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What You Need To Know About Avian Flu

Amy Mayer/IPR file photo
Commercial turkeys, laying hens, and broilers all have been affected by the H5N2 avian influenza currently spreading through the Midwest.

H5N2 has plagued commercial poultry flocks in Iowa and the upper Midwest. So far, the U.S. Department of Agriculture has confirmed 139 cases of this highly pathogenic strain of avian flu nationwide.

Though the virus presents low risk to human health and few food safety concerns, it is devastating to poultry producers. If even a single bird is found infected with the virus, the entire flock must be euthanized so as to contain the disease's spread.

These 139  infected flocks total to more than 32.5  million individual birds. More outbreaks are expected.

  • Is H5N2 dangerous to human health? There are no documented cases of the H5N2 virus in any mammal, including people according to the Centers for Disease Control and Prevention. The CDC says the risk to human health is low and that genetic analysis indicates it is unlikely that H5N2 will spread to humans. 
  • So are eggs, turkey meat and other poultry products OK to eat? Yes. The USDA doesn't allow product from flocks infected with H5N2 to enter the market. If a person ate an egg or meat from a bird with H5N2 by accident, the process of cooking should kill the disease.
  • Will there be a food shortage or price increases? Probably not. If it weren't for bird flu, poultry farmers would be having a decent year due to the low price of grain. So while an avian flu outbreak is devastating for individual producers, consumers likely won't notice a change at the supermarket.
  • Where are the confirmed cases of avian flu? UPDATED (5/12/2015): Business analyst Maro Ibarburu of the Egg Industry Center says prior to avian flu, the egg industry was expanding. Therefore larger supplies and lower prices were expected. Avian flu depleted supplies, so prices will likely go up. However because some countries have banned U.S. poultry imports it's unclear how high prices will rise. Also because 2015 started with more chickens than usual, the price increase may not be too dramatic.

  • How does H5N2 spread? UPDATED (5/12/2015): The USDA says the virus is likely carried through wild birds, perhaps migratory waterfowl. One prevailing theory is poultry become ill after breathing in particles from the feces of wild birds. Check out the map above for daily updates of new H5N2 outbreaks.
  • Where does the virus come from? H5N2 is a strain of avian flu that sprang from another form of avian flu called H5N8. Thomas DeLiberto of the USDA's National Wildlife Research Center says H5N8 probably came from Asia, by migratory birds, and then mixed with North American viruses. The mixing created H5N2, as well as another strain of avian flu called H5N1. While all three strains are highly pathogenic, DeLiberto says researchers are not sure why there have been so many H5N2 outbreaks in Midwest flocks.
  • If only a few birds are sick in a flock, why must the entire flock be euthanized? H5N2 is very contagious, with a high mortality rate. Scientists aren't entirely sure how the virus keeps infecting new flocks. Poultry producers are reportedly taking extensive bio security measures to contain the virus, and yet outbreaks continue. The USDA say eradication is necessary for containment.
  • Is the process of eradication humane? That's a matter of opinion, though the Iowa Department of Agriculture says birds are euthanized as humanely as possible. For turkeys, USDA contractors often cover birds with a suffocating foam mixture of gas and water. Chicken flocks are likely euthanized by being placed in tankers prepared with CO2 gas.
  • Is there any financial help available to producers affected by the virus? The USDA provides an indemnity, or compensation, for euthanized birds as well as some support for the process of composting the birds and cleaning an infected facility. There is no subsidy for birds killed by the virus.
  • How can you tell if a bird has H5N2? The virus has a high mortality rate, so usually poultry farmers first realize something is wrong when birds start dying at a high frequency. For symptoms in an individual bird, it may stop eating and drinking, and become lethargic. In layer hens there will be a drop in egg production. Turkeys are known to exhibit a condition called "torticollis," which is when they twist their necks, almost like stargazing. 
  • Should owners of backyard flocks be concerned? The USDA reports at least dozen backyard flocks have been infected. The USDA recommends that people to isolate their birds, not share tools and keep equipment clean.  
  • Have any non-poultry or waterfowl been infected with H5N2? Captive falcons and a great horned owl have also been infected with the virus.
  • What about a vaccine? Dr. David Swayne, who heads the USDA's Southeast Poultry Research Laboratory, says his lab is in the early stages of developing a potential vaccine. At least one private animal science company called Harrisvaccines in Ames, Iowa is also working on a vaccine. Even if a vaccine is developed, though, it would require a massive amount of labor to inoculate flocks of thousands, if not millions, of birds.
  • What else is being done to combat avian flu?   State and federal agencies are sampling wild birds to track the virus. These H5 viruses are relatively new, so more sampling must be done to understand why poultry farmers in the Upper Midwest are so susceptible to this virus.
  • When will this stop? This virus does best in a cool, damp, overcast climate. Hopefully hot, dry summer days will bring a stop to avian flu outbreaks. Not only does the sun dry out contaminated feces, but ultraviolet light kills the disease. However, the USDA is anticipating another round of outbreaks in the fall.