Development and Evaluation of GIS-Based Chlamydia Trachomatis Intervention Policy in Illinois.

Chlamydia trachomatis is the most prevalent infectious disease in the United States. Complications include pelvic inflammatory disease (PID), ectopic pregnancy, and infertility. The cost of PID in 1998 was estimated at greater than $1.9 billion. Screening intervention strategies are often consumed by those at low risk. The objective of this study is the development of a more cost-effective intervention strategy by employing Geographic Information Systems and Census Bureau demographic data in selected Local Health Departments in Illinois. Case studies of intervention activities at the state and local level were performed. An evaluability assessment model of current inputs, processes and outcomes was created. A proposed model utilizing additional state inputs was developed and tested. Interventions were evaluated for effectiveness in reducing the incidence of Chlamydia trachomatis. Societal cost effectiveness analysis was also performed. The proposed model was tested in 2006. Results indicate that only minimal changes in annual incidence are required for GIS-augmented interventions to be cost-effective.