Chicken in San Benito County tests positive for West Nile Virus

For the first time since 2013, a chicken has tested positive for West Nile Virus


On Sept, 1, the California Department of Public Health (CDPH) announced two confirmed deaths in California due to West Nile virus (WNV). The deceased persons were residents of Kern and San Bernardino counties.

Unrelated to these human deaths, a chicken in San Benito County has had a positive West Nile Virus test result.

“In San Benito County we just received confirmation that one sentinel chicken tested positive for the West Nile Virus,” stated Karen Overstreet, San Benito County Agricultural Commissioner.

In response to this positive case, additional traps have been deployed in the surrounding area and mosquitoes trapped will be tested for West Nile Virus. “As a preventive measure we remind the public to remove or drain any standing water and to keep current on their horses’ vaccinations,” stated Overstreet.

“This is the first detection of West Nile virus in San Benito County since 2013, so we will be closely monitoring throughout the County,” said San Benito County Health Officer Dr. Gail Newel. “West Nile virus can cause a deadly infection in humans, and the elderly are particularly susceptible.”

Newel stated in the news release, “August and September are peak periods of West Nile virus transmission in the State, so we urge everyone to take every possible precaution to protect themselves against mosquito bites.”

The release stated that as of August 22, CDPH has reported 41 human cases of WNV from nine California counties this year. It said that 203 dead birds from 29 counties have tested positive for WNV in 2017.  2,040 mosquito samples from 24 counties have also tested positive for WNV this year.

“The numbers of WNV positive dead birds and mosquito samples are below those at this same time last year, but the number of positive mosquito samples exceeds the state’s most recent five-year average,” the report said.

West Nile virus is influenced by many factors, including climate, the number and types of birds and mosquitoes in an area, and the level of WNV immunity in birds. West Nile virus is transmitted to humans and animals by the bite of an infected mosquito. The risk of serious illness to most people is low. However, some individuals – less than one percent – can develop serious neurologic illnesses such as encephalitis or meningitis.

The notice from the San Benito County Agricultural Commissioner explained that people 50 years of age and older as well as individuals with diabetes or hypertension have a higher chance of getting sick, and are more likely to develop complications.

California Department of Health (CDPH) recommends that individuals protect themselves against mosquito bites and West Nile Virus by practicing the “Three Ds”:

  1. DEET – Apply insect repellent containing DEET, picaridin, oil of lemon eucalyptus or IR3535 according to label instructions. Repellents keep the mosquitoes from biting you. Insect repellents should not be used on children under two months of age.
  2. DAWN AND DUSK – Mosquitoes usually bite in the early morning and evening so it is important to wear proper clothing and repellent if outside during these times. Make sure your doors and windows have tight-fitting screens to keep out mosquitoes. Repair or replace screens that have tears or holes.
  3. DRAIN – Mosquitoes lay their eggs on standing water. Eliminate all sources of standing water on your property by emptying flower pots, old car tires, buckets, and other containers. If you know of a swimming pool that is not being properly maintained, please contact your local mosquito and vector control agency.

California’s West Nile virus website includes the latest information on WNV activity in the state. Californians are encouraged to report dead birds on the website or by calling toll-free 1-877-WNV-BIRD (968-2473).

For additional information, contact: 

Sam Perez, Public Information Officer, at 831-637-5367


Leslie David

Leslie David is a Bay Area independent reporter/producer and is a BenitoLink founding board member. She has produced for radio, television, newspaper and magazines in both California and Wyoming. She was with KRON-TV News in San Francisco as camera-woman, editor and field producer, where she won the Commonwealth Club's Thomas Storke Award with Linda Yee for their series on the Aids Epidemic. She started as a small market news reporter shooting her own 16mm film at KEYT-TV Santa Barbara. Leslie lives on a ranch with her family in San Benito County.