West Nile Virus Update: No New Human Deaths; Bird Numbers Still Rising

The number of San Diego County residents testing positive for West Nile virus leveled off this week. 

But with the numbers of dead, infected birds still rising, and with warmer weather expected this weekend after recent rains, County officials said people should continue to protect themselves from mosquitoes that can transmit West Nile virus.

The number of people listed as “confirmed” and “probable” human cases of West Nile virus in San Diego County increased from 30 last week to 31 this week, while West Nile virus deaths remained at five.

However, County vector control officials said they collected 18 more dead infected birds, bringing this year’s total to 321 — far greater than the 41 collected in 2014 and the most collected in the county since 2008, when 563 dead birds tested positive for the virus.

Statewide this year, 517 people have tested positive for West Nile virus and 28 people have died.

As of Nov. 4, the County reported:

  • 29 confirmed human cases, including five deaths and two probable cases. (Note: the California Department of Public Health uses patient symptoms and blood and spinal fluid tests to classify possible West Nile virus cases as “confirmed,” “probable,” “suspected” or “not a case.” For public reporting, state public health and the County consider both “confirmed” and “probable” cases as West Nile virus infections.)
  • 10 suspected human cases with state tests pending
  • 321 dead infected birds recovered
  • 48 batches of infected mosquitoes collected
  • Nine sentinel chickens testing positive for West Nile virus

Following this week’s rains, County officials urged people to remember to eliminate all standing water inside and outside their homes to make sure mosquitoes don’t have places to breed. They also recommended people follow the County’s “Prevent, Protect, Report” guidelines.

Prevent, Protect, Report:

Prevent Mosquito Breeding: Dump out or remove any item inside or outside of homes that can hold water, such as plant saucers, rain gutters, buckets, garbage cans, toys, old tires, and wheelbarrows. Mosquito fish, available for free by contacting the Environmental Health Vector Control Program, may be used to control mosquito breeding in backyard water sources such as unused swimming pools, ponds, fountains and horse troughs.

Protect Yourself from Mosquito Bites: Protect yourself from West Nile virus by staying inside when most mosquitoes are most active, at dusk and dawn. Wear long sleeves and pants or use repellent when outdoors. Use insect repellent that contains DEET, picaridin, oil of lemon eucalyptus, or IR3535. Make sure screens on windows and doors are in good condition and secured to keep insects out.

Report Dead Birds and Green Swimming Pools: Report dead crows, ravens, jays, hawks and owls, and green swimming pools to the Environmental Health Vector Control Program by calling (858) 694-2888 or emailing

For more information about West Nile virus, go to San Diego County’s “Fight the Bite” website.


Gig Conaughton is a communications specialist with the County of San Diego Communications Office. Contact