Highly Pathogenic Avian Influenza Situational Report, May 16, 2022

Is Highly Pathogenic Avian Influenza (HPAI) in the United States over?

No. HPAI continues to impact US domestic and wild birds, and we should be very grateful we’ve not recently had domestic flock cases in Maine, but very cautious to keep it from happening again.

Between this February and last week, approximately 37.7 million poultry were lost due to HPAI per the United States Department of Agriculture (USDA). In commercial flocks, there were losses of almost 30 million US layers and pullets, over 5 million US domestic turkeys (including approximately 150,000 breeders), well over 2 million US broilers (including almost 100,000 broiler breeders), and about 150,000 US domestic ducks (per Eric Gingerich, Association for Veterinarians in Egg Production). While these losses were seen from Maine to Washington state, the fact that last week saw 3 new commercial farms affected in Pennsylvania suggests that our region is definitely not “out of the woods”.

We don’t have a good way of knowing how much HPAI is circulating in the wildlife population, but we can use good common sense and biosecurity to reduce any impact on our domestic flocks, and any public health impacts.  Avian flu may mutate to become pathogenic to people, though so far only one human case has been reported in the US, in a poultry worker:

So, the best practice would be to continue to keep free-range birds within coops or otherwise separate from wild birds (and separate from fields and water bodies where wild birds have been), and to avoid feeding wild birds (to avoid congregating wild birds and spreading the virus, and to keep from attracting wild birds to your domestic flock’s area). It’s hard to say when things will be “back to normal”, but in the meantime, please keep an eye on the Maine Department of Agriculture, Conservation & Forestry (DACF)’s Animal Health, Highly Pathogenic Avian Influenza (HPAI) page and the Avian Influenza, 2022 Confirmations of Highly Pathogenic Avian Influenza in Commercial and Backyard Flocks post (USDA Animal and Plant Health Inspection Service).

As well, you can see where it has occurred in wild birds by visiting the Avian Influenza, 2022 Detections of Highly Pathogenic Avian Influenza in Wild Birds post (USDA Animal and Plant Health Inspection Service), but remember that once it is in a general area/state, it may amplify and spread within the resident wild birds and also domestic flocks.

Submitted by Anne Lichtenwalner, DVM Ph.D., University of Maine Associate Professor of Animal and Veterinary Sciences and Director of the UMaine Veterinary Diagnostic Laboratory.