HomeMy WebLinkAboutMemo - Mail Packet - 9/12/2023 - Memorandum From Ryan Vincent And Amy Resseguie Re: West Nile Virus (Wnv) – County Not Recommending Adult Mosquito Treatment 1745 Hoffman Mill Road
PO Box 580, Fort Collins, CO 80522-0580
MEMORANDUM
Date: September 5, 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
Matt Parker, Sr. Supervisor, Natural Areas
Subject: West Nile virus (WNV) – County Not Recommending Adult Mosquito Treatment
Summary:
The Larimer County Department of Health and Environment (the County) is not
recommending the City of Fort Collins spray for adult mosquitoes at this time. While
positive detections of WNV remain, there is not a floating zone with a vector index higher than
the 0.75 threshold.
Current Vector Index:
Week No: 34 Vector Index
Threshold:
Previous Week Vector
Index:
Current Vector
Index:
FC – Zone NW NA 0.28 0.04
FC – Zone NE NA 0.29 0.25
FC – Zone SE NA 0.40 0.18
FC – Zone SW NA 0.44 0.03
FC – Citywide NA 0.35 0.15
Floating Zone 0.75 0.73 0.25
Current Conditions: This week’s data shows 9 WNV-positive traps; down from 18 last week.
Both culex abundance and infection rates (the two factors producing the vector index) are near
a historically normal range, and we will not treat for adult mosquitoes this week.
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
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City of Fort Collins
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:
WNV-related social media posts will focus on the ongoing risk of WNV, reminding people to
mitigate breeding sites, practice self -protective measures, and sign up tor notifications through
LETA.
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: 9/2/2023
2023 West Nile Virus Vector Index
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Drake Road Drake Road
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
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
0.70
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
0.60
0.70
0.80
0.90
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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