More mosquito samples test positive for West Nile virus in North Texas

North Texas — The Dallas County Department of Health and Human Services confirmed this week that five new mosquito samples tested positive for West Nile virus. The samples were taken in Mesquite and Irving.

Tarrant County found signs of the disease in mosquitoes in Arlington last month.

Experts say with recent heavy rainfall it's more important than ever for families to protect themselves from insects.

“Heavy rains increase the number of mosquitoes,” said Shelley Stonesipher, an expert on zoonotic diseases and an associate professor at the University of California, San Luis Obispo Health Science Center. “More mosquitoes mean a higher risk of mosquito bites and therefore a higher risk of contracting West Nile virus.”

Stonecipher studies infectious diseases that spread between animals and humans, and she's concerned about what kinds of infectious diseases could emerge in North Texas this year.

“Each of us has a job to do for our families, our neighbors and our communities to prevent mosquitoes from breeding in and around our homes,” Stonecipher said.

Most people infected with West Nile virus do not experience any symptoms, but it can be severe and even life-threatening for older adults and those with weakened immune systems.

Last year, Dallas County saw more than 20 cases of West Nile virus, including two deaths, and Tarrant County reported 12 cases.

Common symptoms are fever, headache, body aches, and a rash.

“Please take this seriously,” Stonecipher says, “use bug spray and reduce mosquito breeding sites in and around your home.”

The city and local health department are urging residents to patrol their properties now, throw away any items that have standing water, dispose of old tires and tarps and clean out gutters.

“All it takes is a capful of water to produce mosquito larvae that will hatch into adult mosquitoes,” said Jordan Balsek, consumer health inspector for the city of Fort Worth.

City mosquito watch teams are targeting areas with standing water where mosquitoes can breed, and recent rains in North Texas have left standing water everywhere.

“We've had a lot of complaints about puddles,” Balsek said.

The team also sets up more than 50 traps around the city each week to collect insects to test for diseases like West Nile virus and to know where to spray pesticides.

“West Nile virus can be a deadly virus, so it's really important that we have these traps,” Balsek said. “Although it's rare, it's something we take seriously.”

Fort Worth typically sees a spike in positive West Nile mosquito samples starting in late June.

“You're going to see an increase in July and August, then a decrease in September and October,” Balsek said.

She recommends keeping insect repellent on hand from now through fall.

The city is also advising people to take the following steps to protect themselves and their families:

• Empty and clean all outdoor containers, including pools, toys, planters, bird baths and trash cans, and discard any standing water in and around the home.
• Make sure water-storing containers such as buckets, water tanks, and rainwater tanks have tight lids to prevent mosquitoes from getting in and laying eggs.
• Clean your drains to prevent them from collecting water. Check your drains for any damage that could cause water to collect.
• Inspect your yard after every rain and empty any containers or areas that collect water. Also, keep an eye out for puddles that may contain condensation from air conditioning units.
• Install screens on windows and doors and repair holes in screens.
• Apply insect repellent whenever you are outdoors. Use a repellent that contains one of the following active ingredients: DEET, picaridin, lemon/eucalyptus oil, or another EPA-approved insect repellent.

Caroline Vandergriff

Caroline Vandergriff joined the CBS 11 news team in September 2019. She grew up in Arlington (go for it, Lamar Vikings!) and is excited to be back in her hometown of North Texas.