What are the two mechanisms of airborne transmission?

• A. Droplet nuclei and dust.
• B. Direct contact.
• C. Vehicle borne.
• D. Vector borne.

Answer: (A)

Airborne transmission happens when infectious agents travel through the air and are inhaled. The two mechanisms involved are droplet nuclei and dust.

Droplet nuclei are the tiny residues left when respiratory droplets evaporate; these minuscule particles can stay suspended in air for extended periods and be carried by air currents to affect others even at a distance from the source. Dust can also harbor pathogens and be inhaled, spreading infection through the airways.

These mechanisms differ from other routes: direct contact requires physical touch, vehicle-borne involves contaminated objects, and vector-borne relies on another organism to transmit the pathogen.