A GIS Tool To Estimate West Nile Virus Risk based On A Degree-Day Model

Authors: ZOU, LI - UNIVERSITY OF WYOMING; MILLER, SCOTT - UNIVERESITY OF WYOMING; Schmidtmann, Edward

Submitted to: Environmental Monitoring and Assessment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/2006
Publication Date: 11/15/2006
Citation: Zou, L., Miller, S.N., Schmidtmann, E.T. 2006. A GIS tool to estimate west nile virus risk based on a degree-day model. Environmental Monitoring and Assessment.

Interpretive Summary: A computer software program was developed that will help in estimating West Nile virus activity. West Nile virus is a disease that is transmitted by blood feeding insects. It is possible to predict West Nile virus activity based on the insect vector populations. Mosquito development is largely dependent on temperatures and the software program use temperature information to predict mosquito populations and subsequently West Nile virus activity.

Technical Abstract: West Nile virus(Flaviviridae: Flavivirus) is a serious infectious disease that recently spread across the North America continent. A spatial analysis tool was developed on the ARCMap 9.x platform to estimate potential West Nile virus activitiy using a spatially explicit degree-day model. The mdoel identifies when the virus Extrinsic Incubartion Period (EIP) is completed within the vector longevitiy during mid-summer months. The EIP is treated as a threshold indicator of the potential for virus emergence and activity. Comparing the number of West Nile virus cases in Wyoming reported from 2003-2005 with model results, actual cases and predicted events of West Nile virus activity match relatively well. The model represnts a useful method for estimating potential West Nile virus activity in a large spatial scale.