Larimer County spraying for West Nile mosquitoes in SE Fort Collins

The Larimer County Department of Health and Environment intends to spray a high-risk area of southeastern Fort Collins, including property in both the city and in unincorporated Larimer County, to reduce West Nile virus-infected mosquitoes. The spraying will take place on August 15 and 18, weather permitting, between sunset and midnight. (If weather prevents spraying on those days, the back-up dates are Monday Aug. 18 and 20).

The area to be sprayed is bordered by Harmony Road on the north, Carpenter on the south, Lemay, on the west and I-25 on the east.

The spraying is being done to reduce the level of mosquitoes carrying WNV infection in this area that currently has the highest level of infected mosquitoes in the city. For the past two weeks, this area has surpassed the threshold for which the Health Department recommends spraying.

“The area where the spraying will take place is not only is at high risk now, but it also had the highest rate of WNV disease in the city last year,” said Dr. Adrienne LeBailly, director of the Health Department. “The city’s criteria for their West Nile Management Program will not allow them to spray this area until multiple human cases are reported in the same week, but to be effective, spraying needs to occur when mosquito infection rates are high, not when case reports come in weeks later.”

The Larimer County Board of Health has approved this course of action and the County Commissioners have also indicated their support.

LeBailly expressed her appreciation to City of Fort Collins staff for assisting the department in notifying city residents about the dates and location the spraying is to occur. The Health Department will pay for this spraying out of the department’s public health emergency funds.

LeBailly stressed that both community actions and personal actions help to reduce the risk of West Nile infection. Measures that individuals and households can take include:

• Use a mosquito repellent that has been proven to be effective against West Nile Virus-carrying mosquitoes. Ones that contain DEET, Picaridin, Oil of Lemon Eucalyptus (with active ingredient PMD, or p-menthane diol) or IR3535 are good choices.
• Keep exposed skin covered or use a repellent when outdoors, especially between dusk and dawn or on cloudy days.
• Drain standing water in your yard or in your garden.
• Add mosquito-eating minnows to or a mosquito “dunk” to ornamental ponds that feature still water.
• Point a fan toward outdoor tables when eating out of doors to help blow away mosquitoes.
• Use netting over baby carriers and strollers
• Keep window screens repaired.

Information on the spraying will be available at The public may also call the West Nile information line at 970-498-6792.

To subscribe to County notification of spraying, go to and scroll down to West Nile virus.

Support Northern Colorado Journalism

Show your support for North Forty News by helping us produce more content. It's a kind and simple gesture that will help us continue to bring more content to you.

BONUS - Donors get a link in their receipt to sign up for our once-per-week instant text messaging alert. Get your e-copy of North Forty News the moment it is released!

Click to Donate