2018-179 2018 Mosquito SeasonDecember 14, 2018 2018-179
INFORMAL STAFF REPORT
TO MAYOR AND CITY COUNCIL
SUBJECT:
Provide notification of the end of the 2018 mosquito season.
DISCUSSION:
Based on mosquito trap results from the last several weeks, low temperature ranges, and results of
the West Nile virus (WNV) screening by the Texas Department of State Health Services and the
University of North Texas (UNT), Denton staff members consider the 2018 mosquito season to be
completed. In accordance with the City of Denton’s Mosquito Surveillance and Response Plan
(MSRP), the West Nile Virus risk level will be reset to Risk Level two, and will remain at that
level until the start of the 2019 mosquito season. The following information is provided as a brief
summary of the 2018 season:
Trapping began on May 1 and ended on November 25.
Approximately 532 traps deployed for routine monitoring (samples sent to the TDSHS for
WNV testing and mosquito species identification)
Approximately 248 traps deployed for local testing for WNV (conducted by UNT)
Approximately 2,704 larvicide applications by the Drainage department
92 larvicide treatments distributed to citizens
Two traps tested positive for WNV. The earliest detection was on September 24, and the
latest detection was October 29.
No reported cases of human WNV within the City of Denton
No California Serogroup viruses were detected in the City of Denton
No reported cases of human Zika within the City of Denton
The 2018 season was a second consecutive mild season with a late onset at the end of September.
A very similar pattern observed in 2017. The sampling of mosquitoes occurred for a longer period
of time due to the last WNV positive mosquito trapping occurring in late October. Mosquito
trapping started at the beginning of May and was extended until late November. The first hard
freeze, the typical weather indicator used as the ending of the WNV mosquito season, was recorded
in mid-November.
There are many staff members across the organization that are involved in the City of Denton’s
Mosquito Surveillance and Response activities. These staff members include the Drainage
Department, Public Communication Office, Technology Services, the Water Department, and
Watershed Protection. The Mosquito Surveillance and Response Program would not be possible
without the dedication and hard work of these staff members. The University of North Texas
researchers (Dr. Jim Kennedy, Taylor Gillum, Gillian Graham, Katie Vazquez, Katherine Cline,
and Marti Sanders) and numerous other graduate students at the University of North Texas also
worked diligently to ensure mosquito monitoring efforts and local WNV testing was completed
efficiently. It is a great honor to work with this group of City of Denton staff members and UNT
researchers.
December 14, 2018 2018-179
I also would like to thank the City Council for their continuous support during the 2018 mosquito
season.
Please let me know if I can provided any additional information.
STAFF CONTACT:
Deborah Viera, Assistant Director of Environmental Services
940.349.7162
Deborah.Viera@cityofdenton.com