Overview and Purpose 

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The Mapping and Epidemiology Work Package is a core component of the PACTS project, focused on quantifying geographical and physical barriers to Sickle Cell Disease (SCD) care in sub-Saharan Africa. It uses epidemiological and geospatial methods to explore how physical access (and related factors) affects SCD patients’ ability to obtain care. The goal is to produce nationally representative data and insights that reveal the physical and cost barriers faced by SCD patients in accessing health services. This evidence will complement clinical and community findings from other PACTS work streams, helping to inform strategies to improve access to SCD care. 

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Current Geospatial Data Collection Activities  

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(NIGERIA) 

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We are currently conducting a mapping study in Nigeria, with planned expansion to other partner countries. Using random sampling, the study captures data from diverse settings—urban, peri-urban, and remote rural areas. Core activities include: 

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• Health Facility Mapping: Leveraging Geographic Information Systems (GIS), we geolocate all facilities providing SCD care, including distance from health facilities. 

• Patient Location Data: We collect anonymized residential coordinates of SCD patients in care, linking them to facility data to support spatial analysis and accessibility assessment. 

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Access Assessment and Comparative Analysis

 

Using the assembled GIS database, we are assessing physical access to care and analyzing disparities across population groups and regions. Key components include: 

• Estimating Distance and Travel Time: We calculate how far and how long it takes for patients to reach the nearest SCD care facility, factoring in road networks and mode of transportation. 

• Identifying Geographic Barriers: We focus on the geographic difficulty patients face in reaching care—such as living in remote locations with poor transport links, rough terrain, or long travel distances to the nearest facility. This includes areas with limited road access, lack of public transportation, or sparse distribution of SCD services, all of which significantly hinder timely access to care.

• Combining Data Layers: The analysis merges facility locations, patient distribution, and publicly available geospatial data (e.g., population density, infrastructure) to create a detailed view of accessibility.