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West Nile Virus

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En esta página, usted encontrará consejos, recursos y boletines de publicación inmediata que le ayudara a mantenerse informado y protéjase.

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WNV Spraying Alerts#

Diagram of the 4 D's - Drain, Defend, Dress, and Dusk till Dawn

In the event that the City of Fort Collins decides to spray for mosquitoes, you can sign up for community alerts at NOCO Alert

Email or Phone Call Alerts: Create an account and under "My Alert Subscriptions" click "Community Alerts" and then check the "Fort Collins" box and check "West Nile Virus Spraying" to receive alerts.

Text Alerts: To receive a text message alert, simply text FCWNV to 888-777. 

NOCO Alert is managed by LETA911, which is the Governing Authority for 9-1-1 in Larimer County, Colorado. LETA911 provides oversight to 9-1-1, the equipment, and the programs funded by LETA. This includes non-emergency or community alerts for WNV adulticiding. 

Register for NOCO Alerts

Protect Yourself with the Four D's!#

Diagram of the 4 D's - Drain, Defend, Dress, and Dusk till Dawn
  1. Drain: Mosquitoes breed in water! Drain any standing water in your yard each week. Bird baths, clogged gutters, and kiddie pools are common breeding sites.
  2. Dress: Wear lightweight, long-sleeved shirts and long pants while outdoors. Spray clothing with insect repellent since mosquitoes may bite through clothing.
  3. Defend: Apply insect repellent sparingly to exposed skin. Use an approved repellent according to its label. Find the repellent that is right for you.
  4. Dawn/Dusk: Limit time spent outdoors at dusk through dawn, when mosquitoes are most active and feeding.

Learn More

Weekly Vector Index#

Recommendations to spray for adult mosquitoes are made by the Larimer County Health Department, and are based on data from at least a 5-trap area that has a vector index of 0.75 or higher. The City operates a network of 53 traps providing weekly data on the level of WNV in targeted areas.

WNV vector index levels updated weekly, June 15 through early September.

Last updated: September 8, 2020. Next scheduled update: June, 2021

VECTOR INDEX (map of quadrants):

NW Quadrant: 0.00   
NE Quadrant:  0.00    
SE Quadrant:  0.00   
SW Quadrant: 0.00 

Highest Vector Index value for 5-trap (minimum) Floating Zone: 0.00

Floating Zone description: NA

Map of Mosquito Traps

PLEASE NOTE: In order to best target infected mosquitoes, treatment zones are based on current data and are often different, smaller, or may cross quadrants. 

Mosquitoes don’t respect quadrant boundaries. Vector index values for quadrants are provided to help residents understand a consistent measure of risk throughout the season and over time.

While the vector index for an entire quadrant may be less than 0.75, it is very possible that areas of smaller or different geographical makeup exceed 0.75. Any area of 5 traps or more may become a treatment area regardless of how or where it fits into the quadrants.

When determining treatment areas, the goals are as follows:

  • Be effective, responsible, and judicious with pesticides
  • Target as small an area as possible
  • Target as early as is reasonable to limit viral amplification
  • Treatment areas must be at least 5 traps in size to be statistically valid

Interested in how the Vector Index is calculated? Find more information from the Centers of Disease Control here.


Most recent three week's trap data:

West Nile Virus Technical Advisory Committee#

West Nile Virus committee meeting and writing on white board

The West Nile Virus Technical Advisory Committee meets to discuss the previous mosquito season and considers recommendations for future response guidelines. The committee is composed of City-appointed experts who provide technical expertise and make recommendations to City Council regarding the City’s West Nile Virus Management Policy. Visit their webpage for meeting minutes and to get notifications when new minutes are available.

Upcoming Meetings:

  • 2020 - 2021 dates to be determined

Meetings are held from 4:30 - 6:00 PM in the Parks Department Conference Room, 413 S. Bryan Ave.

New Interactive Mosquito Surveillance & Control Map#

Map of mosquito surveillance and control

Our mosquito control contractor, Vector Disease Control International, has a NEW interactive mosquito surveillance and control map.

View Map

Businesses Can Apply To Opt Out Of Spraying#

Sign that says 'Organic Ranch Do Not Spray Pesiticides'

If you are a business or laboratory you can apply to opt out of our adulticiding (spraying operations). Please keep in mind only commercial businesses able to prove a long-term negative financial impact on their business will be considered. To apply, enter your business and contact information. Applicants will receive an application via email with the requirements and details of the opt-out.

Apply to Opt Out