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Mosquito Spraying Has Ended for 2019

Mosquito spraying in Longmont has ended for the 2019 season. Thursday, Sept. 12, was the last date that spraying was conducted.
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This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.

Mosquito spraying in Longmont has ended for the 2019 season. Thursday, Sept. 12, was the last date that spraying was conducted.

The City of Longmont worked with mosquito control contractor Vector Disease Control International (VCDI) to combat mosquitoes that might carry the West Nile Virus (WNV). The City’s mosquito control strategy focused on mosquito disease control and not nuisance mosquitoes, first attacking mosquitoes in their larval stage before they became airborne, followed by fogging, or spraying, areas with high levels of adult mosquitoes.

WNV is transmitted to humans from the bite of an infected female mosquito. While most infections are mild, the more serious infections can cause serious illness or even death. 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.

“Eliminating mosquitoes before they hatch is the best way to fight the spread of the West Nile Virus,” said Dan Wolford, City of Longmont Land Program Administrator. Wolford manages the West Nile Program for Longmont. “Attacking mosquitoes in their larval stage is one of the City's integrated pest management strategies that eventually minimizes the amount of fogging needed later for airborne, adult mosquitoes.”

The City’s mosquito control strategy uses 12 “hotspot zones” that were identified based on historical data. Beginning in the spring, VCDI conducted Citywide larval inspections as well as weekly trapping in those hotspots and reported the results to the City.

There were two triggers for beginning fogging (more commonly called spraying): trapped mosquito numbers higher than
150, up from 100 in 2018, in a particular hotspot and the identification of WNV-positive mosquitoes anywhere in the three-county area made up of Boulder, Weld and Larimer.

WNV-positive mosquitoes were identified in Larimer County in late July, which led to spraying in Longmont beginning Aug. 1. Spraying took place weekly on Thursday nights through mid-September.

In Colorado this year, 114 mosquito pools tested positive for WNV (84% in the City's three-county region) and 27 human cases were reported this year across the state, according to Boulder County Public Health.

The City of Longmont spent approximately $88,375 to administer its mosquito control strategy in 2019.

Although the risk of being infected with West Nile Virus has abated for 2019, Boulder County Public Health and Longmont officials still encourage residents to take necessary precautions to
protect themselves. Keep safe and remember the 4Ds:

  1. Use DEET-enhanced insect repellent or alternative.
  2. DRESS in long sleeves and pants.
  3. Avoid the outdoors from DUSK until DAWN.
  4. DRAIN standing water outside your home.

To learn more about the City of Longmont’s mosquito control strategy, visit LongmontColorado.gov/westnile or call 303-651-8416.

For more information about the health impacts of WNS or mosquito activity in Boulder County, visit the Boulder County West Nile Virus webpage or call the Colorado Health Information Line at 1-877-462-2911.