US's wild bird H5N1 monitoring expands beyond Alaska

Aug 10, 2006 (CIDRAP News) – US agriculture and interior secretaries announced yesterday that their departments are expanding wild bird monitoring for H5N1 avian influenza beyond Alaska in partnerships with the lower 48 states, Hawaii, and other Pacific islands.

"Because we cannot control wild birds, our best protection is an early warning system, and this move to test thousands more wild birds throughout the country will help us to quickly identify, respond to, and control the virus if it arrives in the United States," said US Department of Agriculture (USDA) secretary Mike Johanns in a USDA–Department of Interior (DOI) press release yesterday.

Scientists are not certain what role migratory birds play in transmitting the H5N1 virus.

DOI secretary Dirk Kempthorne said joint federal and state testing programs will be important this fall when birds now nesting in Alaska and Canada begin migrating south through the continental United States.

President Bush allocated $29 million in his 2006 fiscal year avian influenza supplemental package to cover the cost of implementing the wild bird monitoring component of the National Strategy for Pandemic Influenza. Of the $17 million the UDSA received, $4 million has gone to states to expand wild bird monitoring. The remainder funds USDA sampling efforts, purchase of sampling kits, and analysis of bird and environmental samples.

Of the $12 million that went to the DOI, about $2.4 million has gone to state agencies and other agencies for collecting wild bird samples. The rest of the DOI's allocation will fund DOI's sampling and analysis activities and a data management system for state-federal wild bird sampling efforts.

Surveillance status in Alaska
A surveillance program between the DOI and the State of Alaska has been under way since the summer of 2005. United States monitoring efforts began in Alaska because it is the first US stopover for birds from Asia and other continents where the H5N1 virus is present.

In April, samples from Alaska began arriving for testing at the US Geological Survey's National Wildlife Health Center (NWHC) in Madison, Wis., center biologist Paul Slota told CIDRAP News. "We've screened about 7,000 samples from Alaska. We're on target with the number of samples we needed, so we're off to a good start. Next, we'll be working on samples from the lower 48 states," he said.

Besides screening, the extra resources provided by the federal-state partnership have allowed the NWHC to do more mortality investigations than they could have done otherwise, he said. Screening has identified a fair number of influenza viruses, but none were H5N1, Slota said. Samples positive for H5 influenza are sent to the USDA's National Veterinary Services Laboratory (NVSL) in Ames, Iowa, to determine if they are H5N1. "The lab-to-lab relationship is going very well," he said.

Wild bird monitoring goals
A wild bird monitoring plan drawn up by several groups including the USDA, DOI, International Association of Fish and Wildlife Agencies, National Association of Public Health Veterinarians, and the State of Alaska, is part of the National Strategy for Pandemic Influenza, according to a March press release from the USDA, DOI, and Department of Health and Human Services.

The monitoring plan outlines five strategies for early detection of the H5N1 virus in wild migratory birds:

  • Investigation of disease outbreaks in wild birds
  • Expanded monitoring of live wild birds
  • Monitoring of hunter-killed birds
  • Use of sentinel animals, such as backyard poultry flocks
  • Environmental sampling of water and bird feces

The goal of the USDA-DOI wild bird surveillance plan is to collect 75,000 to 100,000 samples from birds and 50,000 environmental samples. Since 1998 the USDA and the State of Alaska have tested more than 12,000 birds in Alaska, and since 2000 the USDA and the University of Georgia have tested almost 4,000 birds in the Atlantic flyway.

Sampling locations in each state will depend on weather and habitat conditions during bird migration periods, the USDA-DOI press release noted. State and interagency groups will pinpoint sampling locations as migration occurs; likely locations include areas where large groups of birds congregate, such as public lands, private lands with property owner approval, and local areas such as ponds and city parks.

According to an article on the testing plan from the Oregon Department of Fish and Wildlife (ODFW), 11,000 samples from live birds will be screened by the NWHC. The rest will be tested at labs certified by the USDA. Samples that test positive will be sent to the NVSL to determine if H5N1 is present.

Western states launch testing
Oregon and Washington are two of the states in the Pacific flyway, which is the focus of the next round of wild migratory bird screening.

State and federal wildlife biologists will be testing wild birds in Oregon this summer and fall, said a Jun 19 press release from the ODFW. Wildlife authorities will collect samples from several species that are most likely to have been in contact with birds from Asia this summer in the Arctic. Oregon's detection plan will involve collecting about 4,000 samples from migratory shorebirds and waterfowl including pintails, mallards, green-winged teals, geese, and tundra swans.

Live bird sampling began on Sauvie Island, in northwest Oregon near the Columbia River, in late June and will continue through September in six other wildlife management areas. Hunter-harvested birds will be sampled at check stations during hunting season, which runs from September through December. Fecal samples will be collected from June through January from such waterfowl gathering areas as wetlands, urban parks, and golf courses.

In Washington, wildlife biologists began testing 2,500 wild birds in July, focusing on those most likely to have interacted with Asian migratory birds this summer, according to a Jun 13 press release from the Washington Department of Fish and Wildlife (WDFW). The first areas tested were northern Puget Sound and coastal estuaries. Waterfowl testing will focus on pintails and mallards and when possible will include wigeons, green-winged teals, shovelers, and sea ducks. Shorebird testing will target Western sandpipers and dunlin, and when possible will include red knots and ruddy turnstones.

The WDFW estimates that about 1 million geese, 12 million ducks, and 150,000 swans pass through the Pacific flyway each year, beginning in August, on their return from the Arctic. In addition, hundreds of thousands of autumn-migrating shorebirds arrive in Washington between July and October.

See also:

Aug 9 USDA-DOI press release expanding wild migratory bird testing beyond Alaska

Jun 19 ODFW press release on bird testing efforts for avian flu

Jun 13 WDFW press release on avian influenza surveillance plan

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