Mosquito season takes hold as seventh person dies of West Nile

A Dallas woman has died from West Nile virus, local health officials announced.

Less than a week ago, a woman in her 50s was identified as Dallas County’s sixth person with West Nile virus, Christian Grisales, spokesperson for the Dallas County Health and Human Services, told USA TODAY. On Tuesday, health officials announced she had become the county’s first West Nile death this year, at the start of the season when cases begin appearing when people get bit by infected mosquitoes.

West Nile is the leading cause of mosquito-borne disease in the continental U.S., according to the Centers for Disease Control and Prevention. Nationwide, preliminary reports submitted to the CDC show at least seven people have died from West Nile in 2024.

The Dallas woman, who had underlying health conditions, was diagnosed with West Nile neuroinvasive disease, a severe form of infection that can produce meningitis, encephalitis or paralysis, or a combination of these illnesses, county health officials said.

“This heartbreaking tragedy underscores the critical importance of safeguarding against mosquito bites, which can transmit several diseases including (West Nile virus),” Dr. Philip Huang, director of Dallas County Health and Human Services, said in a statement.

In Dallas County, the number of mosquito pools harboring West Nile is notably high this year, Grisales said. The woman died in North Dallas, where at least three people had been infected with West Nile this year, county data showed.

Texas health officials confirmed the region's first human case of West Nile in early July, and they worried that recent storms would create habitats of standing water for infected mosquitoes to thrive. As of Tuesday, officials said, two people in the state had died from West Nile this year. A California man and an Oklahoma resident also died from the virus in July.

Across the U.S., 103 people in 26 states have contracted West Nile virus this year, CDC data shows. Of those, 68 people have contracted the rare, neuroinvasive form of the disease. The seven reported deaths in the U.S. in 2024 are about on par with the number of reported deaths last summer at this time, Kate Fowlie, a CDC spokesperson, said in an email. Last year, 182 people died of the disease and more than 2,500 became infected with the virus.

Historic data from the CDC shows there have been more than 59,000 cases and nearly 3,000 deaths since 1999, when West Nile was first introduced in the U.S.

Fowlie added this is the season when West Nile cases increase. Early cases generally appear in the summer, and deaths usually continue into the fall.

West Nile symptoms, prevention

The incubation period after a person becomes infected with West Nile usually ranges from two days to two weeks. Though most people don’t develop symptoms, about 1 in 5 infected people develop a fever and other symptoms, such as headache, body ache, vomiting, diarrhea and rash, the CDC said. About 1 in 150 people develop serious illness that can have long-term neurologic effects. About 10% of cases involving the neuroinvasive form of disease become fatal, according to the CDC. There is no vaccine against West Nile.

Case counts fluctuate in part because of periodic epidemics, the CDC said. Officials also project that a warming planet has fostered more environments for West Nile to fester as mosquitos become infected and pass the disease on to people.

Dallas County health officials urged people to follow the “Four Ds” to protect themselves against West Nile and other mosquito-borne diseases when outside.

• DEET: Use insect repellants with DEET or other ingredients approved by the Environmental Protection Agency.

• Dress: Wear long, loose and light-colored clothing to cover the skin.

• Drain: To prevent mosquito breeding, remove standing water around your home or work.

• Dusk to dawn: Limit time outdoors at peak mosquito hours.

Indoors, the CDC recommends using window screens or air conditioning whenever possible.

This article originally appeared on USA TODAY: West Nile kills Texas woman as mosquito season takes off