The current highly pathogenic avian influenza (HPAI) outbreak is outpacing the last outbreak in 2014-2015 in terms of cases.
According to an American Farm Bureau Federation investigation, as of April 7, 2022, there have been 158 cases of HPAI in commercial and backyard flocks in 25 states.
In 2014-2015, there were 232 cases overall of HPAI in domesticated flocks in 15 states which resulted in the depopulation of more than 50.5 million commercial chickens, turkeys and other poultry to limit the spread of the disease.
Flyways
There are four major flyways wild birds use to migrate north and south which contributes to widespread HPAI. In 2014-2015, the Mississippi flyway had 91% of cases detected at commercial flocks, the Central flyway had 8%, the Atlantic flyway had 1% and the Pacific flyway had none.
As of April 2022, the Mississippi flyway has 49% of detections at commercial flocks, the Central flyway has 36%, the Atlantic flyway has 15% and again the Pacific flyway has none.
According to data so far, cases are more evenly spread this year in comparison to 2014-2015 when they were mostly concentrated in the Mississippi flyway.
Commercial layers, pullets, turkeys and broilers
In 2014-2015, there were 50 outbreaks of HPAI in commercial layer flocks which resulted in the death or depopulation of approximately 43 million layer hens and pullets.
In comparison, as of this month, almost 17.9 million layers and 0.83 million pullets have been depopulated, which is 4.6% of the average number of layer hens in the U.S. in 2021 and 0.7% of pullets as of Dec. 1, 2021.
In 2014-2015, there were 160 outbreaks in commercial turkey flocks which resulted in the death or depopulation of approximately 7.4 million turkeys—7.46% of turkeys in the U.S.
In 2022, more than 3.2 million turkeys have been depopulated so far—1.4% of turkeys in the U.S. in 2021.
In 2014-2015, only 0.01% of U.S. broilers died or were depopulated. In 2022, there have been nine outbreaks in commercial broiler flocks resulting in the depopulation of 2.1 million birds—0.02% of U.S. broilers raised in 2020.
Response and losses
After the 2014-2015 outbreak, the U.S. Department of Agriculture revised the National HPAI Surveillance Plan to “determine the areas where HPAIV is located so poultry producers can be alerted and subsequently increase their biosecurity measures to help prevent direct or indirect introduction of HPAIV from wild birds,” according to the revised plan.
An increase in testing and reporting could be one reason why the current outbreak is outpacing the last.
According to the Congressional Research Service, the economy-wide losses caused by the 2014-2015 outbreak were $3.3 billion. There are concerns about what the overall loss will be by the end of this year’s outbreak, especially since detections started about five weeks earlier than the last outbreak.
To learn more about HPAI cases in North American commercial poultry flocks, see an interactive map on WATTPoultry.com.
Read our ongoing coverage of the global avian influenza outbreak.
