Which option describes indirect transmission?

• A. Direct contact
• B. Indirect contact
• C. Airborne transmission
• D. Vector-borne transmission

Answer: (B)

Indirect transmission happens when the pathogen moves from one person to another via an intermediary, rather than through direct person-to-person touch. Indirect contact specifically refers to transferring infection by touching a contaminated object or surface (a fomite) or by another intermediary that carries the pathogen to the next host. For example, touching a door handle that a contagious person touched and then touching your face can transfer the pathogen.

Airborne transmission and vector-borne transmission are separate routes: airborne involves infectious particles traveling through the air to be inhaled, and vector-borne involves a living carrier like a mosquito transmitting the pathogen. These are different mechanisms from indirect contact, which is why indirect contact best describes the concept asked.