HomeMy WebLinkAboutMemo - Mail Packet - 8/8/2023 - Memorandum From Ryan Vincent And Amy Resseguie Re: West Nile Virus (Wnv) – Recommended Adult Mosquito Treatment 1745 Hoffman Mill Road
PO Box 580, Fort Collins, CO 80522-0580
MEMORANDUM
Date: August 1, 2023
To: Mayor and City Councilmembers
From: Ryan Vincent, Crew Chief, Natural Areas
Amy Resseguie, Lead Specialist, Communications & Public Involvement
Through: Kelly DiMartino, City Manager
Tyler Marr, Deputy City Manager
Dean Klingner, Director, Community Services
Mike Calhoon, Director, Parks
Katie Donahue, Director, Natural Areas
Subject: West Nile virus (WNV) – Recommended Adult Mosquito Treatment
Summary:
The Larimer County Department of Health and Environment (the County) is
recommending the City of Fort Collins spray for mosquitoes between Mulberry and
Carpenter, and Taft and College on Sunday, August 6. The recommended spray area
carries a vector index (VI) of 1.06, exceeding the policy threshold of 0.75, and conforms with the
City’s policies for mosquito spraying.
Current Vector Index:
Week No: 29 Vector Index
Threshold:
Previous Week Vector
Index:
Current Vector
Index:
FC – Zone NW NA 0.39 0.23
FC – Zone NE NA 1.23 0.68
FC – Zone SE NA 0.86 0.30
FC – Zone SW NA 0.79 1.013
FC – Citywide NA 0.86 0.51
Floating Zone 0.75 1.23 1.06
Current Conditions: Last week’s data showed 22 WNV-positive traps, while this week’s data
includes less, at 17 positive traps. Two key points highlight this week’s data: first, an increasing
VI trend continues in the southwest quadrant. The spray area recommended by the County will
address this area while also including parts of the northwest quadrant that contained WNV
positive traps. Second, a decreasing VI in other parts of the city is positive news.
Again this week, an additional and very significant consideration is the strain placed on regional
mosquito management services with the widespread WNV risk throughout the Northern
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City of Fort Collins
Colorado area. The recommendation from the County includes modifications accounting for the
limited resources. Therefore, the recommendation indicates a single night application. When all
traps in the recommended spray area are included, the VI for that area is 1.06, which exceeds
the policy threshold.
Process for Spray Recommendations: When the City’s trapping network shows WNV activity
beyond the threshold of 0.75, the Larimer County Department of Health and Environment
(LCDHE) makes a recommendation that the City conduct an application to treat adult
mosquitoes. When an application is recommended, areas of concern are identified based on
data from a minimum of 5 traps. Identified treatment areas may be sub-zone or may cross zone
boundaries.
Outreach and Public Awareness:
Phone, email, and text notifications will be issued on Tuesday to all individuals signed up to
receive such notifications through Larimer Emergency Telephone Authority. A press release will
be issued, and information will be shared through social media. Webpage content will be
updated with the latest vector index values and a map of the planned spray area. All key
communications are shared in English and Spanish.
Throughout the West Nile Virus season, general outreach and education information is centered
on “4Ds” messaging, which encourages people to Drain standing water, Dress in long pants and
sleeves to deter biting, Defend with EPA-approved repellant, and avoid the high mosquito
activity time between Dusk & Dawn. Messaging also encourages community members to opt-in
to receive notification about any future spray events.
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Current Week:Week Ending Date: 7/29/2023
2023 West Nile Virus Vector Index
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Drake Road Drake Road
0.00
0.10
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0.90
1.00
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NW Quadrant Vector Index vs. Historic (Red)
Current Vector Index Historic Vector Index 0.75 Vector Index Threshold
0.00
0.10
0.20
0.30
0.40
0.50
0.60
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0.80
0.90
1.00
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NE Quadrant Vector Index vs. Historic (Red)
Current Vector Index Historic Vector Index 0.75 Vector Index Threshold
0.00
0.10
0.20
0.30
0.40
0.50
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1.00
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SW Quadrant Vector Index vs. Historic (Red)
Current Vector Index Historic Vector Index 0.75 Vector Index Threshold
0.00
0.10
0.20
0.30
0.40
0.50
0.60
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0.90
1.00
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SE Quadrant Vector Index vs. Historic (Red)
Current Vector Index Historic Vector Index 0.75 Vector Index Threshold
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Sunday, Aug. 6, 2023 Sprayed Areas
CarpenterSpring Mesa
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