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Abstract & Introduction

Background

Materials & Methods

Results & Discussion

References

Appendices

ABSTRACT

In the Fall of 2002, the Indiana University Southeast Ecology class and the Floyd and Clark County Health Departments initiated a West Nile Virus mosquito surveillance program. Mosquitoes were taken using CDC approved collection devices provided by the health departments. Seventeen locations were sampled in Clark County and twelve in Floyd County. Results indicated positive mosquito pools at five locations in Floyd County and three locations in Clark County. We recommend that the monitoring program be continued in the Spring of 2003 to determine the successional progression of the virus in the various mosquito pools. Additionally, we suggest that the counties seek funds for two student interns to work on mosquito monitoring and other health-related concerns. Finally, because of the possibility of the introduction of other infectious agents into our region, we recommend that Indiana University Southeast immediately pursue the possibility of offering a Master of Public Health degree. Other avenues of possible research and academic endeavors discussed with the respective health departments are summarized in this report.

INTRODUCTION

West Nile virus (WNV) was first reported in the United States in New York City in 1999. Since then, the virus rapidly expanded into nearly all states including Indiana.  Following the finding of WNV in Indiana in 2001 and dead infected birds in Clark and Floyd Counties, Indiana University Southeast and the Clark and Floyd County Health Departments initiated a West Nile virus mosquito surveillance program in the fall of 2002.  The fall Ecology class was responsible for the collection, sorting, identification and processing of the mosquitoes for analysis at the Indiana State Department of Health laboratories.  The results of this study were presented to Clark and Floyd County Health Departments and have been published on the web. This surveillance resumed in June 2003, expanding to include the townships in Harrison County. The purpose of this report is to present a summary and analysis of our 2003 findings.
Our monitoring program is part of a nationwide surveillance effort (1,2).  ArboNet is the national electronic surveillance system established by the CDC to assist states in tracking West Nile virus and other mosquito-borne diseases. The Centers for Disease Control and Prevention are working with the U.S. Geological Survey, U.S. Department of Agriculture Animal and Plant Health Inspection Service, state wildlife agencies, and state and local health and vector control agencies to track the occurrence of West Nile virus. The information for positive mosquito pools on the state and CDC maps was generated during this project.
For the 2002 mosquito surveillance, mosquitoes were collected, identified and express mailed to the State Department of Health for analysis.  We often waited for several weeks for the results.  Obviously, any virus positive mosquitoes in a particular area would have already had blood meals and infected other birds, horses and humans.
To eliminate and reduce human exposure to West Nile virus, sites with positive mosquitoes should be located and treated immediately.  A new test, the VecTest, is designed for rapid detection. The VecTest, a West Nile virus/Saint Louis Encephalitis antigen panel assay, is a rapid detection dipstick test for both West Nile virus and St. Louis encephalitis.  Test results are available in 15 minutes allowing for immediate abatement measures to be implemented.
In May 2003, Dr. Claude Baker and Ms. August Nelson were trained and certified by Indiana University in the use of the VecTest in an effort to better assist the local health departments in their battle against the West Nile Virus (Appendix I).