Share +. Text A A A. Rheumatoid arthritis (RA) is an autoimmune disease where the body's immune system attacks normal joint tissues, causing inflammation of the joint lining. This inflammation of the joint lining (called the synovium) can cause pain, stiffness, swelling, warmth, and redness.ext A A A. Rheumatoid arthritis (RA) is an autoimmune disease where the body's immune system attacks normal joint tissues, causing inflammation of the joint lining.
Tuberculosis. Tuberculosis (TB) is an infectious disease caused by a bacterium that usually attacks the lungs. TB is spread through the air from one person to another. The bacteria are put into the air when a person with active TB disease of the lungs or throat coughs, sneezes, speaks, or sings.
Tuberculosis may be the only communicable dis-. ease with obligate airborne transmission â an in-. fection that, under natural conditions, is initiated. only through aerosols deposited in the distal lung. Diseases with preferentially airborne transmission. are caused by agents that can naturally initiate infec-.