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Five million layers snuffed as avian flu hitsRembrandt Enterprises down with virus


Rembrandt Enterprises was struck on Friday with avian influenza for the second time in less than seven years.

The Iowa Department of Agriculture and Land Stewardship announced that avian influenza was detected in “a flock of commercial layer chickens” in Buena Vista County. The infected flock of around 5.3 million birds was Rembrandt’s egg-laying facility with some 20 barns and a processing plant that employs 300 permanent workers and hundreds of temporary workers.

“Depopulation is underway at the infected facility,” said Chloe Carson, a spokesperson for IDALS, over the phone on Friday. Carson confirmed the size of the flock, but declined to specify the exact location of the infection.

Samples from a single barn registered positive in tests conducted by IDALS and the USDA’s Animal Plant Health and Inspection Service in Ames last week. The entire flock of 5.3 million is expected to be destroyed.

The company destroyed its entire flock of 5.6 million laying hens in June 2015, when the disease reached a zenith in Iowa. Rembrandt’s flock represented 18% of the overall number of the 32 million birds that were culled in Iowa in the 2015 outbreak. IDALS reported at the time it would take over a year for the company to restock its barns and fully recover. 

Sheila Hagen, Rembrandt’s vice president of human resources and legal, didn’t respond to a request for comment.

The infection is the second registered in Buena Vista County this month. A barn of around 50,000 turkeys north of Newell was depopulated after the USDA’s Animal Plant Health and Inspection Service detected the virus there. Five detections have been reported in Iowa this month.

IDALS Secretary Mike Naig said last month the department and APHIS learned a number of “lessons” from the outbreak of 2015.

One of the methods that has been updated is how flocks are depopulated. A memo APHIS issued in January permits the use of VSD+, a system in which barn ventilation shuts off; temperatures above 104 degrees are then introduced. The birds die by suffocation.

Carson, the IDALS spokeswoman, confirmed the depopulation method for the 5.3 million birds was VSD+. Other methods, like water-based foaming, were considered ineffective in the circumstance, she said.

Carson declined to specify the extent to which IDALS would rely on VSD+. She said it was a technique that would be evaluated on a case-by-case basis.

VSD+ has been criticized by animal-rights groups as inhumane because suffocation is involved in the euthanization process. But it is considered effective to kill all birds in an infected facility within 24 to 48 hours of a presumed positive test, the USDA said in January.

Research since the outbreak in 2015 has found air ventilation played a critical role in the disease’s spread in the beginning of the outbreak.

A paper published in 2019 in the scientific journal Nature by Yang Zhao, an agricultural engineer and poultry scientist at the University of Tennessee, found the virus could transmit through the air within 24 hours of a flock becoming infected. Ventilation shutdown could be part of a swift response to depopulate, and by extension, prevent the spread through the ambient air, the report suggests.

“Whole-housed thermally-assisted ventilation shutdown depopulation… could be used as a backup plan,” Zhao’s report reads. It is entitled “Airborne transmission may have played a role in the spread of 2015 highly pathogenic avian influenza outbreaks in the United States.”

The six-page memo the USDA issued in January stressed that swift depopulation is crucial to “reduce the quantity of infectious material and eliminate further potential for HPAI transmission.” Hence it is now a priority for all infected flocks to be depopulated within 24 to 48 hours of a detection. Before the 2015 pandemic, it wasn’t a priority, according to the memo.

Officials in Pocahontas and Buena Vista counties applauded IDALS for implementing VSD+ in the two infections that have been detected. Carson declined to confirm whether the state used the technique in its other response, which was later revealed to be a barn of around 50,000 turkeys between Newell and Albert City.

“No more foaming-yay,” reads a memo that circulated between emergency management and county engineers in the counties.

Foaming containing water and carbon dioxide is an alternative euthanization method. Local officials and IDALS considered it inferior to VSD+ because it increases the number of trucks on site and the extent of cleanup, said Pocahontas County Engineer Jack Moellering.

The suffocated birds are composted in the barn and hauled out to a nearby tract for burial, Moellering explained of IDALS depopulation techniques.

“The state believes they’ve improved their procedures,” Moellering said. “The state says their procedure is to keep everything inside the building. Last time around they hired a contractor to clean out buildings. The contractor went around from place to place and brought things with them that were transferred.”

A spokesperson for Clean Harbors Environmental Services, the USDA’s contractor for cleanup during the 2015 outbreak in Iowa, couldn’t be reached for comment.

Buena Vista County Engineer Bret Wilkinson said the aims of the VSD+ method, in addition to the composting and burial on-site, limit the amount of infected birds exposed to the air, which aligns with the research. They also limit traffic through the sites, which were highlighted in a post-mortem of the 2015 outbreak. (The Pocahontas County Board of Supervisors already closed three stretches of roads next to turkey buildings.)

“You kill them, you compost them and then you bury them,” said Wilkinson, whose department closed 520th Street southwest of Albert City earlier this month to assist state and federal officials cull the infected turkey barn. “(The approach) is more advanced than it was last time, we were told. We’ll think about shutting down roads if we have to, just to do our part.”


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