Journal of Medical Entomology (2007) 44, 1067-1073

Carrie F. Nielsen and William K. Reisen (2007)
West Nile virus-infected dead corvids increase the risk of infection in Culex mosquitoes (Diptera: Culicidae) in domestic landscapes
Journal of Medical Entomology 44 (6), 1067-1073
Abstract: A comparative study of West Nile virus (family Flaviviridae, genus Flavivirus, WNV) infection rates in Culex mosquitoes collected at 13 sites, seven reporting WNV-positive dead corvids (case sites) and six without reported dead birds (control sites) was conducted in Davis, CA, from 14 to 21 July at the beginning of the 2006 WNV outbreak. In total, 3,051 Culex mosquitoes were collected using gravid traps and CO₂-baited traps; WNV-infected mosquitoes were only collected with CO₂-baited traps. WNV-infected Culex pipiens L. were collected at one of the seven case sites. Six of seven case sites yielded WNV-infected Culex tarsalis Coquillett, whereas only one of six control sites had WNV-infected Cx. tarsalis. Overall, the odds of finding WNV-positive mosquitoes were 19.75 times greater at sites reporting a WNV-infected dead corvid than sites without a WNV-infected dead corvid. Maximum likelihood estimates of the overall infection rates at the case sites were 3.48/1,000 for Cx. tarsalis and 8.69/1,000 for Cx. pipiens compared with 1.02/1,000 in Cx. tarsalis collected at the control sites. Results indicate that Cx. tarsalis was important in early season enzootic transmission within Davis and that sites reporting WNV-infected dead corvids are areas to focus control and surveillance efforts.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): William K. Reisen

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Culex tarsalis		U.S.A. (SW)
	Culex pipiens		U.S.A. (SW)