LAS VEGAS (KTNV) — The number of confirmed cases of West Nile virus in Clark County has risen again as mosquitoes positive for the virus are found in 44 Southern Nevada zip codes.
In its latest mosquito abatement report, the Southern Nevada Health District listed 14 confirmed cases of West Nile virus in Clark County. That's up from our last review of the numbers on July 10, when 10 cases were reported.
The report also states that 17% of mosquitoes tested in Clark County had the virus.
For some context, this number is a substantial increase compared with recent years. In 2023, there were only two human cases of the virus in Clark County. In 2022 and 2021, there were zero cases.
The Health District's latest data would make Nevada one of the states with the most West Nile cases in the country, according to the latest data from the Centers for Disease Control and Prevention.
Thousands of mosquitoes from different sample pools throughout Southern Nevada are tested in an effort to track the potential threat of West Nile in our community. Those tests have found West Nile-positive mosquitoes in 44 zip codes.
Here's the list (a zip code in bold indicates a new addition to the list since the last report):
- 89002,
- 89004
- 89014
- 89025
- 89030
- 89031
- 89032
- 89074
- 89081
- 89084
- 89086
- 89101
- 89102
- 89103
- 89104
- 89107
- 89108
- 89110
- 89115
- 89117
- 89118
- 89119
- 89120
- 89121
- 89122
- 89123
- 89124
- 89128
- 89129
- 89130
- 89131
- 89134
- 89135
- 89138
- 89139
- 89141
- 89143
- 89144
- 89145
- 89146
- 89147
- 89148
- 89149
- 89169
Why are the numbers so high this year compared to recent years?
Channel 13 anchor Joe Moeller wondered that very thing back in late May after he noticed more mosquitoes around his home in the Lone Mountain area. He's been keeping tabs on the number of West Nile cases in the valley ever since.
A mosquito disease expert from UNLV told Joe Southern Nevada has actually seen a "massive uptick" in our mosquito population in recent years.
A big part of the problem is a specific breed of mosquito called Aedes aegypti — a much smaller pest that typically bites during the day and prefers biting people, UNLV's Louisa Messenger told Joe.
Another issue with Aedes aegypti you may not be aware of — it requires a much smaller amount of standing water to breed. In some cases, as little as a bottle cap of water could allow the mosquitoes to reproduce.
WATCH: Mosquito disease expert Louisa Messenger explains why we're seeing so many mosquitoes in Las Vegas lately:
What are the signs of West Nile virus infection?
According to the CDC, roughly 80% of people infected by West Nile virus do not develop any symptoms. Others develop some symptoms that can include fever, headache, body aches, joint pains, vomiting, diarrhea or rash.
About one in 150 people infected with West Nile develop more severe, neuorinvasive symptoms of illness, the CDC notes.
Kathleen, a North Las Vegas resident whose husband was recently hospitalized because of West Nile virus, saw Joe's reporting and wanted to share her story.
She told us her husband was very fatigued at first, then developed severe headaches and "said it felt like his eyes were popping out of his head."
After a series of tests, doctors determined he had West Nile. In light of the recent uptick in cases here in Clark County, the Southern Nevada Health District told us they've also put out an alert to hospitals urging them to test for West Nile virus when patients show up with symptoms like Kathleen's husband.
WATCH: Kathleen shares her story after her husband is hospitalized with West Nile virus:
So, with that information in mind, what can you do?
The Health District recommends taking the usual precautions to prevent being bitten — wear an insect repellent with DEET. Long sleeves and pants are recommended, as well (though we all know how that goes when temperatures are in the triple digits).
Removing all standing water from around your home to prevent mosquito breeding is another tip. You're also urged to report things like green swimming pools in your area if you see them. There are a number of Clark County agencies listed on the Health District's website to help with that.
You can take other preventative measures like pest control, as well. A local company Joe spoke with showed him two different treatments — one being a small trap placed in the shade that has water, a screen, and an additive that draws mosquitoes to the trap. There's also fogging. (Clark County actually has a cool new drone for this that Joe got to see in action last month.)
If you want to talk to Joe about the mosquito problem in your area, you can email him at joe.moeller@ktnv.com or reach out on social media.
