Explanation:

According to the World Health Organisation(WHO), the disease which causes the death of the largest number of people today is Tuberculosis.
The bacteria that cause TB are spread when an infected person coughs or sneezes.
Most people infected with the bacteria that cause tuberculosis don't have symptoms. When symptoms do occur, they usually include a cough (sometimes blood-tinged), weight loss, night sweats and fever.
Treatment isn't always required for those without symptoms. Patients with active symptoms will require a long course of treatment involving multiple antibiotics.