RESUMEN
INTRODUCTION: Chad is a country within the Lake Chad sub region, currently at risk for poliovirus infection. The Lake Chad Task Team on polio eradication in this sub region made significant efforts to reduce the risk of polio transmission in Chad by tacking immunization teams in the Island Settlement using a Geographic Information System (GIS) technology. This article demonstrates the application of GIS technology to track vaccination teams to monitor immunization coverage in the Island settlements, reduce the number of missed settlements, to provide evidence for vaccination implementation and accountability and improve team performance. METHODS: In each district where tracking was conducted, global positioning system-enabled Android phones were given to each team on a daily basis and were used to record team tracks. These tracks were uploaded to a dashboard to show the level of coverage and identify areas missed by the teams. RESULTS: In 2018, tracking covered 30 immunization days, in six rounds. Approximately average of 1173 Island settlements were tracked and covered in each of the six rounds. A total of 806,999 persons aged 0-10 years were immunized, out of which 4273 were zero dose cases at the point of their immunization. Tracking activities were conducted. There was an improvement in the geographic coverage of settlements and an overall reduction in the number of missed settlements. CONCLUSIONS: The tracking of vaccination teams and Island settlements ensured useful information for planning and implementation of polio campaigns and enabled supervisors to evaluate performance of vaccination teams.