HomeMy WebLinkAboutMemo - Mail Packet - 8/11/2020 - Memorandum From Matt Parker, Amy Resseguie, Tyler Marr Re: West Nile Virus (Wnv) Update
City Manager’s Office
PO Box 580
300 LaPorte Ave.
Fort Collins, CO 80522
970.221.6505
970.224.6107 - fax
fcgov.com
MEMORANDUM
Date: August 6, 2020
To: Mayor and City Councilmembers
From: Matt Parker, Supervisor, Natural Areas
Amy Resseguie, Sr. Specialist, Communications
Tyler Marr, Interim Director, Information & Employee Services
Through: Darin Atteberry, City Manager
Kelly DiMartino, Deputy City Manager
John Stokes, Interim Director, Community Services
Mike Calhoon, Director, Parks
Zoe Shark, Interim Director, Natural Areas
Mark Sears, Manager, Natural Areas
Re: West Nile virus (WNV) Update
Summary:
This week’s data shows WNV activity remains below the historic average and well below the
City’s policy threshold for adult mosquito treatments. WNV management actions are in full
swing with larval treatments, trapping, and testing; however, public outreach efforts are
reduced due to social gathering restrictions and budget reductions. Although both mosquito
abundance and infection rate are below historic averages, the next 6 weeks of the season
allows for ample time for the vector index to rise significantly.
Current Vector Index:
Week No: 31 Vector Index
Threshold:
Previous Week
Vector Index:
Current Vector
Index:
FC – Zone NW NA 0.00 0.00
FC – Zone NE NA 0.00 0.00
FC – Zone SE NA 0.07 0.02
FC – Zone SW NA 0.00 0.00
FC – Citywide NA 0.02 0.01
Floating Zone 0.75 0.20 0.08
Current Conditions: Last week’s single positive sample and this week’s single positive sample came out
of the SE quadrant of the city; last week’s at the corner of Carpenter Road and South Timberline Road,
and this week’s in the area bounded by Horsetooth Rd., Zeigler Rd., Harmony Rd., and S. Timberline
Rd. A floating zone consisting of the nearest 5 traps indicates a vector index value of 0.08. For
reference, weeks 30 and 31 produced two positive samples each in 2019.
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With recent localized rain events recording upwards of 0.5” it is likely that mosquito reproduction will
increase. However, with the return of 90+ degree days toward the end of this week and next, the
general trend of hot and dry conditions is likely to continue to bring lower-than-average mosquito
abundance. Accelerated amplification cycle due to bird (the WNV host/reservoir) congregation around
limited water supplies remains the major concern.
Process for Spray Recommendations: Current WNV conditions are well under the 0.75 threshold for
adult mosquito spraying applications. If the City’s trapping network shows WNV activity beyond the
vector index threshold of 0.75, the Larimer County Health Department typically makes a treatment
recommendation to the City. If an application is recommended, areas of concern will be 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:
Outreach and education efforts are underway and will increase in community visibility through the
month of August. Information was distributed earlier this summer via City newsletters, social media, and
a utility bill insert. Digital, print and radio advertising; street banners; bus bench ads; and additional
social media content began August 1 and will run through the end of August. Due to COVID-19
gathering restrictions and anticipated budget reductions, some outreach methods-such as staffing at
events, or poster displays inside restaurants-are not available this year. To maximize the outreach
budget, the digital, print and radio advertising window been shortened slightly from previous years in
order to focus the largest advertising reach at the peak of the West Nile season (August). In the event
of a localized spike in the vector index value, door hangers will also be distributed. Outreach materials
and messaging are shared in both English and Spanish.
Outreach 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. Please see example below.
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DocuSign Envelope ID: 22222F0F-7EEE-45C4-8C03-89B930F7E96A