Using Geospatial Analysis to Target the Most Vulnerable Populations During the 2013 Flu Season

Background

Every year, the Los Angeles County Department of Public Health’s Community Health Services Program plans outreaches throughout the 8 Service Planning Areas to immunize individuals against the flu.  Historically, these outreach sites have been selected based on community agency requests and previous partnerships.  Although many of our communities in Los Angeles County are underserved, there may be groups of people that are more vulnerable to the effects of the flu that these outreaches may not be reaching out to.  This year, 4 vulnerable groups were targeted for flu outreaches: children, seniors, immunocompromised individuals, and the homeless.

Methods

Community Health Services Administration (CHSA) used GIS technology to spatially analyze flu outreach sites for two of the four groups: children and seniors.  Using 2010 Census Bureau census tract data, CHSA conducted a hot spot analysis to identify statistically significant clusters of children and seniors in order to determine what percentage of sites were within or at close proximity to these hot spots.

Results

Based on hot spot analysis, CHSA found that 88% of flu outreach sites were within or at close proximity to statistically significant clusters of children (91%) and seniors (85%).

Conclusion

GIS technology can be used as an evidence-based tool to improve health care practices and more effectively plan community interventions, including future flu outreaches, by allocating resources to areas of greatest need.  In addition, GIS maps can be used as an effective teaching tool to educate community stakeholders and increase awareness of specific issues affecting their communities.