First West Nile virus-positive mosquitoes identified in Clark County this season
Public urged to “Fight the Bite”
FOR IMMEDIATE RELEASE:June 24, 2026
LAS VEGAS – The Southern Nevada Health District has identified the first mosquitoes of the season to test positive for West Nile virus. The mosquitoes were collected in the 89121 ZIP code as part of the Health District’s ongoing mosquito surveillance program. The Health District is reminding residents to take precautions and “Fight the Bite” to help reduce the impact of mosquitoes in the community.
The Health District began routine mosquito surveillance activities in March, approximately one month earlier than usual this year in response to warmer-than-average temperatures and rainfall across Clark County. Additional mosquito trapping and testing will be conducted in the area where the positive mosquitoes were identified to monitor mosquito activity and assess whether West Nile virus is continuing to circulate.
“The identification of West Nile virus in local mosquitoes is a reminder that residents should take steps to protect themselves from mosquito bites,” said Dr. Cassius Lockett, District Health Officer for the Southern Nevada Health District. “Simple actions such as using insect repellent, eliminating standing water and wearing protective clothing can help reduce the risk of mosquito-borne illness.”
The Health District’s Fight the Bite campaign encourages residents to:
- Eliminate standing water around their homes.
- Use an EPA-registered insect repellent and wear protective clothes.
- Report mosquito activity to the Health District’s surveillance program at (702) 759-1633.
- Report green pools to local code enforcement agencies.
West Nile virus is transmitted to people through the bite of an infected mosquito. Most people infected with the virus do not develop symptoms. However, some individuals may experience fever, headache, body aches, joint pain, vomiting, diarrhea or rash. In rare cases, infection can lead to serious neurological illness.
In 2024, 26 human cases of West Nile virus were reported in Clark County. No human cases were reported in 2025. Earlier this month, the Health District reported Clark County’s first human case of West Nile virus in 2026. The patient had traveled to another state where multiple human West Nile virus cases had been reported and was also present in Clark County during the incubation period.
The Health District is also monitoring the presence of Aedes aegypti, an invasive mosquito species capable of transmitting viruses such as Zika, dengue, yellow fever and chikungunya. For more information about mosquito surveillance, visit www.snhd.info/mosquito.
NOTE: Since the distribution of this news release, the Southern Nevada Health District has received notification of mosquitoes testing positive for West Nile virus in two additional ZIP codes: 89169 and 89139. With rainfall occurring across the valley today, the Health District is reminding residents to check for and eliminate standing water around their homes and properties to help reduce mosquito breeding sites.
The Health District’s weekly mosquito surveillance reports are available at www.southernnevadahealthdistrict.org/programs/mosquito-surveillance/arbovirus-update/.
The Southern Nevada Health District serves as the local public health authority for Clark County, Boulder City, Henderson, Las Vegas, Mesquite and North Las Vegas. The agency safeguards the public health of the community’s residents and visitors through innovative programs, regulations, and initiatives focused on protecting and promoting their health and well-being. More information about the Health District, its programs, services, and the regulatory oversight it provides is available at www.SNHD.info. Follow the Health District on Facebook, Twitter, and Instagram.