Appropriate tools and methods for tropical microepidemiology: a case-study of malaria clustering in Ethiopia

Abstract

Background: The importance of local variations in patterns of health and disease are increasingly recognised, but, particularly in the case of tropical infections, available methods and resources for characterising disease clusters in time and space are limited. Whilst the Global Positioning System (GPS) allows accurate and easy determination of latitude and longitude, sophisticated Geographical Information Systems (GIS) that can process the data may not be available and accessible where they are most needed. Objective: To describe an appropriate procedure for interpreting GPS information. Methods: An example of space-time clustering of malaria cases around a dam in Ethiopia (106 cases in 129.7 child-years-at-risk) is used to demonstrate that GPS data can be interpreted simply and cheaply in under-resourced health service settings to provide timely and appropriate epidemiological assessments. Results: Malaria cases were clustered in time and space in the area surrounding a microdam. Conclusion: Quickly identifying disease foci using appropriate procedures in this manner could lead to better informed control and treatment activities which would represent a better use of resources as well as improved health for the community. [Ethiop.J.Health Dev. 2003;17(1):1-8]