Avian influenza has hit the American egg and turkey industries hard in the last few months with over 45 million chickens and turkeys killed. Several backyard flocks have been affected, and consumer pocket books may be hit soon as well.
Avian influenza is caused by a very tricky virus and there are many different types known as strains. The different viruses are identified by their surface projections referred to as H and N. There are 16 different types of H’s and 9 types of N’s, making for a lot of possible combinations. To complicate things, even with the same H and N designation, the viruses can be classified as low path (LPAI) or high path (HPAI). The designation of LPAI or HPAI refers to the ability of the virus to kill birds. With the LPAI viruses the number of birds that die can be very low. In the case of HPAI types, however, mortality can reach 100% within a matter of days. The problem with the LPAI viruses is that they can easily change and become HPAI. The types of viruses of most concern are the H5’s and H7’s. We are currently dealing with H5N2, H5N8 and H5N1 HPAI strains. The current HPAI outbreak was first detected in western Canada and later detected in northern Washington State in December of 2014. Since then it has been detected in 15 states and has affected 212 farms. Iowa and Minnesota turkey and egg farms have been hit the hardest.
The avian influenza virus is believed to have been brought in by migratory waterfowl (ducks and geese). Waterfowl can carry the virus without getting sick. They shed the virus in their manure, infecting other birds. The HPAI virus has been detected in three of the four North American Flyways – Pacific, Central and Mississippi. At the moment there is no effective vaccine available for HPAI.
Anyone keeping poultry flocks, especially those with waterfowl, needs to be concerned about HPAI. While the majority of the American flocks affected have come from commercial operations, several backyard flocks have been infected as well. Most of these had mixed flocks which included ducks or geese. If you are showing birds, you should be aware that several states, even some without cases of HPAI, have banned poultry shows. So check with your local county extension agent to see if your state has been effected.
To protect your flock: don’t attract wild birds by putting out bird feeders near your flocks; don’t introduce adult birds purchased from swap meets or flea markets; restrict access to your flocks; keep your work cloths and equipment clean; don’t borrow lawn and garden equipment tools or poultry supplies from other bird owners; and be on the alert for warning signs of avian influenza. The warning signs include sneezing, coughing, nasal discharge, watery or green diarrhea, and purple discoloration of the combs, wattles and legs.
When the migratory waterfowl begin in the fall there is a greater chance that avian influenza will be detected along all four flyways. Small flock owners should discourage migratory birds from roosting on their farms. Eliminate feed sources and discourage birds through sound devices. This fall will require producers to be very diligent about hunting and being in the woods so as to not track back the virus to their farms.
To date there is no evidence that the current HPAI viruses that are infecting poultry flocks in the U.S. can infect humans. While it is not believed that the virus is transmitted through poultry meat and eggs, no products from infected flocks are entering the human food chain.
The main effect will be on the price of eggs and turkeys. The HPAI has devastated the egg and turkey flocks and it will take many months for the infected facilities to come back into full production. The result may be a shortage of eggs and turkeys resulting in a major rise in the price of both. To date, meat chicken flocks have not been affected.
Article written by Jacquie Jacob, University of Kentucky, firstname.lastname@example.org