What is airborne transmission?

• A. Disease transmitted via surfaces only
• B. Disease transmitted through small, <5 microns, particulates through the air over time and distance
• C. Disease transmitted by direct contact with skin
• D. Disease transmitted only by water contamination

Answer: (B)

Airborne transmission means pathogens are carried by tiny particles that stay suspended in the air and can travel over time and distance, reaching people who are not in immediate contact with the source. These particles are typically very small, about 5 microns or smaller, allowing them to be inhaled deeply into the lungs and to linger in the environment, spreading beyond close-range contact. This contrasts with other routes like fomite transmission (via contaminated surfaces), direct skin-to-skin contact, or waterborne transmission, which involve different pathways and don’t rely on inhalation of dispersed aerosols. Examples of airborne diseases include infections such as tuberculosis, measles, and varicella, which spread through these small, inhaled particles.