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Animated scientific plate · zero dependency primitive

Yellow Fever Transmission Cycles, Step by Step

Forest reservoir to human victim. Sixteen steps through the African sylvatic cycle, American sylvatic cycle, savannah bridge cycle, spillover hosts, and the sentinel events that warn us.

Inline SVG Manual & autoplay Reference plate No CDN 16 steps T.M. Jones, Ph.D. · ORCID 0000-0001-7372-6345
Companion document
Yellow Fever: Complete Scientific Reference →

Virology, clinical phases, hemorrhagic disease, vaccine, and control strategy.

Teaching note
Yellow fever is a forest disease that visits people, not a human disease that occasionally visits forests. Steps 1–5 are the African sylvatic reservoir. Steps 6–9 are the American pattern and its sentinel events. Steps 10–13 are the savannah bridge cycle where outbreaks originate. Steps 14–16 frame risk, regional contrast, and the reservoir-versus-victim distinction that is the whole lesson. ←→ navigate · Space play/pause.
Module
Step 1 of 16
Location
Animated yellow fever transmission cycle plate An interactive SVG showing yellow fever virus transmission through African sylvatic cycles, American sylvatic cycles, incidental dead-end hosts, sentinel monkey die-offs, and African savannah bridge cycles. Sylvatic cycle, Africa regional reservoirs, canopy vectors, incidental humans Aedes canopy vector African nonhuman primates incidental human virus blocked Sylvatic cycle, Americas canopy vectors and sentinel events Haemagogus / Sabethes New World NHP sentinel die-off Savannah bridge Africa intermediate cycle semi-domestic Aedes forest edge village interface African sylvatic American sylvatic bridge cycle
Manual · ←→

1. Yellow fever persists in sylvatic cycles

The forest cycle is the reservoir machine: mosquitoes and nonhuman primates keep yellow fever virus moving.

Glossary

Yellow fever ecology is harder to teach than the clinical disease because it requires holding three transmission contexts simultaneously. These terms anchor each cycle before the animation walks through it.

Yellow fever virus (YFV)
A flavivirus maintained in sylvatic cycles involving mosquitoes and nonhuman primate hosts across Africa and the Americas.
Sylvatic cycle
A forest-associated transmission cycle in which wildlife hosts and canopy mosquitoes maintain the virus independently of human populations.
Aedes africanus and related
Canopy-associated African vectors involved in the African sylvatic cycle. Feeds on monkeys and occasionally humans at forest margins.
Haemagogus and Sabethes
Mosquito genera in the Americas that move yellow fever virus among New World primates in the American sylvatic cycle.
Amplifying reservoir
A host population that sustains or intensifies transmission. Nonhuman primates in both Africa and the Americas serve this role in the sylvatic cycle.
Dead-end host
A host that can be infected but does not efficiently transmit the virus onward. Unvaccinated humans and horses are dead-end hosts in yellow fever.
Spillover
Movement of pathogen from the reservoir cycle into an incidental host. Forest-margin contact is the primary spillover context.
Intermediate (bridge) cycle
In African savannah settings, semi-domestic Aedes vectors can link forest-edge primate hosts with human settlements, bridging sylvatic and urban contexts.
Sentinel event
An observable signal of transmission activity. Primate die-offs in the Americas are a sentinel event for yellow fever activity in the area.
Vaccination gap
Susceptibility created when people at risk of forest-margin exposure are unvaccinated. The 17D vaccine is highly effective; the gap is a logistics and coverage problem.

Citation and archival

Persistent identifier
doi.org/10.5281/zenodo.20018197

Zenodo deposit, version of record. ORCID 0000-0001-7372-6345.

Suggested citation

Jones, T. M. (2026). Yellow Fever Transmission Cycles, Step by Step: Animated Teaching Primitive. TJID3 Research. https://doi.org/10.5281/zenodo.20018197

Artifact profile
  • Single-file HTML, no CDN, no external scripts.
  • Inline SVG plate, sixteen captioned frames.
  • Saves and runs offline; archival under the 20-Year File standard.
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