National Wildlife Health Center

...advancing wildlife and ecosystem health

Guidelines for Handling Birds to Prevent Spread of West Nile Virus

The appearance and spread of West Nile virus (WNV) in North America has sparked concern among people in the scientific and public health communities, partly because of the zoonotic nature of this virus. The possibility of acquiring a zoonotic disease from handling wildlife is not new; in fact, a number of diseases are more transmissible to humans while handling infected animals than WNV. Moreover, the majority of people infected with WNV either have very mild disease or are completely unaware of the infection, but the prevalence of WNV in wildlife, domestic animals, and humans throughout North America, makes this disease of particular concern to anyone working with animals. The following guidelines are provided for individuals, particularly wildlife biologists/researchers, that have field contact with wild animals that are proven or potential hosts capable of amplifying and shedding WNV. A list of species found to be positive is available at:

Currently, all birds should be considered at least potential hosts capable of amplifying and shedding WNV.

General Considerations - For people working with wildlife in the field, the primary concern for becoming infected with WNV is through the bite of an infected mosquito. The recommendations presented here are meant to reduce the possibility of direct exposure to a variety of zoonotic diseases. The methods for direct transmission include (but are not limited to):

  1. Inhalation: inhaling air contaminated with virus contained in body fluids; splashing of body fluids from infected animals.
  2. Direct Exposure: contact from infected animals’ body fluids to abrasions, cuts in the skin, or mucous membranes (eyes, mouth).
  3. Puncture Wounds: cuts from contaminated bones, beaks, claws, etc; punctures and cuts from contaminated equipment (needles, scissors, scalpels, etc.)

These general precautions should be taken while handling all wildlife, especially those that appear sick. Handling wild animals can increase the opportunity for exposure to many diseases.

The direct transmission of WNV from infected animal to biologist outside of the laboratory has not yet been documented, but enough is known about the nature of WNV to warrant concern. Fecal material, saliva, and blood are the most likely sources of virus infection from handling an infected animal. If you have been in contact with infected animals or contaminated materials, flush and wash the exposed area with soap and water. If you encounter any of the above-mentioned modes of transmission or if illness develops following suspected exposure, see a physician as soon as you can and advise them of your exposure to wild birds and other wildlife. Symptoms of WNV infection can be found at:

Individuals who may be more susceptible to WNV infection, or more susceptible to disease following infection, should take all possible precautions, including excusing themselves from the work in question. This group of individuals may include those that are immune suppressed for any reason (e.g., steroid therapy, chemotherapy, etc.) and those who have a history of respiratory or other health problems. Individuals should contact their physician if they have specific questions or concerns.

Personal Protective Equipment/Procedures - Depending on the circumstances, some or all of the personal protective measures listed here should be used. Personal protective measures include: using mosquito repellent, wearing mosquito resistant clothing (e.g., long pants, long sleeves, bug jackets, head nets), washing of hands, face, and other exposed skin surfaces, using ‘surgical type’ gloves, wearing coveralls and boots, wearing eye protection or full face shields, and wearing face masks. Measures to reduce exposure to mosquitoes can be found at:

Wildlife-related activities and some personal protective measures


Protective Measures


Wash hands, other exposed surfaces

& Boots

Eye Protection/
Face Shield
Face Mask
Wildlife Survey
Capture & Sample
(aerosol unlikely)
Capture & Sample
(aerosol likely)
Capture & Sample
(sick animal)
Pickup (dead animal)
Pickup (sick animal)

Note: Bracketed bullets [•] indicate that circumstances will dictate the degree of protection necessary. For example, less precaution may be necessary if picking up a single dead or sick small bird, compared to responding to a die-off of many birds, where additional precautions would be recommended. “Wildlife Survey” means those activities where contact with animals is minimal, but the opportunity to be bitten by mosquitoes is great, such as a walking survey for birds or visiting wetlands to count waterfowl. These precautions are suggested for handling birds only. If invasive procedures, such as dissections and necropsies are planned, more precautions, including using a tight-sealed forced-air respirator, are necessary.

Preventing Further Spread of Disease - Additional precautions should be considered in order to prevent the spread of disease while handling sick or dead wild animals. Preventive measures include:

  1. Wearing gloves while handling animals and washing hands between each animal;
  2. Changing gloves or cleaning gloves with a disinfectant between each animal;
  3. Changing needles and syringes between blood collection of different animals;
  4. Wearing different clothing and footwear at each activity site and washing/disinfecting clothing/footwear between sites; and
  5. Cleaning mist nets, traps, cages, and other equipment of fecal material, blood, or other materials between animals and sites.

Some of these precautions appear obvious while others may not. Preventing the spread of disease requires awareness and appropriate behavior, and is based on common sense.

Precaution with insect repellents - Using insect repellent is an effective way to protect yourself from WNV and other diseases spread by mosquitoes. However, certain repellents can cause some harm to some wildlife species, particularly amphibians because they absorb through their skin. Thoroughly wash hands before handling any amphibian.

FIT CoverageContact a member of our Field Investigation Team (FIT) if you have questions about these handling suggestions or other concerns.

  • Western U.S.: Barb Bodenstein, 608-270-2447,
  • Central U.S.: Dr. LeAnn White, 608-270-2491,
  • Eastern U.S.: Dr. Anne Ballmann, 608-270-2445,
  • Hawaii, Pacific Islands: Dr. Thierry Work, 808-792-9520,
  • Nationwide, single animal cases only: Jennifer Buckner, 608-270-2443,

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Page Last Modified: May 19, 2016