Figure. Spatial distribution of chronic wasting disease in White-tailed Deer sampled in Wisconsin (February–April 2002). Locations for sampled deer were recorded by using the Wisconsin Public Land Survey System (township-range-section); analysis was conducted on pooled 4X4 sections (41 km2), as indicated by the dashed grid lines. Prevalence, 95% confidence limits (CI), and sample size for each quadrant are indicated, as well as sample size only for quadrants in which positive deer were not detected. A cluster of higher than expected prevalence was detected in the north-central region of the sampling area indicated by shading (prevalence 9.4%, 95% CI 5.0% to 16.0%, n=127). The asterisk indicates the quadrant in which the three initial positive deer were found. The circle represents the targeted surveillance area.