Holuwarkemmy/Spatial-Risk-Analysis-of-cVDPV2-Poliovirus-in-Nigeria

# Spatial Risk Analysis of Circulating Vaccine-Derived Poliovirus Type 2 (cVDPV2) in Nigeria ## 1. Introduction Nigeria has made significant progress towards polio eradication; however, the continued circulation of circulating vaccine-derived poliovirus type 2 (cVDPV2) remains a major public health concern. Persistent outbreaks are often driven by immunity gaps, high population concentration, and uneven surveillance performance, necessitating targeted and data-driven responses. Traditional tabular surveillance reports offer limited insight into where transmission risk is concentrated and how interventions should be prioritised geographically. Spatial analysis provides a powerful means of transforming surveillance data into actionable intelligence for immunisation planning and outbreak prevention. This project applies GIS-based spatial analysis and interactive data visualisation to assess cVDPV2 risk at Local Government Area (LGA) level in Nigeria, producing a composite risk index and an operational decision-support dashboard. ## 2. Aim and Objectives ### Aim To identify, classify, and visualise LGA level cVDPV2 transmission risk in Nigeria in order to support targeted public health interventions. ### Objectives • Aggregate ward-level cVDPV2 case data to the Local Government Area (LGA) level and integrate population density to assess transmission potential. • Develop a composite spatial risk index to classify LGAs by cVDPV2 transmission risk. • Visualise and communicate high-risk LGAs through an interactive dashboard to support targeted immunisation and surveillance planning. ## 3. Data Sources ### Datasets Used • Ward level cVDPV2 Surveillance Data • GRID3 Nigeria LGA boundary shapefile • Population Density Raster for under 5 years ## 4. Methodology ### 4.1 Spatial Data Processing (QGIS) • Harmonise and clean all spatial datasets, ensuring consistent coordinate reference systems and standardised LGA and ward identifiers. • Perform spatial j …