Which of the following best defines a disease vector?

Which of the following best defines a disease vector?

• A. A living organism that transmits disease
• B. A disease-causing microbe
• C. Any agent that acts as a carrier or transporter
• D. A route of transmission

Answer: (C)

The main idea tested is what defines a disease vector: it is a living organism that carries and transmits a pathogen from an infected host to a susceptible one. This matters because it distinguishes the vector from the pathogen itself and from nonliving carriers or routes. A living organism that transmits disease explains how the pathogen is moved and enables us to target control measures, such as reducing breeding sites, using protective clothing, and applying repellents—practical steps EMS and disaster teams use after events that create favorable conditions for vectors. The other concepts aren’t as precise: a disease-causing microbe is the pathogen, not the carrier; a carrier or transporter that is not living would include objects or inanimate means, which aren’t vectors; and a route of transmission refers to the path the pathogen takes, not the capable carrier itself.

The main idea tested is what defines a disease vector: it is a living organism that carries and transmits a pathogen from an infected host to a susceptible one. This matters because it distinguishes the vector from the pathogen itself and from nonliving carriers or routes. A living organism that transmits disease explains how the pathogen is moved and enables us to target control measures, such as reducing breeding sites, using protective clothing, and applying repellents—practical steps EMS and disaster teams use after events that create favorable conditions for vectors. The other concepts aren’t as precise: a disease-causing microbe is the pathogen, not the carrier; a carrier or transporter that is not living would include objects or inanimate means, which aren’t vectors; and a route of transmission refers to the path the pathogen takes, not the capable carrier itself.