Mosquito and West Nile Information

Mosquito Season 2019


Mosquito Season 2019 is underway!! March 1 is the official start date for the full slate of mosquito surveillance and response in Rowlett.

We need everyone's help...Report All STAGNANT WATER, POOLS, SPAS, ETC.

 While staff respond to complaints, it is impossible to see all sources of stagnant water or breeding sites. We ask all residents to please report all stagnant water sources to Environmental Services by email.

Please be sure you give as much detail as possible including the correct physical address of the complaint, your name and contact information in case City staff needs to get back with you for more information. Reminder: complaints do remain anonymous. The City of Rowlett's Mosquito Action Plan can be accessed here.

City of Rowlett Mosquito Information

City staff work in conjunction with Dallas County Mosquito Control to battle mosquito borne diseases. As noted in the Mosquito Action Plan, managing mosquitoes takes an integrated approach. City response cannot rely solely on larviciding, adulticiding, or only on source reduction. Mosquito management must include all of the steps working together, including the public education, assistance, and 4D's.

 When conducting surveillance and larviciding activities, the source of high concentrations of mosquitoes or repeat positive test results may not be readily observed. A large open pond, with no vegetation, no shade, and with ample wind action on an active construction site is not a spot for mosquito egg laying. A road side ditch containing "stinky" water and much grass and decaying organic matter with no flow and mostly protected from wind is a prime location. The sources are not always easy to find and may take staff multiple visits to the area to find the source if they ever are able to find it-- sources may be in the middle of a field, on private property, in bordering city, etc. City departments work together and ask our residents to do the same in reporting these conditions. Environmental Services will investigate all complaints reported. After a rain event, staff typically does not respond to certain water complaints until at least 3 days post event.

 Please note the following pertinent details regarding mosquito spraying, etc. The City of Rowlett will continue to work with residents on complaints regarding standing stagnant water. Dallas County has informed Rowlett that in the event of a positive sample of mosquitoes, they will be making every effort to have vehicles spraying within 24 hours and in some instances the night of notification (limited special circumstances only). Rowlett is working very hard to ensure as much notification as possible for our residents. Residents in affected areas will be notified by telephone notification (if they have a Connect Rowlett account) at approximately 630 p.m. Additional notifications will be published through social media and city webpage news.

Sign up for Connect Rowlett.

The GIS department has developed a google map layer that works with smartphones, both Android and IOS. The link to the map will be included in the City media outlets. Dallas County also has an interactive map which can be linked at the bottom of this page.

If you have questions or special circumstances relevant to mosquitoes or spraying, please contact Environmental Services 972-412-6125, option #9.

Mosquito Dunks Available?

The City of Rowlett has received an allotment of Mosquito Dunks from Dallas County for dispersal to local residents. If you are a Rowlett resident and need larvicide mosquito dunks please visit 3901 Main Street.  Please be sure to bring proof of residency.

If you have any questions, please contact the Rowlett Environmental Services Office at 972-412-6125, option #9.

City of Rowlett Continuing Partnership with Dallas County for 2019 West Nile Virus Prevention Campaign

"Dallas County Health and Human Services strives to protect the health of the citizens of Dallas County through disease prevention and intervention, and through promotions of a healthy community and environment. This is done through assessment, community input education, disease monitoring, regulation, and health services that help control the spread of disease."

Mosquito traps will be set weekly in six (6) zones determined by Dallas County Health and Human Services. See attached Rowlett map (PDF) for zone locations.

In the event that the West Nile Virus is detected in mosquito samples, the following will occur:

  • Advise the public and emphasize source reduction, personal protection and disease symptoms
  • Ground-based spraying will occur within 24-72 hours (weather permitting) around positive trap zone

When ground spraying is to occur, it will be documented and placed on Social Media, and updated on the City Website as soon as information is available. Citizens within the affected area will also be notified by Connect Rowlett at 630pm the night prior and each night of spraying

Access a spray map of the affected area.

What MUST I Do?

Mosquito Proof. Remember the Best Offense is a Good D-fense.


  • Wear long, loose and light-colored clothing to avoid mosquito bites when outside. 


  • Use insect repellent products with "DEET" or other EPA approved repellents and follow product instructions. 


  • Get rid of or report ALL standing water.
  • Empty, remove, cover or turn upside down any containers that will hold standing water (bottles, cans, tires, buckets, flower pots etc.). 
  • Change water in pet dishes, wading pools and birdbaths several times a week. 
  • Cover trash containers so they will not collect water. 

Dusk & Dawn 

  • Stay indoors during dusk and dawn hours—when mosquitoes are most active.

West Nile Virus Information

West Nile Virus is a disease that is spread by the bite of a mosquito. Mosquitoes become infected when they feed on the blood from infected birds. The infected mosquitoes can then transmit West Nile Virus to humans and animals.

West Nile disease can vary in severity. People 50 years of age and older have the highest risk of severe disease. 

  • Severe West Nile (Neuroinvasive Disease) - infections can cause neurologic complications such as encephalitis. Symptons include headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. It is estimated that approximately 1 in 150 persons infected with the West Nile virus will develop a more severe form of disease.
  • West Nile Fever - It is estimated that about 20% of people who become infected with WNV will develop West Nile Fever. Symptoms include fever, headache, tiredness and body aches. Occaisionally a skin rash on the trunk of the body and swollen lymph glands will occur. While the illness may last only a few days, even healthy people have reported being sick for several weeks.

 Mosquito season in Dallas County runs from April to October/November with peak activity in mid-late July thru August. Residents are encouraged to be vigilant and on heightened alert during these months.

West Nile FAQ's


Is it contagious?

No. WNV is not spread through contact from person to person or from animal to person.

How is it diagnosed?

Diagnosis of WNV requires a special blood test. Anyone who experiences symptoms of severe WNV illness should see a physician as soon as possible.

What is the treatment?

There is no specific treatment for WNV infection. Patients receive supportive medical care and rehabilitation if needed.

What if I’m not experiencing any symptoms?

Most infected people will show no symptoms. Symptoms typically develop between 3 to 14 days after a mosquito bite.

For DCHHS West Nile Virus FAQs see attached sheet (PDF).

More Information and Links

For more information pertaining to mosquitoes and West Nile please visit:

Dallas County website.

Center for Disease Control West Nile Virus Q&A