Watch the outbreak
Select Freehand / lasso, then drag to sketch curved walls. Return to your starting point to close a quarantine zone. People bounce off active walls.
Select Freehand / lasso, then drag to sketch curved walls. Return to your starting point to close a quarantine zone. People bounce off active walls.
Choose your population and disease conditions, then start your experiment.
Note: the time before someone becomes infectious is called the latent period. The incubation period is the time before symptoms appear, which may differ.
Experiment time is separate from how long a person remains infected.
Experiment settings lock during a run. Colours can be changed at any time. Reset to edit the other settings.
Change vaccination and quarantine conditions, then compare recorded outbreaks.
Test different vaccination rates. Save a result after each run to investigate how vaccination changes the outbreak.
| Run | Vaccinated | Ever infected | Peak infected | Time limit | Actual time | Stop reason | Exposed stage | Hotspot infections | Transmission events |
|---|---|---|---|---|---|---|---|---|---|
| No experiments saved yet. | |||||||||
Model transmission and evaluate prevention strategies.
Keep the population, starting infection count and movement speed the same. Change only the vaccination percentage. Does a higher vaccination rate usually reduce the number of people infected?
This is a simplified random-contact model, not a prediction of a real outbreak. Real diseases spread through different routes; vaccine protection, exposure, immunity and behaviour vary. The green vaccination counter counts currently healthy vaccinated people, while infection cases may still include vaccinated individuals if effectiveness is below 100%. Repeat each setting several times because chance matters.
Hotspots: choose a location icon, click to place it, then select a hotspot to edit radius, attraction or close it. Tracing: select Trace infections, then switch between Latest (most recent from → to), Chain (trace back to the infection source OR forward through everyone subsequently infected), and Full web (every recorded link). Select a figure to inspect its history in a separate panel beside the population, without covering the simulation. Disease stages: use the switch in Setup to enable the non-infectious exposed period. Freehand / lasso: drag to sketch curved walls; complete the loop near the starting point. Quarantine: switch walls on and off to compare spread. Run again: repeat with the same settings. Save result: store a run for comparison.