Spatio-temporal analysis of measles in Morocco (2023-2024): GIS-based hotspot detection and evidence-driven priorities for elimination

Abstract

Measles remains a significant public health concern in Morocco despite the availability of effective vaccination. Recent outbreaks highlight the need for improved understanding of its spatial distribution and underlying risk factors to better support targeted public health interventions.The retrospective observational study analyses the spatio-temporal distribution of measles cases in Morocco over the period 2023-2024. Data were obtained from the Moroccan Ministry of Health and integrated with administrative geographic boundaries. Spatial analysis was conducted using Geographic Information Systems (QGIS) to map incidence patterns and identify regional variations. Comparative analysis of case distribution across regions was performed to detect heterogeneity in transmission intensity.The analysis revealed marked spatial heterogeneity in measles transmission across Morocco. Higher incidence levels were observed in the regions of Tangier-Tetouan- Al Hoceima, Oriental, Souss-Massa, and Beni Mellal-Khenifra, while moderate transmission was identified in Casablanca-Settat, Marrakech-Safi, and Rabat-Sale-Kenitra. Lower incidence was recorded in southern regions, including Draa-Tafilalet and Laayoune-Sakia El Hamra. These spatial patterns suggest the influence of contextual factors such as population mobility, vaccination coverage disparities, and access to healthcare services. The findings highlight a clear north-center versus south gradient in disease distribution.This study demonstrates the added value of spatial analysis for identifying high-risk areas and guiding targeted public health responses. The results emphasize the need to strengthen vaccination coverage and surveillance systems, particularly in high-incidence regions, to prevent future outbreaks. By providing a spatially explicit assessment of measles distribution, this study contributes to improving evidence-based decision-making for measles control and supports national efforts toward elimination in line with WHO targets.