Talking turkey: How bird flu outbreaks are playing out

A deadly strain of bird flu has reached the Midwest, killing or requiring hundreds of thousands of turkeys to be euthanized. Some questions and answers about the outbreak:

WHAT KIND OF FLU IS THIS, EXACTLY?

H5N2 is a highly contagious virus that kills commercial poultry quickly once it gets into a barn. It can spread via an infected bird's droppings or nasal discharges—yes, can sneeze. But the risk to the public is considered low, and infected are kept out of the food supply.

WHERE IS THIS TURNING UP, AND IN WHAT KINDS OF BIRDS?

Minnesota has been hit harder than any other state, but it's not clear why. The virus has caused outbreaks at eight turkey farms in central and western Minnesota since late February, as well as farms in the Mississippi and Central flyways in Missouri (2) South Dakota (1), Kansas (1) and Arkansas (1). Nearly all the losses have been at big commercial turkey farms. But this strain of bird flu can be just as deadly to chickens. The Kansas outbreak involved a backyard flock of chickens and ducks. H5N2 and other highly pathogenic strains have also been found since late last year among wild birds, backyard flocks and commercial farms in some western states and British Columbia.

AREN'T MOST COMMERCIAL POULTRY BARNS SHUT TIGHT TO KEEP DISEASES OUT?

They are. Poultry farms with good biosecurity strictly limit who's allowed in. Workers often have to shower on their way in and out, wear protective coveralls and step in disinfectant to kill viruses on their boots. Equipment coming in and out is typically sanitized. Trucks entering and leaving a farm might get their tires scrubbed. But the system doesn't always work. Experts say it requires everyone to do everything right all the time. Plus rodents and that sneak into a barn can bring in the virus.

SO WHAT HAPPENS TO THESE TURKEYS WHEN BIRD FLU ARRIVES?

They die, and quickly. The first symptom farm workers notice may be a rapid spike in sudden deaths. Less severe symptoms can be similar to colds and flu in humans, or a flock turning quiet. Vaccines have been used around the world to protect flocks against various strains ahead of time, but this strain is new to the U.S. Once an infection is confirmed at a farm, all surviving birds on the property are typically killed to prevent it from spreading. These flocks are usually killed by pumping a water-based foam into the barn, following guidelines from the U.S. Department of Agriculture endorsed as humane by the American Veterinary Medical Association. The foam suffocates the birds within minutes.

OH. SO WHAT DO THEY DO WITH ALL THESE DEAD BIRDS?

They compost them—usually right in the same barn where they died. It sounds gross, but composting is a widely used and approved method throughout the poultry industry to dispose of birds that die in the usual course of business on a farm—and those that die in disease outbreaks. Studies show that properly done, the heat generated by composting is enough to kill flu viruses and other pathogens commonly present in poultry such as salmonella. The compost then can be safely spread as fertilizer.

DO THESE OUTBREAKS WIPE OUT AFFECTED FARMERS?

An outbreak that kills tens of thousands of birds certainly can cost a farm dearly. The government doesn't compensate producers for birds that die of the disease itself, but it does reimburse them for birds that have to be euthanized as a precaution. That gives farmers an incentive to report suspected outbreaks and deal with them swiftly. Often the birds themselves belong to a big poultry company such as Jennie-O Turkey Store, Cargill or Butterball but are being raised by contract growers. And a barn can be returned to production within a few months, once it's been thoroughly cleaned out and disinfected.

WHY DOES MINNESOTA HAVE SO MANY TURKEYS?

Minnesota is the top turkey state in the U.S. It produces around 46 million turkeys each year worth about $750 million, and exports around 8 percent of its production. Turkey farms have become clustered over the decades around processing plants and cheap sources of feed, and Minnesota has plenty of both. Jennie-O is based in prime turkey territory in western Minnesota, and Minnesota is also leading corn and soybean producer.

SO DOES THIS MEAN I'LL BE PAYING MORE FOR TURKEY?

Probably not. While Minnesota alone has lost around 373,000 birds from this outbreak, and the toll nationwide is over 500,000, that's just a sliver of U.S. turkey production—235 million birds in 2014. If anything, the loss of export markets because of these outbreaks may put downward pressure on prices because that turkey will have to be sold domestically. And don't worry about Thanksgiving. Turkey prices around the holidays often have nothing to do with the costs of production. Retailers often sell turkeys at a loss just to draw in customers who'll stock up on stuffing mix, cranberries, sweet potatoes, pies and other traditional favorites.

© 2015 The Associated Press. All rights reserved.

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