Spring is Peak Season for Highly Pathogenic Avian Influenza

A low pathogenic (H5) strain of Avian Influenza has been found in a Barron County commercial turkey flock. This comes after a highly pathogenic (H7) strain was found in a Tennessee commercial chicken flock.  A second flock of chickens at a Tennessee commercial poultry operation has tested positive for avian influenza, though officials say it is LPAI, a low pathogenic strain.

According to  Dr. Darlene Konkle, Wisconsin’s Assistant State Veterinarian,the H5N2 strain found in Barron County is not related to the H7 strain found in Tennessee.  High path strains are often fatal for birds, but the low path strain found in our area is not uncommon in poultry flocks and tends to cause few, if any, clinical signs of illness in the birds. Low path avian influenza is similar in severity to the common cold in humans and will eventually clear from the flock without bird loss.

 

Wild waterfowl are considered the natural reservoir of all non or low pathogenic influenza  viruses. They carry influenza viruses, with no apparent harm to their populations. However, in domestic poultry, infection with avian influenza viruses causes two main forms of disease, low and high virulence.

 

Research gathered during the 2015 avian influenza outbreaks suggests that in some cases, migratory birds are directly spreading the avian influenza virus in its highly pathogenic form.  The virus is being carried by waterfowl along an established migratory route that stretches from the Gulf of Mexico Minnesota and Wisconsin. The virus can be transmitted to domestic poultry from migrating waterfowl through droppings that land on farms.

 

One of the risk factors that can aid in the spread of avian influenza is farming activity, primarily on crop farms located up-wind from commercial poultry facilities.  The virus has the ability to be left behind from birds feeding or migrating through a field, and then moving on dust/dirt/residue particles from last year’s harvest, or this year’s spring work.  

 

According to the Minnesota Board of Animal Health and the University of Minnesota studies have shown that influenza viruses can survive cold temperatures in soil environments. Potential contamination of these fields with droppings from migrating birds could serve as a source of avian influenza infection. This study found that actively working (tilling or discing) fields closest to turkey barns within the 14-day reference period was a risk factor. This was potentially due to soil disruption and the creation of airborne particles that could carry the virus.

 

If you farm near a poultry farm, get to know that farmer, and give them notice when you will be in the field.  This will allow them to take steps to mitigate the spread of this devastating disease.

 

The commercial poultry industry provides essential market opportunities for crop farmers in Northwestern Wisconsin.  Because corn and soybean farmers need this market, it is in the best interests of everyone to do what you can to minimize the risk of spreading avian influenza.

 

If you farm adjacent to a turkey farm please contact one of the numbers below as soon as you know you will start your spring field work, please advise the farm name, if known, or field you will be working, the day you will start and finish, and what type of work will be done.

o    Day time contact – Erica @320-231-2304 or Shellie @320-231-2069

o    Night or weekend – Steve @507-304-0527

If you are working fields and you see dead migratory birds or unusually heavy bird activity, also contact one of the numbers above with that information.