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Health Department





Learn how we track and control mosquitoes.  Get tips for preventing bites and reducing breeding areas.


In summer, we watch certain mosquito breeding areas for mosquitoes that carry diseases that can make you sick.



Why are we concerned about mosquitoes?

Mosquitoes can spread diseases like West Nile Virus.  The main mosquito species we track is the Culex mosquito.  This species can cause West Nile Virus infection in humans.


What do we do to reduce numbers of mosquitoes that cause disease?

In addition to watching breeding areas, we trap adult mosquitoes to measure how many are in an area.  Some of the mosquitoes are tested for West Nile Virus.  If we find high numbers of the species that can spread West Nile Virus, we treat water on public lands to reduce the number of mosquitoes.


You can prevent mosquito bites and disease


  • Wear long-sleeved shirts and long pants from dusk through dawn.  That is when many mosquitoes are most active.


  • Install or fix screens on windows and doors to keep mosquitoes outside.


  • Use EPA-registered insect repellents and follow instructions carefully.


  • Apply permethrin to your clothes and gear or buy items treated with permethrin.


Prevent Mosquito Bites


Get rid of areas where mosquitoes breed

Mosquitoes lay eggs in or near water.  Once a week, dump or clear water out of things like:


  • Flower pots
  • Gutters
  • Buckets
  • Pool covers
  • Pet water dishes
  • Birdbaths
  • Rain barrels
  • Trash cans


Get rid of areas where mosquitoes breed



Vectorborne Disease Toolkit







Health Department Office Location
2nd Floor, 300 4th St. N.
La Crosse, WI 54601

Main Business Phone: 608-785-9872
Main Fax: 608-785-9846
[email protected]
In a public health emergency call 911
WI Relay Service and Interpretation Services Available

Office Hours: 8:00am to 4:30pm Monday-Friday; some service hours may vary

Collaboratively promoting a healthful community for all people.