Avian Influenza

In 2006, the Colorado Division of Wildlife (CDOW) used multiple survey approaches to monitor wild bird populations for avian influenza (AI) viruses. These programs were developed in response to national concerns over an emerging Asian strain of highly pathogenic AI (HPAI) virus (also termed “H5N1”), and the possibility that migrating wild birds may introduce Asian HPAI into North America.

The CDOW Wildlife Health Program’s (WHP) primary focus was to investigate unusual mortality events of ill/dead wild birds reported across the state of Colorado. WHP staff responded to all calls forwarded by the Colorado Health Education Line for the Public (CO-HELP) line regarding dead birds. Calls were handled using a decision tree developed in conjunction with the Colorado Avian Disease Surveillance Program and Colorado Department of Public Health and Environment staff.

During the month of June 2006, the CDOW obtained cloacal swabs from 2,974 resident Canadian geese (1,319 from Front Range sites, 1,655 from the Western Slope sites). The swabs were submitted for AI screening. Only 3 of 2,974 swabs yielded evidence of low pathogenic AI strains endemic in North American waterfowl; no geese tested positive for HPAI. The prevalence of low pathogenic strains of AI was consistent with historical waterfowl surveillance data. See AI Surveillance Map - June 2006 (pdf).

In July 2006, the CDOW, working with the U.S. Department of Agriculture (USDA), began a surveillance program to detect HPAI virus in wild, apparently healthy birds in Colorado as part of a nationwide surveillance program. This surveillance approach was based on the concern that some wild birds may become infected and shed AI virus for some period before showing outward signs of the disease.

Priority species for sampling in Colorado were selected in coordination with surrounding states, and included waterfowl (dabbling ducks, diving ducks, and geese) and shorebirds that migrate through Colorado. Target sample sizes for wild, apparently healthy birds were 500 for CDOW and 700 for USDA. Target species were based on priority species identified by the Central Flyway Council that were likely to occur in Colorado. Sample size targets for each species were based on its priority status in the Central Flyway plan, and the anticipated ability to find and obtain samples from that species in Colorado.

Initially, 12 waterfowl and 13 shorebird species from the Central Flyway plan were targeted for sampling in Colorado. However, there were concerns that some species (e.g., buff-breasted sandpiper, black-bellied plover) would be extremely difficult to find in Colorado. In addition, our approach allowed sampling of other species of birds that are closely related to target species and occur in the same habitats.

Read the full summary – 2006 Surveillance to Detect Highly Pathogenic AI in Wild Birds in Colorado (pdf)

What is the Division of Wildlife doing about Avian Influenza?

In response to reports of the emerging HPAI H5N1 strain causing deaths in wild birds in Asia, including some migratory species, government agencies are stepping up their efforts to watch for the disease in wild birds in North America.

The Colorado Division of Wildlife will be working with other state and federal wildlife management and animal health agencies as a cooperator in more expansive surveillance efforts planned for improving our understanding about avian influenza viruses in North America.

In addition to surveys specifically targeting avian influenza viruses, the Colorado Division of Wildlife routinely responds to and investigates unusual cases of mortality and disease outbreaks in wild birds and mammals statewide. To report die-offs in wildlife anywhere in Colorado, please contact your local Colorado Division of Wildlife Service Center.

What do hunters need to know about avian influenza?

Based on advice from public health officials, hunters should not be overly concerned about HPAI H5N1 at the present time. As always, however, hunters should take common sense precautions for proper hygiene when handling and preparing game bird carcasses, just as recommended for all game handling. These basic precautions are recommended:

Do not handle birds that are obviously sick or birds found dead. Report die-offs in wildlife anywhere in Colorado to your local Colorado Division of Wildlife Service Center.
Keep your game cool, clean, and dry.
Do not eat, drink, or smoke while dressing game.
Use rubber or disposable gloves when cleaning game.
Wash your hands with soap and water or alcohol wipes after dressing game.
Clean all tools and surfaces immediately afterward; use hot soapy water then disinfect with a 10% chlorine bleach solution.
Cook game meat thoroughly (155-165 degrees Fahrenheit) to kill disease organisms and parasites. Do not eat any raw portions of wild game.

Web Sites

The websites below provide more details as well as additional links to sites with information about avian influenza viruses and HPAI H5N1.

Avian Influenza in Wild Birds:

Information for Hunters:

Public Health Information:

Printable Version of AI Information

For you convience, we have provided a printable version of this information. About Avian Influenza viruses and the HPAI H5N1 strain (pdf).

Last Updated: 6/22/2011 4:32 PM