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The passive transfer of causative agents of disease, esp. by arthropods. This may be indirect, as when flies pick up organisms from excreta of humans or animals and deposit them on food, or direct, as when they pick up organisms from the body of a diseased individual and directly inoculate them into the body of another individual by bites or through open sores.See: vector
See also: transmission
1. transfer, as of an infection from one patient to another.
2. of nervous impulses. See neuromuscular transmission.
spread of infection by droplet nuclei or dust through the air. Without the intervention of winds or drafts the distance over which airborne infection takes place is short, say 10 to 20 feet.
by insect, either mechanically via a contaminated proboscis or feet, or biologically when there is growth or replication of the organism in the arthropod. See also trans-stadial.
involving a biological process, e.g. passing a stage of development of the infecting agent in an intermediate host. Opposite to mechanical transmission.
a form of vertical transmission via successive generations.
the disease agent is transferred directly by biting, sucking, chewing or indirectly by inhalation of droplets, drinking of contaminated water, traveling in contaminated vehicles.
the agent undergoes both development and multiplication in the transmitting vehicle.
the agent undergoes some development in the transmission vehicle.
the infectious agent is shed by the infected host in feces and acquired by the susceptible host through ingestion of contamined material.
lateral spread to others in the same group and at the same time; spread to contemporaries.
the transmitter is not infected in that tissues are not invaded and the agent does not multiply.
the agent multiplies in the transmission vehicle.
from one generation to the next, perhaps transovarially or by intrauterine infection of the fetus. Some retroviruses are transmitted in the germ line, i.e. their genetic material is integrated into the DNA of either the ovum or sperm.