Thibodaux Mosquito Pool Positive for West Nile Virus

This is to inform you that the Louisiana Animal Disease Diagnostic Laboratory has confirmed one of our mosquito samples positive for West Nile Encephalitis (WNV). Said sample was collected in the City Of Thibodaux area of Lafourche Parish (Zone L34) on September 18th. In accordance with the Expanded Transmission Protocol we are suggesting the following.

1) The location described will serve as the epicenter from which inspection, sampling, and control efforts will radiate.

2) Personnel will be assigned to inspect the immediate area surrounding the epicenter and to continue outward for an approximate five city block area depending upon the geographic location, the topography, and the surrounding conditions. The purpose of the search will be to locate vector mosquito (the Southern House Mosquito and/or the Asian Tiger) breeding sites. Once located, Mosquito Control will address the larvae with the feasible means necessary to control the situation.

3) Residents in the area will be made aware that there is a heightened potential for encephalitis infection in their neighborhood and that personal protection and yard sanitation is recommended. This will be done by distributing informative literature within an approximate five city block radius of the epicenter.

4) Gravid Traps will be used to sample the adult mosquito population in a five City block area radiating from the epicenter. The number of mosquitoes collected will serve to quantify the adult population and provide specimens for testing.

5) During the evening hours, truck mounted sprayers will be assigned to Spray Zone L34 in an effort to reduce/maintain the vector population below the critical level. Spraying will be conducted on the evenings of September 22nd, 23rd, and 24th weather permitting.

6) The efficacy of this operation will be determined through the use of Gravid Traps that are scheduled for operation following the spray efforts. The number of mosquitoes collected will serve to quantify the adult population and provide specimens to be submitted for testing in our laboratory. This will reduce turn-around time of results to one or two days. Elevated abatement operations will continue until vector mosquito numbers fall below established threshold levels.