KRISTAL DALE F. CORPUZ – #6536448
The transmission pattern of pathogen by mosquitoes as the vector (organism that could transmit a pathogen) and/or as definitive host (harbors the parasite for sexual reproduction and development) refers to the process wherein a pathogen is transferred or transmitted to a susceptible organism usually serving as an intermediate host (harbors the larval stage or asexual form of pathogen) that could lead to the manifestations of a mosquito-borne disease.
By means of transmission mechanism, a pathogen can be transmitted via [i] parent-to-offspring (vertical transmission), [ii] biting (horizontal transmission), and [iii] mating of mosquitoes (venereal transmission). Parent-to-offspring transmission gives way for the pathogen from the adult mosquito to be transferred directly either to the eggs or in the embryo; Through biting or blood-meal, the mosquito can either inject the pathogen inside another organism (e.g. human) and undergo intrinsic incubation until the onset of symptoms of a disease, or the other way around to which the mosquito ingests the pathogen from human and undergo extrinsic incubation inside the mosquito; And in terms of mating, adult mosquitoes can be both infected by the pathogen present in either of them.
Upon ingestion, depending on the pathogen, different mosquito parts or compartments (oral, gut, salivary gland, fecal, hemolymph) are infected leading to different routes to which transmission is made possible. Although it could be simply passing the pathogen to another organism, it can also be influenced by some factors including changes in the environment (climate, geography, temperature, other biotic and abiotic components), vector or mosquito behavior (host-seeking and biting, extrinsic incubation, sporogonic cycle, distribution and movement, longevity, susceptibility to pathogen), societal changes, as well as population movement and density especially of the intermediate hosts. These factors play importance in the whole transmission pattern and cycle because certain changes could be drivers for e.g. increased transmission rate, shortening of incubation period, erratic disease distribution and prevalence.