The Tennessee state veterinarian confirms that a strain of highly pathogenic avian influenza (HPAI) has sickened a second commercial chicken breeder flock within the existing controlled quarantined zone in Lincoln County, Tenn.
On March 14, samples taken from the flock tested positive for avian influenza. Following federal laboratory confirmation of H7N9 HPAI, officials began depopulation of the affected premises.
This particular strain of avian influenza is the same that affected a commercial chicken flock earlier this month in Lincoln County. The two premises are less than two miles apart. Due to that close proximity, operators at the second premises were closely monitoring and regularly testing poultry for signs of avian influenza. The swift detection enabled immediate response.
“Wild birds can carry this strain of avian influenza.” State Veterinarian Dr. Charles Hatcher said. “Given the close proximity of the two premises, this is not unexpected. We will continue to execute our plan, working quickly to prevent the virus from spreading further.”
On March 4, the first confirmed detection of H7N9 HPAI occurred in a commercial poultry flock in Lincoln County. On March 8, a commercial poultry flock in Giles County tested positive for H7N9 low pathogenic avian influenza (LPAI). Due to the contagious nature of avian influenza and its threat to domesticated poultry, the best way to contain the virus is to depopulate affected flocks and then disinfect affected premises.
Neither HPAI nor LPAI pose a risk to the food supply. No affected animals entered the food chain. Furthermore, the Tennessee Department of Health confirms that the risk of a human becoming ill with avian influenza during poultry illness incidents is very low. This virus is not the same as the China H7N9 virus affecting Asia and is genetically distinct.
The primary difference between LPAI and HPAI is mortality rate in domesticated poultry. A slight change to the viral structure can make a virus deadly for birds. Avian influenza virus strains often occur naturally in wild migratory birds without causing illness in those birds. With LPAI, domesticated chickens and turkeys may show little or no signs of illness. However, HPAI is often fatal for domesticated poultry.
State and federal officials continue to monitor and test poultry located in the areas immediately surrounding the three affected premises. No other flocks have shown signs of illness.
Source: Tennessee Department of Agriculture