Determination of true patient origin through motorcycle mapping: design and implementation of a community-defined geographic infrastructure surveillance tool in rural Sierra Leone.

Background: Village-level geographic infrastructure data are often insufficient in low-resource settings, despite accurate patient origin determination being essential for surveillance and outbreak management. We detail a novel and seemingly reliable method for the determination of true patient origin with proof of concept in rural Sierra Leone.

Methods: Potential villages (n=2263), identified within a 7800 km2 hospital catchment area from satellite imagery, were accessed by motorcycle and surveyed in person, capturing village name and community-defined section/chiefdom/district.

Results: A survey established 1740 inhabited villages and a village of origin determination tool (gazetteer) was produced. Recording the district/chiefdom/section/village at hospital registration allowed Global Positioning System patient origin determination in 2277/2344 (97.1%) attendances.

Conclusions: Our proof of concept reports a substantial and sustained record of true patient origin in a low-resource setting.