UPDATED: Now includes APHIS Report (see bottom)
There’s not a lot of information available yet, but the USDA’s APHIS website is now showing that a flock of mixed poultry in Whitley County, Indiana (just west of Ft. Wayne) has tested positive for the HPAI H5N8 virus.
This not only adds another state to the list, this is the farthest east we’ve seen HPAI H5N8, and the first appearance in the Mississippi Flyway. .
Previously, we’ve seen H5N8 in a small number of poultry flocks in California (2) and Oregon (1), and in wild birds collected from WA, CA, UT, ID, and NV – all part of the Pacific Flyway. Of the 60 wild birds sampled to date (05/05/15), 1/3rd (n=20) have tested positive for H5N8, while the rest have had HPAI H5N2.
HPAI H5N8 presumably arrived via migratory birds in the Pacific Northwest last fall, and quickly reassorted with North American avian viruses and produced a very hearty hybrid; the H5N2 virus which has spread rapidly across half the nation.
Both viruses are capable of being carried by wild and migratory birds, both can inflict heavy damage to the poultry industry, and both could potentially reassort again to produce even more hybrid viruses. Exactly why H5N2 has spread faster, and farther, than H5N8 isn’t really known.
We will probably see additional updates from APHIS, and from some of the more heavily impacted states, later today.
* * * UPDATED * * *
APHIS has now posted the following statement on their website:
Published: May 11, 2015
CDC considers the risk to people from these HPAI H5 infections in wild birds, backyard flocks and commercial poultry, to be low
WASHINGTON, May 11, 2015 -- The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic H5N8 avian influenza (HPAI) in a backyard mixed-poultry flock in Whitley County, Indiana. While there have been multiple detections of HPAI H5N2 in the Mississippi flyway, this is the first finding of HPAI H5N8 in the Mississippi flyway, which previously had only been confirmed in the Pacific flyway. CDC considers the risk to people from these HPAI H5 infections in wild birds, backyard flocks and commercial poultry, to be low. No human infections with the virus have been detected at this time.
Samples from the flock, which experienced increased mortality, were tested at the Indiana Animal Disease Diagnostic Laboratory and the APHIS National Veterinary Services Laboratories in Ames, Iowa confirmed the findings. APHIS is working closely with the Indiana State Board of Animal Health to respond to the finding. State officials quarantined the affected premises and birds on the property will be depopulated to prevent the spread of the disease.