Sylvatic cycle

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The sylvatic cycle, also enzootic or sylvatic transmission cycle, is a portion of the natural transmission cycle of a pathogen. Sylvatic refers to the occurrence of a subject in or affecting wild animals. The sylvatic 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 a "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. [1] [2]

Examples of pathogens that contain a sylvatic cycle include trichinosis, [3] dengue viruses, [4] Yersinia pestis , [2] Chagas disease, [1] [5] and rabies. [6]

See also

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<span class="mw-page-title-main">Urban plague</span>

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References

  1. 1 2 Fernandes O, Mangia RH, Lisboa CV, et al. (1999). "The complexity of the sylvatic cycle of Trypanosoma cruzi in Rio de Janeiro state (Brazil) revealed by the non-transcribed spacer of the mini-exon gene". Parasitology. 118 (2): 161–6. doi:10.1017/s0031182098003709. PMID   10028530. S2CID   2124778.
  2. 1 2 Plague: Yersinia pestis Archived 2008-01-13 at the Wayback Machine
  3. Schmitt N, Saville JM, Greenway JA, Stovell PL, Friis L, Hole L (1978). "Sylvatic trichinosis in British Columbia: potential threat to human health from an independent cycle". Public Health Rep. 93 (2): 189–93. PMC   1431877 . PMID   635095.
  4. Vasilakis N, Holmes EC, Fokam EB, et al. (2007). "Evolutionary processes among sylvatic dengue type 2 viruses". J. Virol. 81 (17): 9591–5. doi:10.1128/JVI.02776-06. PMC   1951459 . PMID   17553878.
  5. "EPIDEMIOLOGY OF CHAGAS DISEASE". www.dbbm.fiocruz.br.
  6. Sudhi Ranjan Garg (2013). Rabies in Man and Animals. Springer Science & Business Media. p. 15. ISBN   9788132216056.