Ecology of Malaria Mortality: A Spatiotemporal Mapping Approach

Area of Science:

• Paleopathology
• Historical Epidemiology
• Environmental History

Background:

• 19th-century Ontario experienced significant settlement expansion and landscape transformation.
• Understanding the spatiotemporal dynamics of disease ecology is crucial in historical contexts.
• Settler-colonial practices profoundly impacted disease transmission patterns.

Purpose of the Study:

• To examine the spatiotemporal ecology of probable malaria mortality in 19th-century southern Ontario.
• To evaluate how settlement, landscape change, and infrastructure influenced malaria transmission risk.
• To analyze the role of environmental and anthropogenic factors in structuring disease ecology.

Main Methods:

• Geographic Information Systems (GIS) analysis of geocoded malaria-attributed deaths (1869-1900).
• Spatial analysis of mortality in relation to historical settlements, railways, and wetlands.
• Statistical modeling (negative binomial regression, generalized additive models) to identify predictors of malaria mortality density.

Main Results:

• Malaria mortality was spatially clustered but became less concentrated over time.
• Mortality locations shifted away from wetlands as drainage increased.
• Settlement proximity was the primary predictor of malaria mortality density, independent of wetland proximity.

Conclusions:

• Malaria risk reorganized from environmental ecologies to anthropogenic landscapes shaped by colonial activities.
• Disease transmission was embedded in settlement practices rather than static environmental features.
• Spatiotemporal GIS approaches are valuable for interpreting past disease ecologies.