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West Nile Virus Monitoring

West Nile virus Location Map in a New Window:  click here

Please Note:

Benton County Mosquito Control District (BCMC) routinely traps, identifies (species, population levels) and tests mosquitoes for the presence of West Nile virus (WNv).

If we have a confirmation of WNv (in-house testing of mosquitoes, reports from veterinarians or doctors, etc), the section (1 square mile) will be turned to a pink color.

  1) The colored sections may represent WNv positive mosquitoes, birds, horses and/or humans.

  2) BCMC attempts to collect from a representative area of the District, but we do not and cannot collect mosquitoes from all locations so a non-colored section does NOT necessarily mean that WNv is   not present.  We cannot trap everywhere in the District and both birds (carriers for WNv) and mosquitoes (transmitters of WNv) can be very mobile, so one should assume that infected mosquitoes could be in locations other than the colored sections.

  3) Once a section has been turned a color, it will stay so for the remainder of that season.

  4) The map is reset each January and may remain without colored sections for some time.  A "blank" map would be common through April, but after that a blank map does NOT necessarily mean their is not   any mosquito transmitted disease present, but rather, no such activity has been detected.


For more information on how the District performs its monitoring and testing of mosquitoes, please visit our testing page. The District only monitors and tests the mosquito population within the District, if you want information about humans, horses/other mammals, birds, and mosquitoes for the entire state, please click here.