The disease surveillance program serves as an early warning system in the detection of mosquito-borne viruses that can infect people and animals.

The District uses the following factors to assess health risk in your community:

  • Higher-than-average daily temperatures
  • Mosquito Population Monitoring – Using traps set up in every community
  • Mosquito Testing for Diseases
  • Dead Birds – A CA state program: Dead birds help determine spread of West Nile virus
  • Sentinel Chickens – Chickens develop antibodies to West Nile virus, which can be detected by testing.

Using these measurements, the District is able to protect your health by responding appropriately to mosquito-borne disease threats.


Yearly Summary (2008-2016)

Human cases reported for LA County by Los Angeles County Department of Public Health


Year-to-Date Statistics for 2017

WNV+ = Number of West Nile virus positive samples confirmed

  • City or Community
  • WNV+
  • Artesia
  • 3
  • Bellflower
  • 4
  • Bell Gardens
  • 3
  • Boyle Heights
  • 4
  • Burbank
  • 5
  • Canoga Park
  • 4
  • Carson
  • 5
  • Castaic
  • 1
  • Cerritos
  • 7
  • Chatsworth
  • 7
  • Commerce
  • 3
  • Cudahy
  • 2
  • Diamond Bar
  • 3
  • Downey
  • 10
  • Eagle Rock
  • 5
  • East Los Angeles
  • 8
  • El Sereno
  • 3
  • Elysian Valley
  • 5
  • Encino
  • 13
  • Florence-Firestone
  • 3
  • Gardena
  • 4
  • Glendale
  • 8
  • Granada Hills
  • 4
  • Hacienda Heights
  • 6
  • Hawaiian Gardens
  • 5
  • Harbor City
  • 1
  • Highland Park
  • 4
  • Hollywood Hills
  • 1
  • Huntington Park
  • 1
  • La Habra Heights
  • 3
  • La Mirada
  • 9
  • Lakewood
  • 8
  • Lincoln Heights
  • 10
  • Long Beach
  • 4
  • Los Angeles - Downtown
  • 1
  • Los Feliz
  • 7
  • Lynwood
  • 3
  • Maywood
  • 3
  • Mission Hills
  • 1
  • Montebello
  • 6
  • Newhall
  • 4
  • North Hills
  • 7
  • North Hollywood
  • 14
  • Northridge
  • 7
  • Norwalk
  • 6
  • Pacoima
  • 1
  • Panorama City
  • 7
  • Paramount
  • 1
  • Pico Rivera
  • 9
  • Reseda
  • 5
  • Rowland Heights
  • 9
  • San Fernando
  • 4
  • San Marino
  • 2
  • San Pedro
  • 1
  • Santa Clarita
  • 4
  • Santa Fe Springs
  • 9
  • Sherman Oaks
  • 4
  • Signal Hill
  • 3
  • Silver Lake
  • 2
  • South Central
  • 2
  • South El Monte
  • 5
  • South Gate
  • 1
  • South Los Angeles
  • 2
  • South Park
  • 1
  • South Whittier
  • 4
  • Studio City
  • 6
  • Sunland
  • 2
  • Sylmar
  • 1
  • Tarzana
  • 4
  • Toluca Lake
  • 9
  • Tujunga
  • 1
  • Valley Glen
  • 2
  • Valley Village
  • 3
  • Van Nuys
  • 10
  • Watts
  • 3
  • West Hills
  • 6
  • Whittier
  • 7
  • Willowbrook
  • 5
  • Wilmington
  • 2
  • Winnetka
  • 4
  • Woodland Hills
  • 5
  •  
  • WNV+ total: 371
  • City or Community
  • WNV+
  • Chatsworth
  • 1
  • Cerritos
  • 1
  • Downey
  • 1
  • Encino
  • 1
  • Glassell Park
  • 1
  • Granada Hills
  • 3
  • Hollywood Hills
  • 1
  • Lakewood
  • 1
  • Long Beach
  • 6
  • Northridge
  • 1
  • San Fernando
  • 1
  • Santa Clarita
  • 3
  • Sherman Oaks
  • 3
  • Sun Valley
  • 1
  • Sylmar
  • 1
  • Tarzana
  • 3
  • Valencia
  • 1
  • West Hills
  • 1
  • Whittier
  • 1
  • Winnetka
  • 1
  • Woodland Hills
  • 3
  •  
  • WNV+ total: 36
  • City or Community
  • Date of 1st Detection
  • Number of WNV+
  • Encino
  • 7/17
  • 6
  • Long Beach
  • 8/9
  • 5
  • Los Angeles
  • 7/31
  • 7
  • Rowland Heights
  • 5
  • Santa Clarita
  • 7/31
  • 7
  • South El Monte
  • 3
  •  
  •  
  • Number of WNV+ total: 33