Cedar Park Mosquito Sample Tests Positive For West Nile Virus

CEDAR PARK, TEXAS — Yet another mosquito sampling has tested positive for the West Nile virus in Cedar Park, this time in the area of Parmer Lane/Brushy Creek Road, officials said Wednesday.

The good news is a follow-up sampling of mosquitoes taken at an expanded trapping site in southwest Cedar Park near the intersection of Lakeline Boulevard and Cypress Creek Road has tested negative for West Nile Virus. The bad news: A new sampling of mosquitoes trapped in the area near Brushy Creek Road west of Parmer Lane has tested positive for West Nile virus.

That's the latest report from Cedar Park health officials issued on Wednesday. The testing is part of the city's proactive participation in the Williamson County and Cities Health District’s mosquito management program, officials explained.

This marks the fourth time since August that a mosquito sample has tested positive for the virus since August. The previous positive samples were:

• In the Cypress Creek/Sun Chase area from a sample collected Sept. 27 that came back positive on Oct. 2 during regular testing.
• An expanded testing site at Cypress Creek/Lakeline first tested Sept. 13 that came back positive from the lab on Sept. 18.
• A regular testing sample at the Cypress Creek/Sun Chase site collected on Sept. 6 that tested positive on Sept. 11.
• A sample at Cypress Creek/Sun Chase derived from regular testing on Aug. 2 that came back positive on Aug. 6.

Two recent samples have come back negative for West Nile virus from the Cypress Creek/Lakeline testing site on Oct. 10 and Sept. 25, according to a city-devised tally.

Health officials said the results were indicated in a lab test at the Texas Department of State Health Services lab in Austin. Given the new positive sample, city officials reiterated the need for residents to rid their properties of stagnant water posing as ideal breeding spots for mosquito larvae. The advice takes on added urgency given recent rainfall.

"The city has been diligently working to drain and treat standing water from this week’s rainfall," city officials said in a press advisory. "Mosquitoes cannot breed without standing water. The city thanks residents for their hard work in draining and treating standing water at their own homes. However, the city and Health District strongly encourage everyone to remain vigilant about protecting themselves from mosquito bites and preventing mosquito breeding on their personal property – especially considering this week’s rainfall."

There are currently no reported human cases of West Nile Virus in Cedar Park, officials stressed. What's more, Williamson County has seen no reported human cases since 2016, officials added. West Nile Virus, officials noted, should not be confused with other mosquito-borne viruses. For more information about West Nile Virus visit www.wcchd.org or www.txwestnile.org.

The Health District now has four traps it uses on a regular basis, to capture mosquitoes at specific locations throughout Cedar Park. The species that has tested positive is Culex quinquefasciatus (southern house mosquito), which has a flight range of about one mile, according to city officials.

"Any time there is a positive West Nile virus test result, the Health District does expanded trapping at ten additional locations," officials explained. "If testing from expanded trapping yields a negative result, trapping returns to regular and not expanded operations. While trapping has returned to normal in the area of southwest Cedar Park due to this latest negative follow-up result, the Health District is conducting expanded trapping in the area of Brushy Creek Road and Parmer Lane due to this new positive result in this area."

City officials added they have maintained particular focus on draining and treating any standing water on city-owned property throughout the municipality, and continue to follow the Health District’s Best Practices for Integrated Vector Management (IVM) — which call for continued enhanced monitoring and testing and increased public outreach and education.

But the city needs citizens’ continued help in mitigating the mosquito-born virus, officials said. "Because mosquitoes breed in standing water the city is imploring residents to continue draining or treating any standing water on their own property," officials wrote in a press advisory. Residents may also report standing water on public or private property by using the CP Connect 2.0 app or www.cedarparktexas.gov/reportaproblem so that city crews can investigate and take appropriate action.

At the core of the Parks and Recreation Department efforts at mosquito control are bacillus thuringiensis (Bt) larvicide tablets placed at public property (such as parks) to treat any standing water that cannot be drained, according to information provided by the city. Bt is a naturally-occurring bacteria that is harmless to people and most pets but it interrupts the reproduction cycle of mosquitoes. You can find Bt for home use at most “big box” hardware retailers.

The widespread use of larvicide tablets by Cedar Park in lieu of or in tandem with spraying areas of concern — as other municipalities perform — is contingent on a municipal focus on larvae rather than adult mosquitoes, Cedar Park spokeswoman Jennie Huerta told Patch in response to questions.

"We cannot speak for other cities, but can tell you that we follow the Williamson County and Cities Health District’s Best Practices for Integrated Vector Management, which is a phased response and does not call for spraying at this stage," Huerta wrote in an email in response to questions from Patch. "It is important to note that spraying only kills adult mosquitoes and not the countless eggs they leave to hatch. This is why the Health District recommends draining and treating standing water as the most effective way to control the mosquito population. The city has been doing this on city-owned land and is asking residents to do the same."

Which is not to say other methods are off the table, Huerta suggested, depending on results from future testing sites: "Keep in mind that this is the first positive result we’ve seen this year from the trap near Parmer Lane and Brushy Creek Road and we are awaiting results from expanded trapping to determine additional actions. Also, this week’s result from expanded trapping in southwest Cedar Park were negative. This negative result returns us to the Health District’s regular trapping and does not call for additional actions at this stage."

According to the Centers for Disease Control & Prevention, mosquito control trucks spray very small amounts of insecticide into the air to kill mosquitoes, delivered as a fine mist that acts as a fogger. Such adulticide sprays immediately kill flying mosquitoes, according to the CDC. Conversely, larvicide sprays kill mosquito larvae that hatch from eggs and lasts longer than adulticide sprays. Both products will temporarily reduce mosquito populations in an area, CDC officials note, but neither permanently gets rid of them.

Truck spaying does not harm people, pets, animals or the environment, CDC officials noted.

Related stories:

Cedar Park Mosquito Sampling Tests Positive For West Nile Virus

Cedar Park Mosquito Sample Tests Positive For West Nile Virus

Cedar Park Mosquito Samples Negative For West Nile Virus

Cedar Park Mosquito Sample Tests Positive For West Nile Virus

2nd Mosquito Sample In Cedar Park Tests Positive For West Nile

Cedar Park Mosquito Sampling Tests Positive For West Nile Virus

Cedar Park West Nile Tests In Mosquitoes Negative For 2 Straight Weeks

3rd Cedar Park Testing Site Negative For West Nile

4th Cedar Park Mosquito Sampling Tests Positive For West Nile

Mosquito Tests Positive For West Nile Virus In Cedar Park

Cedar Park Officials Report No New West Nile Virus Samples

What you can do

Mosquitoes breed in standing or stagnant water. Eliminating places where mosquitoes can breed and reducing the chances of mosquito bites are the most effective lines of defense against exposure to West Nile Virus. As part of its Fight the Bite campaign the Health District recommends the 3 Ds of mosquito safety.

• Drain standing water in flower pots, pet dishes or clogged gutters so mosquitoes don’t have a place to breed and treat water that can’t be drained.
• Defend by using an EPA-approved insect repellent.
• Dress in long sleeves and pants when outdoors.

Residents aware of a location of stagnant water on public or private property, are urged to report it to the city’s Code Enforcement Division via www.cedarparktexas.gov/ReportaProblem, the CPConnect 2.0 app on your mobile device or e-mail at code@cedarparktexas.gov. For more information on mosquito safety, visit the Williamson County and Cities Health District’s website by clicking here.

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