Volume 14, Number 5—May 2008
Research
Efficacy of Aerial Spraying of Mosquito Adulticide in Reducing Incidence of West Nile Virus, California, 2005
, Stan Husted*, Cynthia Jean*, Carol Glaser*, and Vicki Kramer†Table 1
Number of human cases of infection with West Nile virus by location and temporal classification, California, 2005*
| Area† | Total | Pretreatment‡ | Posttreatment§ | Postincubation¶ | Population# |
|---|---|---|---|---|---|
| Treated, northern | 34 | 28 | 6 | 0 | 221,828 |
| Treated, southern | 21 | 20 | 1 | 0 | 338,579 |
| Buffer, northern | 13 | 9 | 4 | 3 | 94,399 |
| Buffer, southern | 8 | 5 | 3 | 1 | 50,127 |
| Untreated | 76 | 41 | 35 | 18 | 518,566 |
| Sacramento County | 152 | 103 | 49 | 22 | 1,223,499 |
| California | 670 | 357 | 313 | 197 | 32,648,149 |
*Only cases with known date of onset of illness and location information (i.e., Sacramento County at the address level and California at the county level) are included in the analysis.
†California excluding Sacramento County.
‡Refers to cases with onset of illness up to and including the last date that aerial adulticiding was conducted (ending 22 Aug for the southern treated area and southern buffer zone and 10 Aug for all other areas).
§Refers to cases with onset of illness after the last date that aerial adulticiding was conducted (beginning 23 Aug for the southern treated area and southern buffer zone and 11 Aug for all other areas).
¶Refers to cases with onset of illness >14 days after the first date that aerial adulticiding was conducted (beginning 4 Sep for the southern treated area and southern buffer zone and 23 Aug for all other areas).
#Population data source: UA Census 2000 TIGER/Line data made available in shapefile format through Environmental Systems Research Institute, Inc. (Redlands, CA, USA) (20).
