MADISON — A dangerous bird-flu strain that already has hit numerous turkey farms in the Midwest has now been identified in a Jefferson County chicken flock, marking the first case of the virus in a commercial chicken farm in the U.S. and its first appearance in Wisconsin, the U.S. Department of Agriculture said Monday.
Authorities stressed there was no risk to public health and no danger to the food supply from the highly pathogenic H5N2 strain, which was first detected in the region in Minnesota early last month.
No human cases have been found in the U.S. But as a precaution, the Wisconsin Department of Health Services is reaching out to workers who may have been exposed. Surveillance and testing also are underway at nearby farms.
Animal health officials have long said the virus is dangerous to all commercial poultry. The only surprise of it turning up in chickens is that it took so long, said Raechelle Cline, a spokeswoman for Wisconsin’s agriculture department.
The USDA said tests confirmed that a flock of about 200,000 chickens at an egg-laying facility in Jefferson County, has been infected.
The owner of the egg-laying facility found a dead bird about a week ago and sent it to a laboratory in Missouri for testing. After the initial diagnosis was avian flu, it was sent to another lab in Ames, Iowa, where the diagnosis was confirmed, Cline said.
About 20,000 chickens already have died from the disease at the Jefferson County facility, and the remaining 180,000 will be killed to help prevent the disease from spreading, according to the Wisconsin Department of Agriculture, Trade and Consumer Protection.
The unnamed egg-laying facility in Jefferson County housed all its chickens inside buildings, Cline said.
Humans aren’t susceptible because influenza viruses have spread from birds to humans in only extremely rare cases, virtually all in people who worked with birds and lived in countries that don’t have strong management systems, said UW-Madison animal sciences professor Mark Cook, an expert on avian health.
The food supply is not in danger because birds with the virus show symptoms quickly and are either sick or dead before they lay eggs or are slaughtered, Cook added.
He noted that the most likely scenario for the Jefferson County facility’s infection was indirect contact, which is why poultry experts are most concerned about people who own backyard flocks of three or four chickens transmitting the disease, Cook said.
“If you don’t have really tight biosecurity, there’s a chance this could walk into your barn,” Cook said “Any bird that is not in confinement, they can be exposed and someone can pick it up.”
He said somebody can have it in their home and can walk into a chicken complex and (an outbreak can occur).
“That’s why most poultry companies do not allow any of their workers to have backyard flocks, for the fear of bringing something like this in,” Cook said. “It’s why I don’t want anybody in our facility who has backyard flocks.”
Strict protocols are being followed to contain and eliminate the disease, according to Dr. Paul McGraw, Wisconsin state veterinarian.
“The facility was immediately quarantined and neighboring properties with poultry will be notified about the situation. The remaining chickens in the affected flock will be depopulated and will not enter the food supply.”
The Wisconsin Department of Health is working directly with poultry workers at the affected facility to ensure that they are taking the proper precautions.
As a reminder, the proper handling and cooking of poultry and eggs to an internal temperature of 165 ˚F kills bacteria and viruses.
In addition, as a precaution, the Wisconsin Department of Health Services is reaching out to monitor workers who might have been exposed to the virus. DATCP also has been working with the USDA.
These virus strains can travel in wild birds without them appearing sick. People should avoid contact with sick/dead poultry or wildlife. If contact occurs, wash your hands with soap and water and change clothing before having any contact with healthy domestic poultry and birds.
“Now that we have a confirmation, it’s in a poultry owner’s best interest to take precautions to minimize the effect that this strain of avian influenza will have on their flock,” McGraw says.
He recommends the following six steps for protecting birds from avian influenza:
• Keep your distance — Restrict access to your property and keep your birds away from other birds.
• Keep it clean — Wash your hands thoroughly before and after working with your birds. Clean and disinfect equipment.
• Don’t haul disease home — Buy birds from reputable sources and keep new birds separated for at least 30 days.
• Don’t borrow disease — Do not share equipment or supplies with neighbors or other bird owners. If you must borrow, disinfect it first.
• Know the warning signs — Early detection can help prevent the spread of the disease. Check your birds frequently. If you find a sick or dead bird, don’t touch it.
• Report sick birds — Don’t wait. If your birds are sick or dying, call DATCP at 1-800-572-8981.
USDA will include the confirmation information in routine updates to the World Organization for Animal Health (OIE), and will notify international trading partners of this finding as appropriate. OIE trade guidelines call on countries to base trade restrictions on sound science and, whenever possible, limit restrictions to those animals and animal products within a defined region that pose a risk of spreading disease of concern.
The disease has cost turkey producers more than 1.2 million birds across the Midwest — including more than 900,000 in Minnesota, the nation’s No. 1 turkey-producing state. Still, that only accounts for about 0.5 percent of the 235 million turkeys produced nationally in 2014. The disease also has struck farms in Arkansas, Missouri, Kansas, South Dakota and North Dakota since early March. The Minnesota Turkey Growers Association on Monday estimated the dollar value of turkeys lost in the state at $15.7 million.
Although the affected Wisconsin farm produces eggs, the broiler chicken industry, which produces chickens for meat, also has been bracing for the virus since it was detected in the Pacific Northwest late last year, said Tom Super, spokesman for the National Chicken Council. He noted that the chicken industry is much larger than the turkey industry, with Americans eating about 83 pounds of chickens annually compared with about 16 pounds of turkey.
“We’re certainly remaining on double-heightened alert,” he said, noting that most broiler production is in southeastern and mid-Atlantic states where the virus hasn’t appeared.
Scientists suspect the disease is being spread by migratory waterfowl, but that hasn’t been proven. They’re also trying to determine how the disease has been getting inside poultry barns despite strict biosecurity measures designed to keep it out.
H5N2 turned up on several chicken farms in British Columbia, Canada, late last year, and this month in Ontario. It also has been detected in some backyard flocks, but the Wisconsin case is the first detected in a U.S. commercial chicken operation, said Joelle Hayden, a USDA spokeswoman.
Wisconsin, which typically ranks around 18th among U.S. states in chicken production, exported poultry products worth $4.7 million in 2014.
No human cases have been found in the U.S.
Following USDA protocols, surveillance and testing procedures are under way at properties near the affected facilities, to ensure the virus has not spread.
Commercial poultry operations are big on biosecurity, and scientists still are trying to figure out how the bird flu makes it to such operations.
At S & R Egg Farm, a third-generation family business in Whitewater, workers wear rubber boots and walk through a special water bath before they go into the barns, said Dan Gorecki, chief financial officer.
When workers move between units in the same building, they walk over another disinfecting pad of dry powder.
How worried are they about it?
"I guess you're always worried," said Gorecki.
About 40 countries have blocked imports of turkey or chicken products to varying degrees from the affected states, but many of those countries weren’t big customers. And some major importers, such as Mexico, are scaling back their bans to specific countries.
The outbreaks have cost the industry a small fraction of its annual production, and they’re not expected to affect retail prices much.