West Nile Virus

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What is the West Nile Virus and what should I do about it?

Stanislaus County West Nile Virus Hotline: (209) 558-8425

What can you do to protect yourself?

West Nile virus is transmitted by mosquito bites. It cannot be transmitted from person to person.
Avoid outdoor activity from dusk to dawn.
Dress appropriately during peak mosquito hours (wear long sleeves).
Use mosquito repellents containing DEET.
Drain pools of water and remove objects that can hold stagnant water (old tires).

Avoid Mosquito Bites to Avoid Infection

SOURCE: The Centers for Disease Control and Prevention

West Nile virus is spread by the bite of an infected mosquito, and can infect people, horses, many types of birds, and some other animals.

Most people who become infected with West Nile virus will have either no symptoms or only mild ones. On rare occasions, infection can result in a severe and sometimes fatal illness known as West Nile encephalitis (an inflammation of the brain). The risk of severe disease is higher for persons 50 years of age and older.

Protect Yourself from Mosquito Bites

Avoid mosquito bites by applying insect repellent when spending time outdoors. Use repellent safely. Always read and follow product instructions. Human illness from West Nile virus is rare, even in areas where the virus has been reported. The chance that any one person is going to become ill from a mosquito bite is low.

You can further reduce your chances of becoming ill by protecting yourself from mosquito bites. To avoid mosquito bites, you can limit the number of places available for mosquitos to lay their eggs by eliminating standing water sources from around your home.

Apply insect repellent containing the active ingredient DEET, Oil of Lemon Eucalyptus, or Picaridin when outdoors, according to label instructions.

Use care in applying repellent to small children, and don't put repellent on their hands because it may get into their mouth or eyes and cause irritation. Whenever you use any insecticide or insect repellent, be sure to read and follow the product directions. For more information see Using Insect Repellent Safely from the EPA. Wearing long-sleeved clothes and long pants treated with repellent will further reduce your risk, as will staying indoors during peak mosquito feeding hours (dusk until dawn).

Check to see if there is an organized mosquito control program in your area. If no program exists, work with your local government officials to establish a program. The American Mosquito Control Association can provide advice, and their book Organization for Mosquito Control is a useful reference.

When possible, wear long-sleeves, long pants and socks when outdoors. Mosquitoes may bite through thin clothing, so spraying clothes with repellent containing permethrin or DEET will give extra protection. Don't apply repellents containing permethrin directly to skin. Do not spray repellent containing DEET on the skin under your clothing.

Be Aware of Peak Mosquito Hours

Mosquito Proof Your Home

Drain Standing Water
Mosquitoes lay their eggs in standing water. Limit the number of places around your home for mosquitoes to breed by getting rid of items that hold water.

Install or Repair Screens
Some mosquitoes like to come indoors. Keep them outside by having well-fitting screens on both windows and doors.

Offer to help neighbors whose screens might be in bad shape.

How to Report Dead Birds

Dead birds in an area may mean that West Nile virus is circulating between the birds and the mosquitoes in that area. Over 230 species of birds are known to have been infected with West Nile virus. Although birds, particularly crows and jays, infected with WN virus can die or become ill, most infected birds do survive.

The State of California has created a hotline, 1-877-WNV BIRD(1-877-968-2473), to report birds that have been dead for less than 48 hours to have them picked up for testing for West Nile virus. You can also send an electronic notice to the state. The bird should show no signs of decomposition or maggot infestation. Birds such as crows, ravens, magpies, jays or hawks are the primary animals of concern. You can also watch a video on Reporting a Dead Bird on the WestNile.ca.gov website.

Call the state hotline at 1-877-WNV-BIRD (1-877-968-2473) or visit westnile.ca.gov.
There is no evidence that West Nile virus can be acquired from handling dead birds, but it is recommend you do not handle the bird with your bare hands.
Place the bird in two plastic bags (double bag the bird) using gloves, a shovel, or by turning the bags inside out and collecting the bird.
If you have found a dead bird on your property, and it has not been collected by 5 p.m. on the day of your report, you may safely dispose of it in your trash.

Guidelines for Dead Bird Reporting and Disposal

If you have found a dead bird on your property, please contact the California Department of Health Services by calling toll free 1-877-WNV-BIRD (1-877-968-2473) to report the dead bird, or you may submit the information via the web site westnile.ca.gov.

If you are instructed to dispose of the dead bird, or if the dead bird has not been picked up by five o’clock (5 p.m.) on the day it was reported, please follow these guidelines:

Avoid touching the dead bird with your bare hands. Ensure that your clothing does not come in contact with the dead bird or any blood, secretions or feces from the dead bird.
Use gloves or multiple heavy-duty plastic bags to pick up the dead bird.
Grasp the dead bird with your hand inside the plastic bags. Turn the plastic bags inside-out over the dead bird so the dead bird is now inside the plastic bags and your hands are on the outside of the plastic bags. Be sure that the beak or claws do not puncture the bags.
Tightly seal the two bags.
Dispose of the "double-bagged" bird carcass by placing it in a trash container. Ensure that the trash container is secure from children and animals while awaiting pickup from your refuse company.
WASH YOUR HANDS thoroughly with warm water and soap after disposal. If you wore gloves to dispose of the dead bird, wash your gloved hands and then wash your bare hands thoroughly after you have removed the gloves.

There is currently no evidence that the West Nile Virus can be transmitted to humans that have taken precautions when handling dead birds.

Stanislaus County West Nile Virus Recorded Hotline: (209) 558-8425

Mosquito Control Programs

Check with local health authorities to see if there is an organized mosquito control program in your area. If no program exists, work with your local government officials to establish a program. The American Mosquito Control Association can provide advice, and their book Organization for Mosquito Control is a useful reference.

More questions about mosquito control? A source for information about pesticides and repellents is the National Pesticide Information Center , which also operates a toll-free information line: 1-800-858-7378 (check their Web site for hours).

Clean Up

Mosquito breeding sites can be anywhere. Neighborhood clean up days can be organized by civic or youth organizations to pick up containers from vacant lots and parks, and to encourage people to keep their yards free of standing water.

Mosquitoes don't care about fences, so it's important to control breeding sites throughout the neighborhood.

Find out more about local prevention efforts. Find state and local West Nile virus information and contacts on the CDC website.

Source: Centers for Disease Control and Prevention

Route of West Nile Virus

The most likely route of WNV infection to humans is through the bite of an infected mosquito. WNV may also be transmitted by organ transplantation, blood transfusion, or possibly breast milk. Transplacental (mother-to-fetus) infection has occurred. Laboratory-acquired infection has also been documented. Turkey breeder farm workers have been infected with WNV. The mode of transmission to these farm workers is unknown.

Who is at risk?

Most human WNV infections cause either no symptoms or a mild flu-like illness. The most severely affected patients may develop an inflammation of the brain, or the membranes of the brain or spinal cord, or both, called encephalitis, meningitis, or meningoencephalitis, respectively. These severe cases may be fatal. Persons over age 50 are at higher risk of severe illness following infection.

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