The presence of highly pathogenic avian influenza (HPAI) was confirmed in commercial poultry or upland gamebird flocks in 21 U.S. states in 2023.
That compares to 27 states where HPAI was confirmed in commercial operations in 2022.
For the second year in a row, Minnesota and South Dakota were the two states with the most flocks infected with HPAI. However, the two states flipped positions in terms of how they ranked among the states with the most flocks affected.
According to data from the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS), here is a breakdown of how each state compared to the others:
1. South Dakota
South Dakota had more HPAI infections in commercial operations than any other state in 2023. For the year, 36 commercial flocks were affected. The state’s first case of 2023 was confirmed on March 22 and the final case was confirmed on December 30. The affected flocks involved meat turkeys, turkey breeder hens, turkey breeder replacement hens and upland gamebirds. Despite having HPAI’s presence confirmed in more commercial flocks than any other state in 2023, South Dakota still had fewer flock infections that year than it did in 2022, when 61 flocks were affected.
2. Minnesota
Minnesota saw a substantial year-over-year decline in commercial flock infections. After having 81 flocks affected in 2022 – more flocks than any other state – Minnesota ranks second for 2023 with 34 flocks struck by the virus. The state was able to avoid any HPAI infections in commercial poultry until the first case was confirmed on October 11, and those cases continued through December 27. Affected flocks involved commercial meat turkeys, turkey breeder hens, breeder toms, egg layers and breeder hens of an unspecified species.
3. California
California was the only other state to see a double-digit number of flock infections. It ranked third among the states with 22 flocks hit by HPAI. That number actually increased, as the state had 15 confirmed flock infections in 2022, when California ranked sixth in terms of flocks affected. California had more diversity concerning the type of flocks affected in 2023, as those involved table egg layers, table egg layer pullets, meat turkeys, meat ducks, duck breeders and broilers. The state’s first HPAI case in a commercial operation was confirmed on February 6 and the final one was confirmed on December 23. However, new cases of HPAI have already been confirmed in California in 2024.
4. Pennsylvania
Pennsylvania had the fourth most flock infections in 2023, with seven. This was a drop for Pennsylvania, which with 25 infected flocks in 2022 had more commercial operations affected than all states except Minnesota and South Dakota. All but one of the state’s HPAI cases occurred in February and March, until the presence of the virus was again confirmed in Pennsylvania commercial upland gamebird operation on December 27. Other affected flocks involved meat turkeys, meat ducks, duck breeders and broilers.
5. Ohio and Iowa
After only having one commercial poultry flock affected by HPAI in 2022, six flocks were affected in Ohio in 2023. These involved meat turkeys, table egg layers and table egg layer pullets. All of the state’s cases for the year were confirmed in November and December.
Like Ohio, Iowa also had six commercial flocks affected by HPAI in 2023. This is a meaningful drop from the 24 flock infections in Iowa in 2022. Four of Iowa’s affected flocks were commercial meat turkeys and the other two involved commercial table egg layers. The first case for the year was confirmed on January 25 and the final was confirmed on November 28.
7. Kansas and Wisconsin
After having only one flock affected by HPAI in 2022, Kansas had five in 2023. The first three occurred during the first two months of the year and involved commercial upland gamebirds. Then, in December, two commercial layer flocks were affected. Also, the state has already had one commercial flock affected in 2024.
Wisconsin, like Kansas, also had five flocks affected by HPAI in 2024. All five of those involved commercial meat turkeys, and all five occurred during the final two months of the year. Also like Kansas, Wisconsin has already had its first commercial flock infection of 2024.
9. Arkansas
Arkansas was the state with the ninth most flock infections in 2023 after finishing 2022 with only one. There were four cases in 2023, and they all occurred between October 31 and December 7. These cases involved broilers, broiler breeder pullets and commercial meat turkeys.
10. North Dakota
With three flocks affected by HPAI in 2023, North Dakota ranked 10th among states for the most flocks lost. All three were commercial meat turkey flocks. The first case was confirmed in April while the other two were confirmed in November. In 2022, North Dakota had five commercial flocks affected.
States that lost two flocks
The following states lost two commercial flocks to HPAI in 2023: Alabama, Virginia, Oregon, Michigan, Utah and Missouri. The most significant year-over-year change involved Utah, which lost 19 commercial flocks in 2022. Missouri also saw a drop in cases, with eight flocks affected in 2022. However, Alabama, Virginia and Oregon had no flocks affected in 2022, and Michigan had only one.
States that lost one flock
The following states lost one commercial flock to HPAI in 2023: Maryland, Tennessee, Illinois, Georgia and Mississippi. In 2022, Maryland had five flocks affected, while Tennessee and Mississippi lost three flocks and one flock, respectively. No commercial flocks were struck by HPAI in Illinois or Georgia in 2022.
A similar article about how states ranked in terms of HPAI bird losses appears on WATTPoultry.com.
To learn more about HPAI cases in commercial poultry flocks in the United States, Mexico and Canada, see an interactive map on WATTPoultry.com.
View our continuing coverage of the global avian influenza situation.
