Assessment of the spatial accessibility to the rabies vaccination campaign in Bogotá, Colombia

Abstract

Introduction: The access of Bogota’s population to health services is unknown, and this hinders the planning of health prevention strategies. Objective: To estimate the spatial accessibility to the vaccination sites of the 2011 campaign against rabies in Bogotá, Colombia, and to compare its efficiency with two other spatial coverage methodologies. Materials and methods: Spatial accessibility was determined using the two-step floating catchment area model (2SFCA). We calculated spatial coverage by establishing circular buffer zones using Euclidean distances, and irregular zones around the vaccination sites using Dijkstra’s algorithm on the city’s street network. Results: The spatial coverage of the program was 78.4% using the circular buffer zones, and 60.2% using Dijsktra’s algorithm. The spatial accessibility analysis revealed that the periphery of the city had the lowest accessibility to the program. This peripheral area is a very critical zone because it is an urban-rural interface, which represents a risk for the re-introduction of rabies in the city. Conclusions: The 2SFCA spatial accessibility model is an effective tool to identify isolated areas, evaluate health services use more precisely, and provide basis for their strategic location. We concluded that this approach had the potential to improve resource efficiency when planning rabies control programs in urban environments such as Bogotá. The findings emphasize the need for surveillance and intervention in isolated areas with low access to services.