Mosquito Viruses

General Information

According to Dallas County Health and Human Services (DCHHS), there have been no reports of locally-acquired cases of Chikungunya, Dengue and Zika viruses. However, imported cases make local spread possible because the mosquitoes that can transmit those viruses are found in Dallas County. Mosquito season in Dallas County is officially from May to October, but DCHHS has seen mosquito activity in other months while conducting year-round surveillance.

Chikungunya, Dengue and Zika viruses are not spread directly from person to person. All three viruses are spread by the bite of an infected Aedes species mosquito. The mosquitoes are aggressive daytime biters, prefer to bite people, and live indoors and outdoors near people. Mosquitoes become infected when they feed on a person already infected with one of the viruses. Infected mosquitoes can then spread it to other people.

Chikungunya, Dengue and Zika viruses are endemic to tropical regions such as Central and South America, and the Caribbean.


Although each virus has a unique set of symptoms, an infected person may experience fever, headache, rash, muscle or joint pain, usually within a week of being bitten by a mosquito carrying one of the viruses. There is no vaccine to prevent Chikungunya, Dengue or Zika.

There is no specific treatment for any of the viruses. However, supportive therapy is helpful with managing symptoms.


DCHHS recommends the 4Ds to reduce exposure to mosquitoes at all times:

  • DEET all day, every day: Whenever you're outside, use insect repellents that contain DEET or other EPA approved repellents.
  • Dress: Wear long, loose and light-colored clothing outside.
  • Drain: Drain or treat all standing water in and around your home or workplace.
  • Dusk & dawn: Limit outdoor activities during dusk and dawn when mosquitoes are most active.


Travelers with symptoms are advised to see a healthcare provider if they have visited an area where the viruses are present, and tell the healthcare provider when and where they traveled.

Pregnant women and women who are trying to become pregnant, should discuss travel plans with their healthcare providers and consider postponing travel to affected areas.


Students who have any questions or concerns may contact the Student Health Center at 972-883-2747 or [email protected].

Faculty and staff with questions should contact their health care provider or visit the Dallas County Health and Human Services website.