#USA. #Update: #Genetic Sequencing Results for #Wisconsin Dairy #Herd Detection of Highly Pathogenic Avian #Influenza #H5N1 (#USDA, Dec. 20 '25): Clade 2.3.4.4b genotype D1.1

 

WASHINGTON, D.C., December 19, 2025

On December 14, 2025, USDA’s Animal and Plant Health Inspection Service (APHIS) announced the first detection of highly pathogenic avian influenza (HPAI) in a dairy herd in Wisconsin. 

On December 17, the National Veterinary Services Laboratories (NVSL) completed whole genome sequencing and confirmed that the virus is H5N1 clade 2.3.4.4b genotype D1.1. 

Analysis indicates that this detection is a new spillover event from wildlife into dairy cattle, separate from previous events.

Key Points

-- Most detections in U.S. dairy herds have resulted from movements linked to the original spillover event that occurred in the Texas Panhandle in late 2023, involving the B3.13 strain.

-- In early 2025, through the National Milk Testing Strategy, USDA detected two spillover events in Nevada and Arizona dairy herds. Both were identified early, and no further herd infections occurred through animal movements. These events involved the D1.1 strain.

-- The Wisconsin herd, also detected through the National Milk Testing Strategy, represents a new, separate spillover event and involves the D1.1 strain. At this time, no additional dairy herds have been identified as infected in association with this event.

Public Health and Food Safety

-- This detection does not pose a risk to consumer health or affect the safety of the commercial milk supply. 

-- Pasteurization effectively inactivates HPAI virus, and milk from affected animals is diverted or destroyed to prevent entry into the food supply. 

-- The Centers for Disease Control and Prevention (CDC) continues to consider the risk to the public to be low.

The Importance of Biosecurity

-- USDA remains committed to working with state partners to monitor, investigate, and mitigate the spread of HPAI in livestock. 

-- The detection does not change USDA’s HPAI eradication strategy. Biosecurity is still key to mitigating the risk of disease introduction or spread between premises.

APHIS recommends enhanced biosecurity measures for all dairy farms. Producers should immediately report any livestock with clinical signs, or any unusual sick or dead wildlife, to their state veterinarian.

Source: 

Link: https://www.aphis.usda.gov/news/agency-announcements/update-genetic-sequencing-results-wisconsin-dairy-herd-detection-highly

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#USA, #USDA: APHIS Updates #Policy to Enhance #Surveillance of #Turkey #Flocks in Highly Pathogenic Avian #Influenza Affected States

WASHINGTON, January 17, 2025—As part of its ongoing, multi-faceted efforts to combat the spread of highly pathogenic avian influenza (HPAI), USDA’s Animal and Plant Health Inspection Service (APHIS) today is updating its policy for pre-slaughter surveillance to enhance testing of turkey flocks in affected states. 

In late December 2024, APHIS became aware of a genetic link between turkeys potentially infected with HPAI H5N1, virus detected in raw pet food, and an infected household cat.

Out of an abundance of caution, and to remove a potential avenue for ongoing disease spread as well as to bolster consumer and trading partner confidence, APHIS collaborated with state animal health officials and the poultry industry to update its guidance for existing pre-slaughter surveillance steps to further ensure that affected poultry does not enter the food system. APHIS will continue to report confirmed HPAI detections to the World Organisation for Animal Health and on the APHIS website (more information below).

These updates include implementing isolation with clinical monitoring and premovement testing 72 hours prior to sending to slaughter, for turkey premises outside control areas in HPAI-affected states. 

Specifically, APHIS will be piloting this enhanced pre-slaughter surveillance, starting with turkey premises greater than 500 birds in Minnesota and South Dakota, based on current and historical HPAI detections of commercial turkey premises in these states. These states were selected because of genetic linkages to virus from infected cats and because of the high percentage of cases in turkeys in those states. APHIS will continue to evaluate progress of the outbreak and may update this policy, if needed, to include additional states.

USDA consistently operates on a science-based, step-by-step approach, informed by what it learns about this virus through its everyday work and research and surveillance efforts. APHIS will continue to update its guidance for pre-slaughter surveillance schemes as USDA continues to follow the science on HPAI.

In May 2024, USDA announced the transfer of $824 million from the Commodity Credit Corporation (CCC) to APHIS to directly support H5N1 response efforts. This funding supports anticipated diagnostics; field response activities; pre-movement testing requirements; other necessary surveillance and control activities, including surveillance in wildlife; the Agricultural Research Service’s (ARS) work in developing vaccines for HPAI in cattle, turkeys, pigs, and goats; and food safety studies carried out by ARS and the Food Safety and Inspection Service (FSIS).

USDA remains confident in the safety of the food supply. FSIS, APHIS, and ARS have completed multiple studies to confirm that poultry and eggs that are properly prepared and cooked are safe to eat. Additionally, to verify the safety of the meat supply, these agencies have completed three separate beef safety studies related to avian influenza in meat from dairy cattle.

APHIS continues to work closely with state animal health officials on surveillance efforts to look for the virus in commercial, backyard, and wild birds. We also continue to encourage all bird owners to practice strong biosecurity—that means reducing opportunities for wildlife to spread the virus to their birds and preventing the spread of the virus from one premises to another. APHIS will continue to publicly post poultry detections on its dashboard. USDA also makes genetic sequences from the U.S. H5N1 clade 2.3.4.4b influenza virus available on GISAID (the Global Initiative on Sharing Avian Influenza Data) and the National Center for Biotechnology Information (NCBI) Sequence Read Archive (use search term “WGS of H5N1”).

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Source: US Department of Agriculture, https://www.aphis.usda.gov/news/agency-announcements/aphis-updates-policy-enhance-surveillance-turkey-flocks-highly-pathogenic

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#USDA Confirms Highly Pathogenic Avian #H5N1 #Influenza in Backyard #Poultry Flock in #PuertoRico

WASHINGTON, January 13, 2025 – The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic avian influenza (HPAI) in a backyard poultry flock in Puerto Rico.  

This is the first case of HPAI in domestic birds in Puerto Rico during this outbreak, which began in February 2022.

Samples from the flock were tested and confirmed at the APHIS National Veterinary Services Laboratories in Ames, Iowa.

APHIS is working closely with animal health officials in Puerto Rico on a joint incident response and will provide appropriate support as requested. 

According to the U.S. Centers for Disease Control and Prevention (CDC), the public health risk associated with these avian influenza detections in birds remains low.  As a reminder, the proper handling and cooking of all poultry and eggs to an internal temperature of 165˚F is recommended as a general food safety precaution.

As part of existing avian influenza response plans, APHIS and the Puerto Rico Department of Agriculture are conducting additional surveillance and testing in areas around the affected flock. The United States has the strongest AI surveillance program in the world, and USDA is working with its partners to actively look for the disease in commercial poultry operations, live bird markets and in migratory wild bird populations. 

Anyone involved with poultry production from the small backyard to the large commercial producer should review their biosecurity activities to assure the health of their birds. Visit APHIS’ Defend the Flock Resource Center for materials about biosecurity, including videos, checklists, and a toolkit.

USDA will report these findings to the World Organisation for Animal Health (WOAH) as well as international trading partners. USDA also continues to communicate with trading partners to encourage adherence to WOAH standards and minimize trade impacts. WOAH trade guidelines call on countries to base trade restrictions on sound science and, whenever possible, limit restrictions to those animals and animal products within a defined region that pose a risk of spreading disease of concern. WOAH trade guidelines also call on member countries to not impose bans on the international trade of poultry commodities in response to notifications in non-poultry.

All cases in commercial and backyard flocks are listed on the APHIS website.

In addition to practicing good biosecurity, all bird owners should prevent contact between their birds and wild birds and report sick birds or unusual bird deaths to State/Federal officials, either through their state veterinarian or through APHIS’ toll-free number at 1-866-536-7593. APHIS urges producers to consider bringing birds indoors, when possible, to further prevent exposures. The Animal Health Protection Act authorizes APHIS to provide indemnity payments to producers for birds and eggs that must be depopulated during a disease response. APHIS also provides compensation for disposal activities and virus elimination activities. Additional information on biosecurity for backyard flocks can be found on APHIS’ Defend the Flock webpage.

Source: US Department of Agriculture, https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-highly-pathogenic-avian-influenza-backyard-poultry-flock

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#USA, #USDA Confirms Highly Pathogenic Avian #Influenza in Backyard Non-Poultry #Flock in #Louisiana

 {Excerpt}

WASHINGTON, December 16, 2024 – The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic avian influenza (HPAI) in a non-commercial backyard flock (non-poultry) in Bossier Parish, Louisiana.  This is the first case of HPAI in domestic birds in Louisiana during this outbreak, which began in February 2022.

Samples from the flock were tested at the Louisiana Animal Disease Diagnostic Laboratory, part of the National Animal Health Laboratory Network, and confirmed at the APHIS National Veterinary Services Laboratories in Ames, Iowa.

APHIS is working closely with state animal health officials in Louisiana on a joint incident response and will provide appropriate support as requested. 

According to the U.S. Centers for Disease Control and Prevention (CDC), the public health risk associated with these avian influenza detections in birds remains low.  As a reminder, the proper handling and cooking of all poultry and eggs to an internal temperature of 165 ˚F is recommended as a general food safety precaution.

As part of existing avian influenza response plans, Federal and State partners are working jointly on additional surveillance and testing in areas around the affected flock. The United States has the strongest AI surveillance program in the world, and USDA is working with its partners to actively look for the disease in commercial poultry operations, live bird markets and in migratory wild bird populations. 

Anyone involved with poultry production from the small backyard to the large commercial producer should review their biosecurity activities to assure the health of their birds. Visit APHIS’ Defend the Flock Resource Center for materials about biosecurity, including videos, checklists, and a toolkit.

USDA will report these findings to the World Organisation for Animal Health (WOAH) as well as international trading partners. USDA also continues to communicate with trading partners to encourage adherence to WOAH standards and minimize trade impacts. WOAH trade guidelines call on countries to base trade restrictions on sound science and, whenever possible, limit restrictions to those animals and animal products within a defined region that pose a risk of spreading disease of concern. WOAH trade guidelines also call on member countries to not impose bans on the international trade of poultry commodities in response to notifications in non-poultry.

APHIS announces the first case of HPAI in commercial and backyard flocks detected in a State but does not announce subsequent detections in the State. All cases in commercial and backyard flocks are listed on the APHIS website.

In addition to practicing good biosecurity, all bird owners should prevent contact between their birds and wild birds and report sick birds or unusual bird deaths to State/Federal officials, either through their state veterinarian or through APHIS’ toll-free number at 1-866-536-7593. APHIS urges producers to consider bringing birds indoors when possible to further prevent exposures. The Animal Health Protection Act authorizes APHIS to provide indemnity payments to producers for birds and eggs that must be depopulated during a disease response. APHIS also provides compensation for disposal activities and virus elimination activities. Additional information on biosecurity for backyard flocks can be found on APHIS’ Defend the Flock webpage.

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Source: USDA, https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-highly-pathogenic-avian-influenza-backyard-non-poultry-1 

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