Mapping Emerging Settlements: How Geospatial Data Helps Reach Missed Children
A vaccination team visits a settlement on their Master List, but there’s another settlement in the distance. What happens if the team doesn’t know that it exists?
Imagine you’re a child who is waiting to get vaccinated. You’re expecting someone, but are they expecting you? How many children might be missed in vaccination campaigns because they live in settlements that are not being tracked?
These are some questions addressed in a recent presentation by DevPartners Senior Consultant, spatial epidemiologist and data scientist Michelle Schmitz, at the Human Planet Forum 2025, a flagship event of the GEO Human Planet Initiative co-hosted by the European Commission’s Joint Research Centre in Ispra, Italy. This forum brought together scientists, policymakers, United Nations staff, civil society and the private sector to co-create actionable knowledge related to the human presence on earth using open geospatial data in various sectors, including disaster risk reduction, global sustainability and societal resilience.
In her presentation, Using Vaccination Campaign Data to Quantify Settlement Listings for a Polio Vaccination Campaign, Michelle demonstrated the power of using geospatial data to accelerate progress toward polio eradication by identifying settlements that were potentially not visited by vaccination campaigns. The presentation was based on the concept of an “emerging settlement” – a “missed” settlement which did not have any geolocated vaccination campaign activity recorded within its boundaries.
At a high level this approach overlays maps of settlements over GPS points and data from vaccination campaigns. By combining these, one is able to see where there might be blank spots – settlements with no recorded vaccination campaign visit. Teams can then take a closer look at the blank spots and update their vaccination plans.
Michelle, and her team at DevPartners, developed a point-in-polygon-based analytic methodology to identify these settlements, using various geolocated vaccination campaign datasets and GRID3 settlement extents, with the goal in assisting with vaccination campaign program microplanning in northern Nigeria across 6 vaccination campaigns between March and October 2025. Residential status of emerging settlements was analyzed for these settlements using OpenStreetMap, while counts of missed buildings and missed children were estimated using a zonal statistics procedure performed with these estimated settlements and GRID3’s gridded Nigerian population datasets.
Putting this list of emerging settlements in the hands of key stakeholders helps ensure their inclusion in microplanning for future campaign, which potentially increases the likelihood of these settlements being reached. The analysis was performed iteratively across the 6 campaigns. These results indicated that many of the emerging settlements, which were identified by the team, were visited within subsequent campaigns.
This analytic approach is one demonstration of how mapping settlement patterns and tracking immunization coverage in hard-to-reach areas can help to put potentially missed individuals and communities on the map. In combining satellite imagery and device-collected geospatial data, the power of Earth observation data can be brought to decision-makers, enabling more precise targeting of vaccination campaigns and public health interventions.
To learn more about how DevPartners empowers communities and decision-makers to leverage geospatial technology for good, please explore our ongoing projects and initiatives.
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