Anthropogenic activities and the regional distribution of leprosy in Senegal: an ecological analysis of agricultural and mining activities

Objectives

To investigate the association between anthropogenic environmental changes, particularly agricultural and mining activities, and the spatial distribution of leprosy in Senegal.

Methods

An ecological study was conducted across the 14 administrative regions using national surveillance data and cases detected through active case-finding (2020–2022). Agricultural intensity was scored from 0 (urban) to 4 (very high), and mining activity was classified by regional intensity. Associations with leprosy case counts were assessed using correlation, ANOVA, and linear regression.

Results

Agricultural intensity was strongly associated with regional leprosy case counts (Spearman’s ρ = 0.915, p < 0.001). Linear regression explained 48.6% of case-count variation (R² = 0.486, p = 0.006), with each unit increase in agricultural intensity associated with 81.85 additional cases. The Bassin Arachidier accounted for 68.2% of cases across four of 14 regions. Mining activity was also positively associated with leprosy cases (ρ = 0.647, p = 0.012), with significant differences across mining levels (ANOVA: F₂,₁₁ = 4.23, p = 0.041).

Conclusions

Higher agricultural and mining intensity were associated with greater regional leprosy case counts. These ecological findings support further investigation of anthropogenic environmental factors in leprosy distribution.