The sylvatic cycle, also enzootic

Enzootic

Enzootic is the non-human equivalent of endemic and means, in a broad sense, "belonging to" or "native to", "characteristic of", or "prevalent in" a particular geography, race, field, area, or environment; native to an area or scope....

or sylvatic transmission cycle, is a portion of the natural transmission cycle of a pathogen

Pathogen

A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...

. The sylvatic

Sylvatic

Sylvatic is a scientific term referring to diseases or pathogens affecting only wild animals. In the context of animal research, its opposite is domestic, which refers to pets, farm animals or other animals which do not dwell in the wild.*Examples: sylvatic rabies; sylvatic and domestic bacterial...

 cycle is the fraction of the pathogen population's lifespan spent cycling between wild animals and vectors. Humans are usually an incidental or dead-end host, infected by a vector. This is opposed to an "domestic", or "urban", cycle, in which the pathogen cycles between vectors and non-wild, urban, or domestic animals; humans may have differing infection rates from these cycles due to transmission efficiencies and environmental exposure levels.

Examples of pathogens that contain a sylvatic cycle include trichinosis

Trichinosis

Trichinosis, also called trichinellosis, or trichiniasis, is a parasitic disease caused by eating raw or undercooked pork or wild game infected with the larvae of a species of roundworm Trichinella spiralis, commonly called the trichina worm. There are eight Trichinella species; five are...

, dengue virus

Dengue virus

Dengue virus in one of four serotypes is the cause of dengue fever. It is a mosquito-borne single positive-stranded RNA virus of the family Flaviviridae; genus Flavivirus...

es, Yersinia pestis

Yersinia pestis

Yersinia pestis is a Gram-negative rod-shaped bacterium. It is a facultative anaerobe that can infect humans and other animals....

,, and Chagas disease

Chagas disease

Chagas disease is a tropical parasitic disease caused by the flagellate protozoan Trypanosoma cruzi. T. cruzi is commonly transmitted to humans and other mammals by an insect vector, the blood-sucking insects of the subfamily Triatominae most commonly species belonging to the Triatoma, Rhodnius,...