Table 1.

Description of data sources and data collected

Source	Data collected
Telephone interview	• Demographics • Behaviors that might affect exposure to mosquitoes such as outdoor activities and working or attending school outside the home
Household visit	• Household mosquito prevention measures such as door and window screens • Potential mosquito larval habitats in the yard such as water-holding containers* • Potential mosquito larval habitats ≤ 100 m from residence such as flood irrigation and catch basins†
County databases	• Year of house construction • Neglected pools that are capable of serving as mosquito larval habitats located ≤ 500 m from residence as reported to county environmental services, May–June, 2010
Irrigation maps	• Irrigation service areas (water districts) and open irrigation canals ≤ 500 m from residence
Geographic Information System (GIS)	• Green space ≤ 500 m from residence such as parks, golf courses, and agricultural land • 2009 demographic information within census block groups such as population density and percent of houses that were vacant

^*Includes common yard containers and discarded artificial containers such as pots, inflatable pools, and tires.

^†Catch basins are defined as man-made depressions in the ground where storm water from roadways and/or residential areas is directed. Large fences or other barriers occasionally limited the visibility of all areas within 100 m of a residence.