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West Nile Virus

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City & County to Spray to Reduce West Nile Virus Risk

The City of Fort Collins and Larimer County Health Department will spray for mosquitoes on the north eastern part of Fort Collins and adjacent Larimer County on the evening Sunday, August 28.

Map of Spray Areas | Track Spraying Trucks | View Press Release

El Departamento De Salud Del Condado De Larimer Rociará Picaduras

El Departamento de Salud del Condado de Larimer rociará picaduras para prevenir del virus Nilo Occidental. Para más información:

El Mapa de los Áreas

West Nile Virus Risk Map

View the West Nile Virus Risk Map to understand where testing indicates the presence of West Nile virus positive mosquitoes. The City of Fort Collins operates 53 traps throughout the community to provide up to date information on the severity of West Nile virus.

Weekly Vector Index

Updated weekly during the summer active breeding season

The City of Fort Collins has four separate zones for adulticiding (spraying). Before any spraying is considered, the vector index must be 0.75 in a zone and there must be more than one human case of West Nile in a week.

Zone NW = 0.106
Zone NE = 0.097
Zone SE = 0.190
Zone SW = 0.000
Week 34 Charts

Weekly trapping and testing began the week of June 13, 2016 (Week 24)

Human Cases

Total number of human cases in Fort Collins for the 2016 season as of August 17, 2016: 4

West Nile Virus Poll

As a data driven organization the City of Fort Collins is gathering information from the community about the level of awareness of West Nile Virus. Please take a moment to fill out the following poll in order to help use provide the community with better information on this disease. 
Take the WNV Awareness Poll 

Protect Yourself with the Four D's!

Spotlight image: Protect Yourself with the Four D's!

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.

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. 

Find out more!

Businesses Can Apply to Opt Out of Spraying

Spotlight image: Businesses Can Apply to Opt Out of Spraying

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 to 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 here.

New Interactive Mosquito Surveillance & Control Map

Spotlight image: New Interactive Mosquito Surveillance & Control Map

Our mosquito contractor, Colorado Mosquito Control, has a NEW interactive mosquito surveillance and control map.

¿Habla Español?

Spotlight image:  ¿Habla Español?

Protéjase de picaduras de mosquitos y del virus Nilo Occidental este verano. En esta página, usted encontrará consejos, recursos y boletines de publicación inmediata que le ayudara a mantenerse informado.


West Nile Notify: Subscribe to Receive Spraying Notifications

Spotlight image: West Nile Notify: Subscribe to Receive Spraying Notifications

The City of Fort Collins developed a system, West Nile Notify, to send out emails in advance of our spraying operations. Simply subscribe by adding your email to our list. West Nile Notify allows citizens to be notified as early as possible to scheduled mosquito adulticiding. This service is free of charge and subscribers can choose to receive notifications on any or all of the six spraying areas. If you do not have an email address, please call the Colorado Mosquito Control at 970-962-2582.

West Nile Virus Technical Advisory Committee

Spotlight image: West Nile Virus Technical Advisory Committee

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.

LETA WNV Community Alerts

Spotlight image: LETA WNV Community Alerts

Take a moment to sign up for community alerts for West Nile virus (WNV) spraying at Larimer Emergency Telephone Authority (LETA911). 

LETA911, 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. 

Create an account and under "My Alert Subscriptions" click "Community Alerts" and then check the "Fort Collins | Poudre Fire Authority" box and check "West Nile Virus Spraying" to receive alerts.