually the lymph nodes, bones, central nervous system, and cardiovascular and gastrointestinal systems. Major symptoms of TB are: prolonged cough, bloody expectorations, chest pain, and changes in a person’s general health status. Coughing, sneezing, talking, and spitting can all spread the bacilli into the air, where they can remain viable for several hours before being inhaled by another person.

Infographic by better-things.co.uk