Idaho's pertussis rates are some of the nation's highest despite immunization rate increases. A pertussis vaccine effectiveness study of Idaho children 6 to 59 months started July, 1998 and will be completed by December, 2000. Information is collected in a telephone interview with case parents and five age- and location-matched control families. Other studies have shown associations between demographic features, under-immunization, and disease. Idaho pertussis case demographics extracted from the vaccine study were examined using a GIS to investigate spatial relationships between high-risk areas and pertussis infection.
To analyze factors related to under-immunization, geographic and U.S. Census TIGER data were overlain with childhood immunization rates using ArcView 3.0. Preliminary analysis of approximately half the projected 40 cases and 200 controls indicates cases are less likely to receive their full pertussis immunization series (p=0.000), and the child's mother is less likely to have completed high school (p=0.006). Children who were not up-to-date on their pertussis immunizations were more likely to live in large households (p=0.004), have no insurance (p=0.002), or be on Medicaid (p=0.037). Family income level, race, and daycare usage were not significant factors.
GIS maps are useful for identifying geographic areas most in need of immunization intervention strategies. Locations of Idaho children with low immunization rates and areas with a large proportion of individuals possessing high-risk characteristics were mapped. Children in these at-risk areas can be targeted for more rigorous immunization intervention programs.
Learning Objectives: Understand the usefulness of Geographic Information Systems for immunization planning
Keywords: Geographic Information Systems, Immunizations
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.