Geographic Information Systems (GIS) have consolidated as essential analytical tools for addressing public health and urban security challenges, yet the available evidence remains fragmented due to methodological heterogeneity and geographical inequalities. This study applied a fused pipeline integrating Systematic Mapping (SM) and Systematic Review (SR), grounded in the PICOS (health) and SPICE (security) frameworks, which systematically reduced an initial corpus of 7,106 records to 65 core articles through multi-layered screening and a 1–4 technical quality scoring matrix. Results indicate sustained growth in scientific production, peaking in 2023 (32.3% of all publications). Geographically, research is concentrated in Asia (33.8%) and North America (16.9%), while Africa (12.3%) and South America (9.2%) remain underrepresented. Methodologically, a dominant core was identified around accessibility metrics (36.9%) and spatial autocorrelation (27.7%), with a prevalence of cross-sectional observational designs and limited adoption of advanced models such as Bayesian inference and machine learning (9.2%). The technological ecosystem is dominated by ArcGIS (61.5%) and QGIS (23.1%), complemented by open-source environments such as R, Python, and SaTScan. Overall, the fused SM+SR pipeline provides a transparent and replicable framework that exposes key strengths—high spatiotemporal resolution and scalability—while revealing critical gaps related to data openness and reproducible validation, offering concrete guidelines for future research and evidence-based policymaking.