Dallas County Health and Human Services - 2377 N. Stemmons Freeway, Dallas, TX 75207
Telephone: 214-819-2000

Mosquitoes can transmit viruses such as West Nile, Chikungunya, Dengue and Zika.

It is important for Dallas County residents to take action to prevent exposure to mosquitoes. DCHHS recommends the 4Ds as precautions for protecting yourself, loved ones, and neighbors.

In addition to the 4Ds, travelers can protect themselves by doing the following:

  • Choose a hotel or lodging with air conditioning or screens on windows or doors.
  • Sleep under a mosquito bed net if you are outside or in a room that is not well screened.
woman applying insect repellent to a child

DEET All Day, Every Day: Whenever you’re outside, use insect repellents that contain DEET or other EPA approved repellents and follow instructions.

The mosquito that transmits West Nile virus is known as the southern house mosquito and is very active in Dallas County. For maximum protection during mosquito season, use insect repellent all day every day, and while indoors and outdoors. Always follow label instructions.

woman in light colored clothing

DRESS: Wear long, loose, and light-colored clothing outside.

Mosquitoes look for exposed skin and are more attracted to dark colored clothing. You can decrease exposure by wearing appropriate clothing. Wearing long sleeves and pants light in color are best. Never put mosquito repellent under clothing.

gutter with standing water

DRAIN: Remove all standing water in and around your home.

Mosquitoes breed and larvae develops in standing water. Mosquito populations can be reduced by eliminating breeding sources.Empty standing water from containers such as flower pots and kiddie pools. Bird baths and ponds should be cleaned and maintained. Old tires and other garbage can collect water. Dispose of garbage items appropriately. Drain and/or treat areas that collect water, such as gutters and storm drains. Low areas around landscapes that collect water can be filled with dirt to make leveled.

man and woman out at dusk

DUSK DAWN:Limit outdoor activities during dusk and dawn hours when mosquitoes are most active.

Mosquitoes that carry West Nile virus are more active at dusk and dawn. Mosquitoes that carry Chikungunya virus are more active during the day, but are out during dusk and dawn. For these reasons, it is important to wear insect repellent throughout the day during mosquito season and reapply per label instructions. Make sure window screens and screen doors are in good repair to keep mosquitoes from coming inside.

While all 4Ds are important, draining or treating standing water is especially crucial since mosquitoes breed in water. Treating standing water is most effective when mosquito activity actually begins.

Using Larvicides to Treat Standing Water

  • Larvicides are products used to kill immature mosquitoes before they become adults.
  • Standing water can be treated with EPA-approved larvicide products.
  • Tablet, pellet, granular, and briquet formulations of larvicides are available for retail purchase.
  • Larvicides are applied directly to water sources that hold mosquito eggs, larvae, or pupae.
  • When used well, larvicides can help reduce the overall mosquito burden by limiting the number of mosquitoes that are produced, according to the Centers for Disease Control and Prevention.
mosquitodunks mosquitobits
These images are examples of larvicide products. DCHHS does not recommend or endorse any specific type of product. Before using any product, consumers should always read and follow label instructions.

Read more about West Nile virus and download materials.

Read more about Chikungunya virus and download materials.

Read more about Dengue and download materials.

Read more about Zika virus and download materials.