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Mosquito Control Strategy

Update - July 23, 2024: West Nile Virus continues to spread and has been detected in Weld, Larimer and Boulder Counties, including within Longmont itself. Accordingly, the City of Longmont will continue adulticide spraying for mosquitoes. The following areas will be sprayed beginning at sunset this Thursday, July 25, 2024 and continuing through the evening or early morning, weather permitting.

  • Jim Hamm Nature Area (LM-03)
  • Sandstone Ranch (LM-22)
  • St Vrain Greenway at Emery (LM-28)
  • Creekside (LM-31)
  • Renaissance (LM-34)
  • Lanyon Park/Stoney Ridge (LM-41)
  • Rough and Ready South (LM-43)
  • Great Western Cattail Court (LM-44)

To learn more, read the full news release.

Background

Culex mosquitoes are the primary carriers of West Nile Virus, which they transfer to humans and other animals through bites. Weekly mosquito trapping typically begins in select Longmont neighborhoods in June and is based upon trapping history since 2003. This trapping activity looks for Culex mosquitoes that potentially could carry the West Nile Virus (WNV). No fogging or spraying is scheduled unless and until WNV-positive mosquitos are discovered in either Larimer, Boulder or Weld Counties and quantities in Longmont traps exceed 150 mosquitoes.

The City of Longmont contracts with VDCI to implement an Integrated Pest Management Program to combat mosquitoes that might carry the West Nile Virus. Visit the Integrated Pest Management Program webpage to find more information. The program focuses on first attacking mosquitoes in their larval stage before they become airborne. Known as larvicide, this is the best method since it eliminates mosquitoes before they hatch. This method also minimizes fogging or spraying to kill the adult, airborne bugs.

Trapping

View VDCI's trap reports and standard and enhanced spraying zones

These areas represent the standard and enhanced spray zones in Longmont:

  • The Shores  (LM-17)
  • Garden Acres Park (LM-10)
  • Lanyon Park/Stoney Ridge (LM-41)
  • Jim Hamm Nature Area (LM-03)
  • Union Reservoir (LM-23)
  • Rough & Ready South (LM-43)
  • Izaak Walton Park (LM-42)
  • Great Western Cattail Court (LM-44)
  • Sandstone Ranch (LM-22)
  • Creekside (LM-31)
  • Renaissance (LM-34)
  • St Vrain Greenway (LM-28) 
  • Enhanced Zones SW-2N & SW-2S
  • Enhanced Zone E-1E
  • Enhanced Zone E-3

These zones are evaluated annually (at a minimum) and adjusted as necessary. When local spraying is needed, it will be concentrated to these specific, predetermined zones. Spraying typically occurs on Thursday nights (weather permitting).

Citywide spraying is only conducted in cases of very large outbreaks and only after being directed by the county Health Department with input from the federal Centers for Disease Control (CDC).

Request Spray Notification or Shutoff

VDCI maintains a database of Longmont residents that have made notification or shutoff requests for their property if spraying is scheduled. There are three options:

  1. Call Notification Only - VDCI will phone you before spraying in your neighborhood
  2. Address Shut-off Only - VDCI will shut off the spray machine while driving past your property
  3. Notification & Shut-off - VDCI will phone you before spraying in your neighborhood and shut off the spray machine while driving past your property

Please contact VDCI to make a notification or shut-off request (online form available at the bottom of their webpage). To ensure that your request is properly received and processed in time, please use the online form rather than making a telephone call.


General Information on the West Nile Virus (WNV)

WNV is transmitted to humans from the bite of an infected female mosquito. While most infections are mild, the more serious infections can cause encephalitis (inflammation of the brain) and/or meningitis (inflammation of the brain's lining), loss of vision, paralysis, coma, tremors, convulsions, and death.

Symptoms of WNV include fever, extreme fatigue, headache, body aches, and occasionally can also include skin rashes and swollen lymph nodes. Generally, symptoms appear 3 to 14 days after being bitten by an infected mosquito. Anyone who experiences these symptoms should consult their health care providers. There is no treatment, cure, or human vaccination for the virus. Health care providers can only treat the symptoms to help patients feel better and possibly recover more quickly.

Generally, the mosquito season extends from late April until mid-October, with the end of the season usually signaled by the first hard freeze in the fall.

For more information about West Nile Virus, mosquito activity in Boulder County, or proactive steps to take, call the Colorado Health Information Line at 1-877-462-2911 or visit Boulder County's West Nile Virus webpage. To report nuisance mosquitoes, click on “Report Mosquito Activity” in the “What You Can Do” section on the website.


Practice the 4 D's of Prevention!

Protect yourself from West Nile Virus by following these tips during the summer.

  • Defend - Apply insect repellent sparingly to exposed skin. During the peak WNV season (mid-June through August), infected mosquitoes can be found all along the Front Range. Use repellent where you live, work and recreate.
  • Dress in lightweight long-sleeved shirts and long pants while outdoors. Mosquitoes can bite through clothing, so spray it with insect repellent.
  • Move indoors from Dusk until sunrise. If possible, avoid the outdoors during peak mosquito biting hours.
  • Drain standing water where mosquitoes can breed. Bird baths, clogged gutters and kiddie pools are common breeding sites.


Additional Resources

Hotline Numbers

  • Report problem areas in your neighborhood by calling VDCI at 303-428-5908.
  • State Department of Public Health and Environment's West Nile virus information hotline 303-692-2799
  • For information in Boulder County, contact the Boulder County Health Department at 303-441-1564 or communicable diseases at 303-413-7500

Websites, Videos and Other Resources