Less-deadly bird flu found in Giles County
KNOXVILLE - A flock of chickens at a commercial poultry breeding farm in Giles County, in Middle Tennessee, has tested positive for low pathogenic avian influenza, the state confirmed Tuesday.
Low pathogenic avian influenza is considered less serious than the high pathogenic avian influenza found last week in a flock at a Lincoln County grower. Chickens and turkeys with low pathogenic avian influenza may not even show signs of the virus, while high pathogenic avian influenza is usually fatal for domesticated poultry.
Neither is a threat to the food supply, and no affected animals entered the food chain in either case, the state said. Outbreaks carry a very low risk of human illness; however, “out of an abundance of caution,” the state is monitoring the health of workers who worked at either farm or had contact with birds there.
The company that operates the Giles County facility is not the same company associated with the one in Lincoln County, and officials said they didn’t believe one premise sickened the other.
The Giles County outbreak was discovered March 6 through routine tested, and confirmed by state and federal laboratories.
“This is why we test and monitor for avian influenza,” State Veterinarian Dr. Charles Hatcher said. “When routine testing showed a problem at this facility, the operators immediately took action and notified our lab. That fast response is critical to stopping the spread of this virus.”
As a precaution, Hatcher said, the affected flock was euthanized and buried and the facility quarantined. The state also quarantined domesticated poultry within a 6.2 mile-radius and are testing and monitoring those birds, none of which have tested positive for avian influenza or shown signs of illness. The Lincoln County site also remains quarantined, with birds being tested and monitored, though none has tested positive or appears sick.
Though the Lincoln County outbreak was Tennessee’s first instance of high pathogenic avian influenza, the state saw some low pathogenic avian influenza outbreaks in 2009. The main difference in the two types of “bird flu” is that LPAI may affect birds very little, while HPAI kills them. There was an outbreak of HPAI in January 2016 in Indiana, and a series of outbreaks in 2015 in the Midwest.
Both types of the virus occur naturally in wild birds, who carry the virus without getting sick. Wild birds can transmit avian influenza to domesticated birds in both commercial operations and backyard flocks, said Dr. Lew Strickland, extension veterinarian with the University of Tennessee Institute of Agriculture.
“You could carry (the virus) back to your house, especially on your shoes and clothing,” after visiting a place with droppings from waterfowl, who are especially prone to carry it, Strickland said. He recommended chicken owners who have been around wild birds or other poultry change or disinfect their footwear before interacting with their own flock. He also said chicken owners should keep feed spills at a minimum and move water close to the coop, to discourage wild birds from coming in.
Both the Giles County LPAI and the Lincoln County HPAI viruses are an H7N9 strain of avian influenza, which the federal government said is of North American wild bird lineage -- genetically different from the China H7N9 “bird flu” affecting Asia and is genetically distinct.
The state is asking owners of commercial and backyard poultry flocks to closely observe their birds and report a sudden increase in the number of sick birds or bird deaths to the state veterinarian’s office at 615-837-5120 or USDA at 1-866-536-7593.