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2012 West Nile Virus Activity

This map details mosquitoes, dead birds, chickens, and horses that have tested positive for West Nile virus. You can zoom in and out of the map and click on the placemarkers to get a detailed description of the date the positive activity was confirmed and the approximate location.

May contain: cutlery, spoon, chart, and plot

 For information regarding human cases, please click here.


Mosquito Samples: 19
nDate CollectedCityCross StreetsSpecies
17/10BrentwoodGarin Pkwy x Spruce St.tarsalis
27/10BrentwoodChestnut St. x Sellers Ave.pipiens
37/16BrentwoodChestnut St. x Sellers Ave.pipiens
47/23BrentwoodGarin Pkwy x Spruce St.pipiens
57/26BrentwoodGarin Pkwy x Spruce St.pipiens
68/1BrentwoodGarin Pkwy x Spruce St.pipiens
78/6AntiochCavallo Rd. x Wilbur Ave.tarsalis
88/15BrentwoodChestnut St. x Sellers Ave.pipiens
98/20BrentwoodWaldon St. x Balfour Rd.tarsalis
108/22BrentwoodSellers Ave. x Redhaven St.pipiens
118/20KnightsenHolland Tracttarsalis
128/29KnightsenHolland Tracttarsalis
138/29Discovery BayNewport Dr. x Hwy 4tarsalis
148/27ByronByron Hwy x Byron Hot Springs Rd.tarsalis
159/4AntiochWilbur Ave. x Marie Ave.pipiens
169/10BrentwoodGarin Pkwy x Spruce St.pipiens
179/108th St. x H St.8th St. x H St.pipiens
189/19BrentwoodBalfour Rd. x Sellers Ave.tarsalis
199/19BrentwoodBalfour Rd. x Sellers Ave.pipiens
Dead Birds: 66
nDate ReportedCityCross StreetsSpecies
14/9Pleasant HillEllinwood Wy x Contra Costa Blvd.Stellar's Jay
26/8Walnut CreekGeary Rd. x Buena Vista Ave.American Crow
37/2BrentwoodBalfour Rd. x Walnut Blvd.American Crow
47/5Pleasant HillDoray Dr. x Contra Costa Blvd.American Crow
57/16Pleasant HillViking Dr. x Contra Costa Blvd.American Crow
67/16KnightsenSunset Rd. x Eden Plains Rd.American Crow
77/16Walnut CreekHutchinson Rd. x Walnut Ave.American Crow
87/25KnightsenSunset Rd. x Eden Plains Rd.American Crow
97/28El SobranteValley View Rd. x San Pablo Dam Rd.Western Scrub Jay
108/2OakleySandmound Blvd. x Bethel Island RoadAmerican Crow
118/7Discovery BayDiscovery Bay Blvd. x Willow Lake Rd.American Crow
127/25MartinezPine St. x Pacheco Blvd.Western Scrub Jay
138/8KnightsenSunset Rd. x Byron HwyAmerican Crow
148/9BrentwoodWalnut Blvd. x Balfour Blvd.Western Scrub Jay
158/16Pleasant HillBoyd Rd. x Pleasant Hill Rd.American Crow
168/20BrentwoodTwilight Ct. x Sunset Rd.American Crow
178/20BrentwoodShirley St. x Brentwood Blvd.American Crow
188/20AntiochMontara Dr. x Country Hills Dr.American Crow
198/21BrentwoodFairview Ave. x Central Blvd.Western Scrub Jay
208/21BrentwoodCypress Rd. x Sellers Ave.American Crow
218/22Walnut Creek1st Ave. x Buena Vista Ave.American Crow
228/22AntiochWorrel Rd. x Lone Tree Wy Western Scrub Jay
238/23OakleyO'Hara Ave. x W. Cypress Rd.American Crow
248/26Discovery BayNewport Dr. x Clipper Dr.American Crow
258/28ConcordConcord Blvd. x West St.American Crow
268/28Walnut Creek1st Ave. x Larkey Ln.American Crow
278/28ClaytonMorgan Territory Rd. x Marsh Creek Rd.Western Scrub Jay
288/29BrentwoodJohn Muir Pkwy x Ventura Dr.American Crow
298/29BrentwoodWildberry Dr. x Valley Green Dr.American Crow
308/29AntiochLone Tree Way x Dallas Ranch Rd.American Crow
319/4San RamonSunnybrook Pl. x Yosemite Ave.Western Scrub Jay
328/27ConcordMendocino Dr. x Clayton Rd.Western Scrub Jay
338/27BrentwoodFairview Ave. x Sand Creek Rd.Western Scrub Jay
348/28AntiochWilbur Ave. x Almond St.Western Scrub Jay
359/6ConcordClayton Rd. x East St.American Crow
369/7ConcordConcord Blvd. x Landana Dr.American Crow
379/10ConcordConcord Blvd. x Bailey Rd.American Crow
389/10BrentwoodSand Creek Rd. x Hwy 4American Crow
399/11BrentwoodCentral Blvd. x Minnesota Ave.American Crow
409/11AntiochBlack Oak Way x Eagleridge Dr.Western Scrub Jay
419/13Pleasant HillPatterson Blvd. x Oak Park Blvd.American Crow
429/10ConcordBailey Rd. x Concord Blvd.American Crow
439/11KnightsenKnightsen Ave. x Delta Rd.American Crow
449/18BrentwoodSunset Rd. x Byron HwyAmerican Crow
459/19ConcordConcord Blvd. x Bailey Rd.Western Scrub Jay
469/20BrentwoodFairview Ave. x Sand Creek Rd.American Crow
479/20ConcordRisdon Rd. x Getoun Dr.American Crow
489/21OakleyLaurel Rd. x O'Hara Ave.Western Scrub Jay
499/17ConcordBabel Ln. x Clayton Rd.Western Scrub Jay
509/25ConcordClayton Rd. x West St.American Crow
 519/27Pleasant HillGeary Rd. x Pleasant Hill Rd.American Crow
529/28Walnut CreekN. Main St. x San Luis Rd.American Crow
5310/1ConcordThornwood Dr. x WIlson Ln.American Crow
549/19Pleasant HillPaso Nogal x Morello Ave.American Crow
559/21Discovery BayDiscovery Bay Blvd. x Cabrillo Pt.Western Scrub Jay
5610/2BrentwoodBalfour Rd. x Griffith Ln.American Crow
5710/3BrentwoodShirley St. x Brentwood Blvd.American Crow
5810/5KnightsenByron Hwy. x Eagle Ln.American Crow
599/26KnightsenByron Hwy. x Eagle Ln.American Crow
609/27ConcordConcord Blvd. x N 6th St.Western Scrub Jay
619/28OakleyO'Hara Ave. x Laurel Rd.Western Scrub Jay
6210/8ConcordConcord Blvd. x Mendocino Dr.Western Scrub Jay
6310/12BrentwoodBalfour Rd. x Sellers Ave.American Crow
6410/11Discovery BayDiscovery Bay Blvd. x Riverlake Rd.American Crow
6510/3OakleyLaurel Rd. x O'Hara Ave.Western Scrub Jay
6610/5Walnut CreekSan Luis Rd. x Larkey Ln.Western Scrub Jay


Sentinel Chicken Flocks: 2
#/10Date BleedArea
3/108/13Holland Tract
1/108/27Holland Tract
2/109/10Holland Tract

Note: Chickens do not die from West Nile virus. They develop antibodies to the virus which is detected in their blood.


Horses: 0
nDate ReportedCityDead/Euthanized