American Journal of Epidemiology Advance Access originally published online on August 9, 2007
American Journal of Epidemiology 2007 166(9):1088-1095; doi:10.1093/aje/kwm184
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
ORIGINAL CONTRIBUTIONS |
Relating Diarrheal Disease to Social Networks and the Geographic Configuration of Communities in Rural Ecuador
1 School of Public Health, University of California, Berkeley, CA
2 Trinity College, Hartford, CT
3 Universidad San Francisco de Quito, Quito, Ecuador
4 Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI
Correspondence to Dr. Joseph N. S. Eisenberg, Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI 48104 (e-mail: jnse{at}umich.edu).
Received for publication December 21, 2006. Accepted for publication May 22, 2007.
Social networks and geographic structures of communities are important predictors of infectious disease transmission. To examine their joint effects on diarrheal disease and how these effects might develop, the authors analyzed social network and geographic data from northern coastal Ecuador and examined associations with diarrhea prevalence. Between July 2003 and May 2005, 113 cases of diarrhea were identified in nine communities. Concurrently, sociometric surveys were conducted, and households were mapped with geographic information systems. Spatial distribution metrics of households within communities and of communities with respect to roads were developed that predict social network degree in casual contact ("contact") and food-sharing ("food") networks. The mean degree is 25–40% lower in communities with versus without road access and 66–94% lower in communities with lowest versus highest housing density. Associations with diarrheal disease were found for housing density (comparing dense with dispersed communities: risk ratio = 3.3, 95% confidence interval (CI): 1.1, 10.0) and social connectedness (comparing lowest with highest degree communities: risk ratio = 3.4, 95% CI: 1.1, 10.1 in the contact network and risk ratio = 4.9, 95% CI: 1.1, 21.9 in the food network). Some of these differences may be related to more new residents, lower housing density, and less social connectedness in road communities.
diarrhea; Ecuador; environment and public health; geography; social support
Abbreviations: CI, confidence interval