Zoonotic Spillover & Host Adaptation Simulator (2D)

This simulator models the two-stage process behind every zoonotic pandemic: a reservoir animal population (amber cluster) sits near a human population (grey/red/blue contact grid), and periodic contact events give the pathogen a dose-response chance of jumping the species barrier, governed by receptor-binding affinity and exposure dose. Once a spillover succeeds, the same affinity feeds a stochastic branching process across a human contact network, and a live extinction-probability calculation reports the real-time chance the chain becomes a major outbreak rather than fizzling out — exactly the calculation that explains why most spillovers (from H5N1 to Nipah) never became pandemics, while a rare few (1918 flu, SARS-CoV-2) did. This 2D edition renders the same populations and the same equations as a pannable, zoomable flat contact map instead of an orbiting 3D scene.