Which presentation indicates an infectious disease acquired through indirect transmission?

Which presentation indicates an infectious disease acquired through indirect transmission?

• A. Malaria following exposure in a mosquito-infested area
• B. Influenza contracted via airborne droplets
• C. Tuberculosis transmitted by coughing
• D. Strep throat spread by direct contact

Answer: (A)

Indirect transmission occurs when a pathogen passes to a new host through an intermediary rather than by direct contact or immediate exposure to respiratory droplets. Malaria fits this because a mosquito acts as the vector: the parasite is carried by the mosquito and transmitted to a person through a bite after the mosquito feeds on an infected host. The other scenarios involve direct spread from person to person or via respiratory droplets, not via an intermediary vector. So the malaria scenario best illustrates indirect transmission.

Indirect transmission occurs when a pathogen passes to a new host through an intermediary rather than by direct contact or immediate exposure to respiratory droplets. Malaria fits this because a mosquito acts as the vector: the parasite is carried by the mosquito and transmitted to a person through a bite after the mosquito feeds on an infected host. The other scenarios involve direct spread from person to person or via respiratory droplets, not via an intermediary vector. So the malaria scenario best illustrates indirect transmission.