Final answer:
Mechanical transmission through a 'mechanical vector' occurs when the vector carries the pathogen on its body without being infected, distinguishing it from 'biological transmission' where the pathogen grows inside the vector. This vector-based spread of pathogens is a critical pathway for the dissemination of diseases like Lyme disease and malaria.
Step-by-step explanation:
Mechanical transmission, where an arthropod carries a pathogen from one host to another without being infected itself, is known as mechanical vector transmission. This type of transmission occurs when the vector, such as mosquitoes, ticks, or flies, carries the pathogen on its body rather than hosting the pathogen internally. In contrast, biological transmission involves the pathogen being inside the vector, growing, and reproducing, and then being transmitted through biting.
Examples of diseases that are transmitted through vectors include Lyme disease, where ticks act as the vectors for the B. burgdorferi bacteria, and malaria, transmitted by mosquito vectors. An interesting case is mechanical transmission via indirect contact, where a pathogen is transferred through fomites, inanimate objects that can carry infectious agents, such as bedbugs on luggage or in cargo holds of planes.