The Mosquito District has received confirmation that six (6) more mosquito pools (groups of mosquitoes) and two (2) sentinel chickens have tested positive with West Nile virus (WNV). Mosquitoes carrying the virus have been found in south, central, and northern areas of the county. One of the positive chickens is located in Palermo, the other west of Chico. With increasing mosquito populations and the detection and wide-spread distribution of WNV within Butte County, the District URGES residents to drain any and all un-needed standing water, report any suspected mosquito-breeding sites to the District, and to protect themselves from the bites of mosquitoes by wearing an effective repellent, avoiding being outside during dusk and dawn, and/or wearing lose long pants and long sleeve shirt.

The District has been collecting extremely high numbers of the mosquito species that have the ability to transmit WNV throughout the county. The time to protect oneself from the bite of a mosquito is now!

WNV activity is continuing to increase throughout the state (see and Butte County is following that trend. Matthew Ball, District Manager for the Butte County Mosquito and Vector Control District stated, “Once the adult mosquito populations have been found carrying the virus, the mosquitoes then have the capability of infecting our residents. It’s imperative that residents assist with the prevention of mosquito breeding by inspecting and eliminating all standing water from their properties and to protect themselves from the bite of mosquitoes.”

The District's Assistant Manager, Doug Weseman said "with increased WNV activity being reported and identified by neighboring counties and the wide-spread distribution locally, it's crucial that residents protect themselves from mosquito bites. Residents should use mosquito repellents when they go outdoors, and/or wear long sleeves and pants especially at the times when mosquitoes are most active (mornings and evenings). WNV is preventable, you only need to prevent the mosquito bite!" The virus is usually prevalent from May through October when mosquitoes are most abundant. Mosquitoes contract the virus when they feed on infected birds, then spread the virus when the mosquitoes seek other hosts to bite.

WNV has been identified in Butte County every year since its arrival in 2004. Since 2004, 229 residents have been infected with the virus, 8 of which have lost their lives due to the disease.

In addition to birds and humans, horses are also affected by WNV. Due to the high mortality rate of horses that contract the disease, owners are encouraged to make sure their horses are kept current with their WNV vaccinations.

Individuals can reduce their risk of mosquito-borne disease by following these prevention tips:

- Avoid spending time outside when mosquitoes are active, especially at dusk and dawn

- If you must be outdoors when mosquitoes are active, wear long pants, and long-sleeved shirts, socks and shoes

- Before going outdoors, apply insect repellent containing DEET, Picaridin, IR3535 or oil of lemon eucalyptus according to label instructions

- Make sure that doors and windows have tight fitting screens. Repair or replace screens that have tears or holes

- Eliminate all standing water on your property that can support mosquito-breeding

- Report standing water to Butte County Mosquito and Vector Control District

- Contact Butte County Mosquito and Vector Control District if there is a significant mosquito problem where you live, work, and/or play

The public is encouraged to become part of the state’s monitoring effort for WNV by reporting any dead birds that may have been dead for less than 48 hours. Please call 1-877-968-2473 to report dead birds that may be accepted for testing, or visit the CDHS website, Individuals should take note of the location and condition of the bird before calling for further instructions. While there is no evidence that people can get the virus from handling live or dead birds, individuals should not attempt to catch or handle the birds.

The District requests any and all assistance by area residents to report any suspected mosquito- breeding sites and/or any mosquito activity. Reports can be made by phone at 530-533-6038 or 530- 342-7350 or website at

For more information call the Butte County Mosquito and Vector Control District at 530-533-6038 or 530-342-7350 Monday through Thursday from 6:00AM to 4:30PM.