Answer:
Tuberculosis .
Step-by-step explanation:
Tuberculosis is a disease that most commonly affects lungs. It is infectious and can be spread through air, if one inhales the infected air.
Its symptoms are coughing and bloody sputum as well as weight loss. Smokers also have increased chances of being affected by tuberculosis. The disease can also spread onto other organs of the human body.
There is a type of tuberculosis that shows no symptoms and it is called latent tuberculosis.