Texas, Gonzales, Ducks destroyed after virus found: State poultry group buys flock in order to have the fowl eliminated

[Sally Furniss]

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Ducks destroyed after virus found: State poultry group buys flock in order to have the fowl eliminated

By GREG LITTLE/publisher@gonzalesinquirer.com

Around 3,500 ducks in Gonzales County had to be destroyed earlier this year by an order from state officials.

The ducks, owned by Gonzales resident Steve Hendershot, were located on County Road 238 north of Gonzales.

The Gonzales Inquirer has been working on this story for more than a month. State officials at first said they were unaware of the issue and refused any comment. However, after a phone call from the office of Rep. Edmund Kuempel, R-Seguin, officials released the entire story about what happened.

State officials said the flock had to be destroyed because of positive tests for a bird virus.

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Andy Schwartz, state epidemiologist for the Texas Veterinary Medical Diagnostic Laboratory (TVMDL), said last week the situation began last November during random testing of the duck flock.

Schwartz said new rules in the state require random testing of flocks when birds from those flocks are sold at live bird markets in Texas. Such was the case with the ducks in Gonzales County.

He said state officials did a "routine sampling" and those samples were sent to the diagnostic laboratory at Texas A&M University in College Station.

Schwartz said when the tests were conducted, "it came up positive" for possible Avian flu virus. However, he also said that "any influenza will trip the test."

Because of the positive test, the samples were then sent to the National Veterinary Services facility in Ames, Iowa.

"They repeated the same result and found the matrix positive," said Schwartz.

At that time, he said they "attempted to isolate the virus."

Schwartz said more samples were then tested. They were "particularly concerned" about two strains which "could cause an outbreak in the poultry industry."

Those two strains are H5 and H7, he said, and the samples tested negative for those two strains.

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http://www.gonzalesinquirer.com/articles/2010/03/15/news/news01.txt

[Sally Furniss]

2004 H5N2 in Poultry in Texas

2004 story

H5N2 in Poultry in Texas

In February 2004, an outbreak of highly pathogenic avian influenza (HPAI) A (H5N2) was detected through routine surveillance and reported in a flock of 7,000 chickens in Gonzales County in south-central Texas. This was the first outbreak of HPAI in the United States in 20 years. Chickens from this flock were sent to two live bird markets in the Houston area. The affected flock and live bird markets were quarantined, depopulated (poultry were culled), and the premises were cleaned and disinfected. Three distinct zones, with varying intensities of surveillance, were established around the index flock for surveillance. All samples taken from the surveillance zones tested negative for avian influenza. The quarantine of the affected flock and premises was lifted on March 26. On April 1, the U.S. Department of Agriculture (USDA) informed the Office International des Epizooties (OIE) that HPAI in Gonzales County, Texas, had been completely eradicated.
The H5N2 strain in Texas was a different influenza virus from the H5N1 virus reported in parts of Asia (which also is highly pathogenic among poultry). The Texas H5N2 and the Asian H5N1 outbreaks were not related. The H5N1 outbreaks among poultry in Asia have been associated with human illness in Thailand and Vietnam, but no human illnesses occurred from the H5N2 virus in Texas.
The potential risk of human infection with an H5N2 avian virus similar to that reported in Texas is likely to be very low, but such risk does exist. Risk depends on the degree of exposure to infected birds and areas or objects contaminated by the virus and the capacity (which can vary considerably) of the virus to infect people. CDC issued interim guidance documents recommending measures to prevent possible human infection with avian influenza viruses during avian influenza outbreaks in the United States. These interim guidance documents are applicable to the Texas outbreak, as well as to other avian influenza outbreaks that may occur in the United States. These documents are available on CDC?s Web site and include Interim Recommendations for Persons with Possible Exposure to Avian Influenza During Outbreaks Among Poultry in the United States and Interim Guidance for Protection of Persons Involved in U.S. Avian Influenza Outbreak Disease Control and Eradication Activities.


http://www.maphtc.iupui.edu/html/CD_Training/Avian_Influenza_and_other_pandemic_influenza/outbreaknorthamerica.html


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15 March 2004
Scientific Tests Led to Bird Flu Upgrade
SAN ANTONIO - Last week's outbreak of avian influenza in South Texas looked at first like a mild form of the disease, like those on the East Coast a few weeks earlier. But just a couple of days later, the news had turned grim ? the strain of bird flu found on a chicken farm in Gonzales County was "highly pathogenic", meaning it was both highly contagious and lethal to poultry. That report from the U.S. Department of Agriculture quickly set many wheels in motion. A USDA command post was created in Gonzales and the search for more infected birds intensified, large chicken processors rushed to reassure their domestic consumers and foreign markets locked their doors to poultry shipments from America.

Just what happened between Friday and Monday to spur such a frenzy? The answer is a government lab in Iowa simply did more sophisticated testing. And there's another round of results to come that will tell animal scientists even more about the Gonzales outbreak, the first highly pathogenic cases in the United States in two decades. "There's no easy way to say whether its high-pathogenic or low-pathogenic until you do the confirmatory testing," said Jim Rogers, a USDA spokesman in Washington. State veterinarian Bob Hillman on Friday said that the Gonzales bird flu was a low-risk variety that would not cause much damage to chicken growers in the county, which is one of the major poultry areas in Texas. Hillman didn't elaborate then on why he thought the avian flu was low-pathogenic, but he said Wednesday that his office made its judgment based on how many chickens on the infected farm were dying from the disease. ?While we did have a significant death loss in the birds," he said, "it was not an extremely high death loss which would be typically characteristic of a high-pathogenic avian influenza virus."

Hillman said 250 to 300 broilers died before the disease was first diagnosed in a local lab, and on Saturday the remaining 6,600 birds on the farm were euthanized and buried. At the same time, scientists were doing genetic tests on infected chickens at the National Veterinary Services Laboratory in Ames, Iowa. The second round of testing was routine because the strain of avian flu in Gonzales was known as H5N2, based on the proteins found in the virus. The H5 and H7 subtypes can be either low-pathogenic or high-pathogenic, so genetic sequencing is used to gauge virulence. During the 1983-84 outbreak in Pennsylvania and Virginia, an H5N2 strain that was not treated morphed from low to high pathogenicity. On Monday morning, Ron DeHaven, the USDA's chief veterinarian, announced that the initial low-risk determination was wrong ? this bird flu was indeed dangerous. At the same time, he praised Texas officials for their fast action to kill all of the chickens on the Gonzales farm, just in case.

"By quickly identifying and depopulating this flock, they quickly and effectively reduced the chances for spread of infection, which both from an animal standpoint and any potential human health standpoint, that's very important," DeHaven said. No other bird flu cases had been found in the area as of Wednesday, Hillman said. Officials are searching a 10-mile radius of the infected farm.

The H5N2 subtype is not the same as the avian flu strain that has killed at least 22 people in Southeast Asia. The Gonzales form is not known to have any ill effects on humans, according to the federal Centers for Disease Control and Prevention. Results from a third test ? this one long considered the gold standard ? are expected at the beginning of March. The Gonzales virus has been isolated and injected into eight young chickens at the Iowa lab, and after 10 days, scientists will count how many of the birds have died. If the number is at least six, or 75 percent of the sample, the flu will be considered highly pathogenic. "What happens in the birds is actually more important than what you read biochemically (in the genetic test)," said Alex Bermudez, an avian pathologist at the University of Missouri. But what happens if fewer than six die? Hillman says he doesn't think the outbreak would once again be classified as low-pathogenic because of conflicting results from the various tests.

T.A. Badger, Associated Press Writer
26 February 2004

http://www.vetscite.org/publish/items/001721/index.html