HomeMy WebLinkAboutMemo - Read Before Packet - 8/22/2023 - Memorandum From Matt Parker 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 22, 2023
To: Mayor and City Councilmembers
From: Matt Parker, Sr. Supervisor, Natural Areas
Amy Resseguie, Lead Specialist, Communication
Through: Kelly DiMartino, City Manager
Tyler Marr, Deputy City Manager
Dean Klingner, Director, Community Services
Mike Calhoon, Director, Parks
Subject: West Nile virus (WNV) – Recommended Adult Mosquito Treatment
Summary:
The Larimer County Department of Health and Environment is recommending the City of
Fort Collins spray for mosquitoes in an area west of College Avenue, to Taft Hill Road,
south of Horsetooth Road, to Spring Mesa Road and Carpenter Road, on Sunday, August
27. The recommended spray area carries a vector index of 1.13, exceeding the policy threshold
of 0.75, and conforms with the City’s policies for mosquito spraying.
Current Vector Index:
Week No: 33 Vector Index
Threshold:
Previous Week Vector
Index:
Current Vector
Index:
FC – Zone NW NA 0.53 0.28
FC – Zone NE NA 0.42 0.73
FC – Zone SE NA 0.43 0.08
FC – Zone SW NA 0.27 0.74
FC – Citywide NA 0.45 0.41
Floating Zone 0.75 0.82 1.13
Current Conditions: Previous treatment applications have seemingly contributed to drastically
decreased abundance values. After the early season marked by tremendous mosquito
populations, numbers are largely near historic averages except in the SW quadrant. Infection
rates remain higher than historic averages except in the most recently treated area, the SE.
With a Vector Index of 0.74, the SW quadrant is the most active area this week. The floating
treatment zone is a targeted area within the SW quadrant. It is also important to note the
irrelevant data coming from the NE as the data does not reflect this past Sunday’s treatment
impact.
DocuSign Envelope ID: A6AD1E71-CF11-4419-AAE6-BF9B016FE722
City of Fort Collins
This week’s data indicates 12 WNV-positive traps, down from 16 last week, and 21 the week
before. Treatments continue to realize the intended impacts, found in the form of both
decreases in abundance and infection rates. The most recent example is the low vector index in
the SE, with both abundance and infection rate well below the historic average, and significantly
decreased from the previous 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
(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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DocuSign Envelope ID: A6AD1E71-CF11-4419-AAE6-BF9B016FE722
Sunday, Aug. 27, 2023 Sprayed Areas
CarpenterSpring Mesa
DocuSign Envelope ID: A6AD1E71-CF11-4419-AAE6-BF9B016FE722
33College AveCurrent Week:Week Ending Date: 8/20/20232023 West Nile Virus - Mean Culex (Female) Abundance per Trap NightCollege AveDrake RoadDrake Road0.020.040.060.080.0100.0120.0140.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37NE Quadrant Abundance vs Historic (Red)Current AbundanceHistoric Abundance0.020.040.060.080.0100.0120.0140.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37SW Quadrant Abundance vs Historic (Red)Current AbundanceHistoric Abundance0.020.040.060.080.0100.0120.0140.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37SE Quadrant Abundance vs Historic (Red)Current Vector AbundanceHistoric Vector Abundance0.020.040.060.080.0100.0120.0140.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37NW Quadrant Abundance vs Historic (Red)Current AbundanceHistoric AbundanceDocuSign Envelope ID: A6AD1E71-CF11-4419-AAE6-BF9B016FE722
33College AveCurrent Week:Week Ending Date: 8/20/20232023 West Nile Virus Vector IndexCollege AveDrake RoadDrake Road0.000.100.200.300.400.500.600.700.800.901.00Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37NW Quadrant Vector Index vs. Historic (Red)Current Vector IndexHistoric Vector Index0.75 Vector Index Threshold0.000.100.200.300.400.500.600.700.800.901.00Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37NE Quadrant Vector Index vs. Historic (Red)Current Vector IndexHistoric Vector Index0.75 Vector Index Threshold0.000.100.200.300.400.500.600.700.800.901.00Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37SW Quadrant Vector Index vs. Historic (Red)Current Vector IndexHistoric Vector Index0.75 Vector Index Threshold0.000.100.200.300.400.500.600.700.800.901.00Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37SE Quadrant Vector Index vs. Historic (Red)Current Vector IndexHistoric Vector Index0.75 Vector Index ThresholdDocuSign Envelope ID: A6AD1E71-CF11-4419-AAE6-BF9B016FE722
33College AveCurrent Week:Week Ending Date: 8/20/20232023 West Nile Virus Infection Rate per 1,000 (All Culex)College AveDrake RoadDrake Road0.05.010.015.020.025.030.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37NE Quadrant Infection Rate vs. Historic (Red)0.05.010.015.020.025.030.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37SW Quadrant Infection Rate vs. Historic (Red)0.05.010.015.020.025.030.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37SE Quadrant Infection Rate vs. Historic (Red)0.05.010.015.020.025.030.0Week24Week25Week26Week27Week28Week29Week30Week31Week32Week33Week34Week35Week36Week37NW Quadrant Infection Rate vs. Historic (Red)DocuSign Envelope ID: A6AD1E71-CF11-4419-AAE6-BF9B016FE722