Wednesday, June 19, 2013

Arkansas: Scott County Chicken Positive for H7N7 Avian Flu

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# 7409

 

 

According to the Poultry Federation, Arkansas is the only state that ranks in the top 10 for Broiler Chicken, Turkey, and Egg production. The state is second only to Georgia in producing broiler chickens, and third in the nation in the raising of turkeys.

 

Combined, the value of poultry operations in Arkansas (in 2009) exceeded $3 billion dollars.  Neighboring Oklahoma (Scott county is on the border) produces more than 1/2 billion dollars in poultry each year.

 

All of which makes the discovery yesterday of H7N7 avian flu on a farm in Scott County, a serious economic concern.

 

First, the announcement from Arkansas.gov, then I’ll return with a bit more about this particular strain of avian flu.

 

Scott County Chicken Tests Positive for Avian Flu

 

LITTLE ROCK - The Arkansas Livestock and Poultry Commission received confirmation Tuesday evening that a chicken in a Scott County, Arkansas, chicken house has tested positive for H7N7 Low Pathogenic Avian Influenza.

 

Thirty Livestock and Poultry personnel have quarantined all poultry within a 6.2-mile radius of the growing operation where the infected bird was located. They are coordinating their response and additional testing with the U.S. Department of Agriculture. Only the USDA can officially confirm avian flu cases.

 

Chickens tend to contract avian flu via infected waterfowl or water contaminated by waterfowl. Livestock and Poultry officials believe the recent flooding in Scott County contributed to this transmission.

 

Leaders at the Arkansas Department of Health say the positive test poses no public-health threat.
Avian flu cannot be transmitted to people through the consumption of properly prepared poultry.

 

Reassurances that H7N7 `poses no public health threat’ are perhaps a bit overstated, although the threat to the public is likely extremely low. We have seen sporadic human infection from various H7 strains of avian influenza – including H7N7 – in the past. 

 

The most famous (and most recent) being the H7N9 virus in China, but other – far more common -  H7 strains have been known to infect humans as well.

 

 

The largest known cluster of H7N7 human infection (89 confirmed, 1 fatality) was reported in the Netherlands a decade ago. Details are available in this report from the December 2005 issue of the Eurosurveillance Journal.

 

Human-to-human transmission of avian influenza A/H7N7, The Netherlands, 2003

M Du Ry van Beest Holle, A Meijer, M Koopmans3 CM de Jager, EEHM van de Kamp, B Wilbrink, MAE. Conyn-van Spaendonck, A Bosman

An outbreak of highly pathogenic avian influenza A virus subtype H7N7 began in poultry farms in the Netherlands in 2003. Virus infection was detected by RT-PCR in 86 poultry workers and three household contacts of PCR-positive poultry workers, mainly associated with conjunctivitis.

 

While nearly all of these cases were mild, the impact on the poultry industry was major. More than 30 million birds residing on more than 1,000 farms were culled to control the outbreak.

 

Before the middle of the last decade, there were no uniform requirements to report or  track LPAI (Low Pathogenic Avian Influenza) infections.  That changed in 2006 when the OIE made reporting of LPAI H5 & H7 viruses mandatory.

 

In 2008 we saw a study in  PNAS that suggested the H7 virus might just be inching towards adapting to humans. For more details on that study, you may wish to revisit H7's Coming Out Party and H7 Study Available Online At PNAS.

Last summer in Mexico we saw two mild human cases of H7N3 (see MMWR: Mild H7N3 Infections In Two Poultry Workers - Jalisco, Mexico).

 

But for now, these LPAI viruses are primarily a threat to the poultry industry, and to a far lesser extent, people working in direct contact with infected fowl.

 

Thus far, this Arkansas outbreak is reportedly limited to one poultry farm.  We’ll have to wait to see if testing reveals that this virus has managed to spread beyond this one location.