An entomological vector is defined as which of the following?

An entomological vector is defined as which of the following?

• A. A pathogen that infects insects
• B. An insect or animal that transmits disease either actively or passively
• C. An organism that preys on other insects
• D. An insect that collects pollen

Answer: (B)

A vector is the organism that transfers a pathogen from one host to another, enabling disease spread. An entomological vector is an insect or other organism that can pass a pathogen to a susceptible host, and this transfer can happen in two ways. In active or biological transmission, the pathogen actually develops or multiplies inside the vector and is delivered to the host when the vector feeds or bites, as seen with malaria parasites in mosquitoes or dengue virus in Aedes mosquitoes. In passive transmission, the vector doesn’t support pathogen development; instead, the pathogen is carried on its body or in its gut and is transferred to a new host without the pathogen needing to complete a life cycle inside the vector, such as a fly picking up bacteria on its legs and contaminating food. This concept helps distinguish vectors from other roles. A pathogen that infects insects is just a pathogen, not a vector. A predator that preys on insects is unrelated to disease transmission, and a pollen-collecting insect is involved in pollination, not spreading disease.

A vector is the organism that transfers a pathogen from one host to another, enabling disease spread. An entomological vector is an insect or other organism that can pass a pathogen to a susceptible host, and this transfer can happen in two ways. In active or biological transmission, the pathogen actually develops or multiplies inside the vector and is delivered to the host when the vector feeds or bites, as seen with malaria parasites in mosquitoes or dengue virus in Aedes mosquitoes. In passive transmission, the vector doesn’t support pathogen development; instead, the pathogen is carried on its body or in its gut and is transferred to a new host without the pathogen needing to complete a life cycle inside the vector, such as a fly picking up bacteria on its legs and contaminating food.

This concept helps distinguish vectors from other roles. A pathogen that infects insects is just a pathogen, not a vector. A predator that preys on insects is unrelated to disease transmission, and a pollen-collecting insect is involved in pollination, not spreading disease.