LAS VEGAS (KTNV) — More mosquitoes in Southern Nevada are testing positive for West Nile virus, but that isn't the only concern.
The populations of certain mosquitoes are exploding here, which is why many of us are getting more bites compared to years past.
That's according to UNLV professor and mosquito disease expert Louisa Messenger, who says we have seen a "massive uptick" in our mosquito population over the past few years.
On Monday, the Southern Nevada Health District reported mosquitoes in 16 zip codes had tested positive for West Nile virus, and in two zip codes mosquitoes positive for St. Louis encephalitis were found.
Those findings represent "the highest level of activity in the program's history this early in the season," the health district said.
Las Vegas residents are noticing the difference. Anita Dominguez tells me she bought traps and screens to try and stop the pests.
"They attack your ankles and arms," Dominguez said. "I had 15 to 20 bites at one time."
A big question I noticed across social media — especially from people born and raised here — is why there seem to be so many more mosquitoes now, compared to years past. I asked Messenger about that.
"We have always had mosquitoes here in Las Vegas, just at much lower densities," she told me. "And we didn't have this species until very recently."
The species she's referring to is Aedes aegypti, a much smaller breed of mosquito that typically bites during the day and prefers biting people, unlike other species of mosquito.
Messenger tells me Aedes aegypti was first detected in Southern Nevada in 2017.
"Initially it was only localized to five or six different zip codes, but last year it became explosive," Messenger said. "It is already bad, and it's only June."
There's another reason Aedes aegypti are able to infest so much of the valley. Experts tell me they're able to breed in much smaller amounts of water than the mosquitoes we're used to dealing with.
"These ones will rarely breed in large bodies of water. It is much smaller," Messenger said.
WATCH: Louisa Messenger explains why we're seeing so many mosquitoes in Las Vegas lately:
As to how they got here and how they are spreading, that's one of the projects Messenger is working on at UNLV.
Her advice to those who are sick of getting bit: Clear standing water from around your property, no matter how small the amount. As much as a bottle cap of water can be enough for Aedes aegypti to breed.
Wearing insect repellent can help protect against all mosquitoes, including the disease-carrying ones. Experts also recommend wearing clothing that covers your limbs when you spend time outside.
