Bird flu sampling: So far so good

Baton Rouge — The Louisiana Department of Wildlife and Fisheries (LDWF) recently completed sampling efforts for the 2007-08 Avian Influence Surveillance Program ahead of schedule. LDWF has never had a positive avian flu test in any of their samplings to date and avian flu has never been reported in migratory birds in North America.

LDWF sampled 200 wood ducks, 211 blue-winged teal, 208 northern pintails and 164 shorebirds during the past biological year that started in August 2007. Louisiana’s sampling goals during the biological year called for collecting 750 samples from wild migratory birds.

“Hunter-harvested birds accounted for the highest percentage of samples collected,” said Nan Huff, LDWF’s wildlife disease coordinator. “Live wild bird sampling was coordinated with the LDWF’s duck banding program.”

The surveillance program, which reflects a cooperative relationship between LDWF and the U.S. Department of Agriculture (USDA), is designed to detect and identify subtypes of avian influenza viruses in wild bird populations.

Wild birds in the Pacific, Central, Mississippi and Atlantic flyways are sampled in all 50 U.S. states and select U.S. territories.

‘Zero Findings’

“Louisiana’s plan targets those species most likely to mingle with birds from Asia on breeding or migration routes and transport the virus down the Mississippi Flyway to Louisiana,” Huff said. “Samples from those birds have been analyzed for presence of the Highly Pathogenic Avian Influenza (HPAI) H5N1 virus. We are happy to report that we have had zero findings of avian flu in any of our samples.”

The immediate benefit of the surveillance program is to provide timely disease monitoring. Information is also generated that will enhance future wild bird surveillance campaigns and help mitigate possible impacts to domestic poultry production facilities.

Avian influenza is an infection caused by the avian influenza virus. In nature, the virus occurs in wild aquatic birds, such as ducks and shore birds. The highly contagious virus has persisted in the intestines of these birds for millions of years; however, the virus typically does not make the birds sick. On the other hand, the virus can infect and kill many domesticated birds, including chickens, ducks and turkeys.

The virus is shed from the infected birds through saliva, nasal secretions and feces. Infections occur when domesticated fowl come into contact with infected water, dirt or wild waterfowl.

Pigs are Players

Pigs have been shown to be a natural host for the virus and can pass the flu to humans. Pigs are an important step in the virus as both the avian influenza virus and the human influenza virus can infect the pig at the same time. The two viruses can also exchange genes and produce a newly designed virus, which may be more or less severe than the original viruses.

The virus does not normally spread from birds to humans. However, in 1997, a virulent strain of avian flu, called HPAI H5N1, was discovered that directly infected humans from domesticated birds in Asia. As of May 5, 2006, HPAI H5N1 was responsible for the deaths of 114 of the 206 people infected by the virus since 2003. Virtually all of the infected people had contracted the virus via direct contact with infected poultry.

Since wild birds are a reservoir for the virus, which has already spread across Asia, Europe, and parts of Africa, concerns about the avian influenza virus spreading to North America have been raised.

Wild ‘Carriers’

Migrating waterfowl carry the H5N1 virus, often without themselves becoming sick. The HPAI H5N1 strain is causing concern because it is also a threat to domestic poultry. For these reasons, LDWF has been actively participating in the Avian Influenza Surveillance Program to monitor the potential occurrence of Avian Influenza in North America.

LDWF is receiving more and more calls regarding the impacts of avian flu on waterfowl hunting seasons and the safety of handling, preparing and consuming harvested birds.

“At this time, HPAI H5N1 has not been found in North America and there is no known case where avian flu has been passed from wild birds to humans,” Huff said. “Consequently, the risk of hunters being infected is very low. However, we cannot guarantee there is no risk, and it would be irresponsible to make predictions.”

LDWF would like to again remind everyone, especially hunters, to follow these common-sense guidelines:

•As a general rule, people should enjoy wildlife from a distance to both minimize disturbance and eliminate exposure to any wildlife-borne health concerns.

•Do not handle wild birds, especially if sick or dead.

•Do not handle or eat sick birds.

•Use disposable gloves while cleaning game.

•Do not eat, drink or smoke while handling or cleaning birds.

•Thoroughly clean hands, knives and cleaning surface after cleaning game.

•Make sure all game is thoroughly cooked (about 165 degrees).