TB transmission can occur through which mechanism described here?

• A. Through aerosols from sputum
• B. Through water runoff
• C. Through skin contact
• D. Through foodborne transmission

Answer: (A)

TB is transmitted when people inhale aerosols containing Mycobacterium tuberculosis that are expelled by an infected person. When someone with active pulmonary TB coughs, sneezes, talks, or sings, tiny particles are released into the air. These aerosolized particles can stay suspended and travel through the room, and others who breathe them in can become infected as the bacteria reach the lungs or airways. Other routes—water runoff, skin contact, or foodborne transmission—do not efficiently spread TB because the bacteria are not typically transmitted via contaminated surfaces, fluids, or ingestion in the absence of inhalation. Transmission risk increases with close, prolonged exposure in poorly ventilated spaces, while good ventilation helps reduce it.