Poultry producers can find encouragement from the fact that a smaller percentage of wild birds sampled for highly pathogenic avian influenza (HPAI) in the United States so far in 2023 tested positive in the virus than during the same months in 2022.
During the International Avian Influenza Summit on October 16 in Fayetteville, Arkansas, Dr. Julianna Lenoch, United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) national wildlife disease program coordinator, gave an overview of the agency’s wild bird surveillance efforts during the first eight months of the year.
“After coming through kind of a whirlwind in 2022, things do look like and have felt like they’re calming down a little bit,” Lenoch said.
During the first four months of the year, of the 10,257 samples taken from wild birds in 2022, about 7% of those tested positive for HPAI, she explained. And while fewer samples were taken in 2023 at 8,668, a much smaller percentage of those tested positive, roughly translating to about 1.9%.
HPAI infections typically are fewer during the summer months, which was the case both in 2022 and 2023. However, there were substantially fewer from May through August in 2023 than during those same four months in 2022, Lenoch said.
In 2022, 6,741 birds were sampled from May through August and 348, or about 3%, tested positive. However, during that same four-month period of 2023, 7,407 birds were sampled and only ten birds tested positive for HPAI.
Lenoch said several factors could be in play regarding why the percentage of confirmed HPAI cases in wild birds has been so much lower in 2023.
“So, either we were sampling in different regions where the positive birds were, they’re simply not as much avian influenza circulating, or we may be looking at a little bit of a tipping point where some of our wild bird species, at least our dabbling ducks, may be developing some immunity,” she said.
View our continuing coverage of the global avian influenza situation.
