Lyme Disease Ecological Cascade Simulator | Cary Institute 35-Year Model

Leaf-Litter Micro-Habitat Simulation (Year 1)

Acorns Mice Larval Ticks Infected Nymphs Deer

Scrub Year: Y 1.0

10-Year Trophic Lag Trajectory & Vector Infection Density

DON: Density of Infected Nymphs / 100m²

Y1Y2Y3Y4Y5Y6Y7Y8Y9Y10

Acorn Mast Index

2.1

Baseline

Mice / Hectare

Normal

Infected Nymphs/100m²

14.2

Standard Risk

Deer / km²

Standard Herd

Borrelia Infection Prevalence: 28.4%

Predicted Human Lyme Exposure Index: Moderate

Key Research Finding (Cary / PNAS):

Year t Mast → Year t+1 Mouse Surge (+250%).
Year t+2 Spike in Borrelia-infected nymphs (~40% surge).
Deer Abundance Paradox: Deer feed adult ticks but show zero statistical link ($R^2=0.018, p=0.42$) with nymph density or human cases.

Predictor Variable	Lag	Effect on Nymphs	P-Value
Mouse Density	1 Year	+38.8% Surge	< 0.001
Acorn Mast Index	2 Years	+42.1% Surge	< 0.001
Deer Abundance	1-3 Yrs	No Link (-1.2%)	0.42 (N.S.)