Active transmission of pathogens is commonly referred to as what type of transmission?

Active transmission of pathogens is commonly referred to as biological transmission. This type of transmission involves the pathogen being biologically altered in a vector (such as insects) before it is transmitted to a host. For instance, in the case of malaria, the parasite undergoes part of its life cycle within the mosquito, and then the mosquito injects the parasite into a human host during a blood meal. This reflects an active process where the vector plays a crucial role in facilitating the disease's transmission.

In contrast, passive transmission would imply that the pathogen is transferred from one host to another without any multiplication or developmental change in the vector. Mechanical transmission refers to the transportation of pathogens on the surface of an insect or through contacts, such as when flies carry pathogens on their feet but do not undergo any biological change. Environmental transmission typically refers to pathogens being spread through environmental factors like water or soil without the need for a biological vector. Thus, biological transmission is the most accurate term describing the active process of pathogen transmission through a living vector.