West Nile Virus, a mosquito borne disease, was first identified in Clark County in 2004. In response to this public health threat, the Southern Nevada Health District developed a Mosquito Surveillance program to monitor mosquito populations for diseases including West Nile Virus (WNV), Western Equine Encephalitis (WEE), and Saint Louis Encephalitis (SLE). Each year, SNHD staff set thousands of mosquito traps to accomplish this goal.

Aside from disease status, mosquito surveillance is used to identify the type of mosquitoes breeding in the community. In 2017, an invasive species of mosquito called Aedes aegypti was trapped in Clark County for the first time. This highly aggressive mosquito species is well adapted to living in urban environments and capable of spreading emerging disease like Dengue, Chikungunya, and Zika virus. Keeping an eye on the type of mosquito species is very important as it can be an early warning for new disease introduction to Las Vegas.

Each year, the SNHD mosquito surveillance program submits tens of thousands of mosquitoes to the Southern Nevada Public Health Lab for WNV, SLE, and WEE analysis. SNHD notifies the public when any of these mosquitoes test positive for any of these disease, prompting media releases and increased public education on breeding and bite prevention.

SNHD is a surveillance agency and does not perform control measures. However, mosquito breeding sources needing abatement are referred to Public Works, Parks and Recreation, and Code Enforcement offices within the six jurisdictional counterparts. To report a green swimming pool, contact your local Code Enforcement office for remediation.

The Southern Nevada Health District is the only entity in Clark County capable of monitoring mosquito populations across the six distinct jurisdictions within the county, including City of Las Vegas, unincorporated Clark County, City of Henderson, City of North Las Vegas, City of Mesquite and the City of Boulder City. If you are experiencing mosquito activity at your home, please contact our office at (702) 759-1633.

Annual reports detailing surveillance and control activities since 2004 can be found on the SNHD’s web site at /news-info/statistics-surveillance-reports/vector-borne-and-zoonotic-diseases/.