Mosquitoes are having a banner year in Clark County.
The Southern Nevada Health District has captured and submitted 20,041 mosquitoes for testing so far in 2026, more than double the 9,888 recorded through the same period last year, according to health district data.
Vivek Raman, the environmental health supervisor of the health district and supervisor of its Mosquito Surveillance program, pointed to weather patterns as the most significant indicator of mosquito activity.
Mosquitoes can thrive in higher temperatures, and Las Vegas has already experienced record-breaking heat this year.
The health district responded to the abnormal weather by setting mosquito traps in early March, one month earlier than usual. Mosquito season typically lasts between late April and late October.
Some parts of the Las Vegas Valley have reported higher densities of mosquitoes than others, according to Louisa Messenger, an assistant professor at UNLV’s School of Public Health.
She said places like Summerlin, with an abundance of artificial water features, have become hot spots for Aedes aegypti, an aggressive species that can spread diseases not yet seen in the valley.
Over 92 percent of tested mosquitoes this year are the species Culex quinquefasciatus, which can carry the potentially deadly West Nile virus.
The health district last week reported the county’s first case of West Nile virus this year but has not yet identified the pathogen in any of its tested mosquitoes.
Whether West Nile virus will appear in Las Vegas’ mosquitoes is difficult to predict, Raman said, as mosquitoes must bite infected birds, then bite a human to spread the disease.
Feeling the bite
Though she studies mosquitoes, Messenger said the trends she has followed are starting to hit home. This is the first year since she moved to the valley in 2022 that she has encountered mosquitoes at her Henderson residence, she said.
“They’re here now, and they’re here to stay,” Messenger said of mosquitoes in the valley.
Others online have expressed discomfort from the increasingly prevalent pests.
“My arms, legs and back are covered in bites,” one user wrote earlier this year in a Reddit post in the subreddit r/vegaslocals. Another user said he had recently had his home treated for pests and that the technician told him mosquito activity was the worst he had ever seen.
While temperate mosquito-breeding temperatures have defined the year so far, Messenger said the valley is now at a “tipping point” for mosquito season.
Mosquito populations could thrive if current weather conditions persist, but the pests could perish should extreme summer temperatures arrive, she said.
“We’re, I’d say, quite mild by Vegas summer standards,” Messenger said. “It’s hot, but it’s not oppressively hot. That’s perfect for mosquitoes. That gives them more time to reproduce in the environment, and it gives it a longer period of time before it becomes too hot for them to survive.”
Messenger said unpredictable weather caused by climate change and an El Niño weather pattern expected to form this summer have made it especially difficult to determine how mosquitoes may fare this year.
To beat the bites, Messenger recommended valley residents apply topical repellents and wear long-sleeved clothing.
Raman stressed that homeowners should reduce stagnant water on their property to reduce breeding sources for mosquitoes.
“Prevention starts in your backyard,” Raman said. “It’s a communitywide effort to prevent mosquito breeding.”
Contact Alex Streinger at astreinger@reviewjournal.com. Contact Spencer Levering at slevering@reviewjournal.com or 702-383-0253.
