Since early 2022, countries around the world have felt the impacts of a highly pathogenic avian influenza (HPAI) outbreak that has threatened wild bird populations and decimated domestic poultry flocks on an unprecedented scale. In the United States, HPAI has been confirmed in over 300 commercial and 500 backyard flocks across 47 states. This has led to the “depopulation” (mass killing) of nearly 59 million birds, the majority of whom have been egg-laying hens.
Pursuant to the Animal Health Protection Act (AHPA), animal disease response in the United States is overseen by the US Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS), in coordination with state and tribal animal health officials. In the event of an HPAI outbreak, the USDA’s primary control and eradication strategy to combat disease spread is “stamping out,” which refers to the mass depopulation of clinically infected and “in-contact susceptible” birds. In practice, this means that if one infection is confirmed in a flock, every single bird at that location will be killed—even if that means killing millions of potentially uninfected birds.
In addition to overseeing disease response, the USDA provides indemnity payments and compensation to producers for the loss of birds and eggs and for certain costs associated with depopulation, disposal, and other virus elimination activities. By June 2023, the federal government had spent an estimated $793 million on HPAI response activities for the current outbreak and had allocated an additional $502 million on preparation for potential infections in the future. These estimates bring the total cost of the current outbreak to well over $1.2 billion, exceeding the estimated $950 million spent on response and preparedness activities and indemnity payments resulting from the 2014–2015 HPAI outbreak—previously the worst animal health disease incident in US history.
Under federal avian influenza compensation regulations finalized in 2018, producers are eligible for HPAI-related payments if they have an audited biosecurity plan in place that is being implemented at the time of disease detection. While biosecurity planning is critical to reducing the risk of disease introduction, it fails to address a primary method of controlling spread once HPAI is detected: the rapid killing of animals exposed to the disease.
To address this shortcoming, AWI petitioned APHIS to amend its regulations to require that producers have in place audited emergency response plans—including strategies to humanely depopulate animals—before they can receive taxpayer-backed compensation for birds killed as a result of HPAI. The goal of this action is to incentivize better preparation to help curb the use of a particularly horrific method of depopulation used at alarming rates during the current outbreak: “ventilation shutdown plus” (VSD+).
VSD+ involves turning off the airflow in a barn and ratcheting up the heat to above 104 degrees, leaving trapped birds to die from heatstroke over several hours. VSD+ likely causes extreme suffering and is therefore not recognized as an acceptable method of killing animals by the World Organisation for Animal Health—the leading international authority on the health and welfare of animals. Nevertheless, VSD+ has been used widely in the United States, triggering public outcry and prompting 3,500 veterinary professionals to go on record to oppose its use. According to an AWI analysis of USDA records, between February 2022 and March 2023, at least 44.9 million birds—nearly 77 percent of the commercial birds impacted in the United States—were killed using VSD+ alone or in combination with other methods.
By comparison, the primary methods for killing birds during the 2014–2015 HPAI outbreak were water-based foam and carbon dioxide (CO2) gassing. Following that outbreak, the USDA evaluated response activities to determine how best to improve response in the future. In doing so, the department recognized that there were depopulation delays that may have contributed to increased spread of the disease, particularly on operations with hundreds of thousands or millions of egg-laying hens. As such, the department established a policy that depopulations should occur within 24 to 48 hours of a presumptive positive case of the virus. It also sanctioned the use of VSD+ as a method of last resort, to be used only when other, more humane alternatives are not available.
AWI’s analysis of USDA records indicates that operations with large flocks (at least 100,000 birds) were much more likely to employ VSD+ as a mass-killing method. Even with the widespread use of VSD+ in such situations, however, the USDA’s depopulation timeline was not met in a majority of cases. Of the 37 large flock depopulation events that involved VSD+, nearly two-thirds took at least three days to complete. In the most extreme cases, in which at least 1 million birds were involved, depopulation took more than two weeks.
It is clear based on the evidence that the larger the operation, the greater the logistical challenges to conducting depopulations in a manner that meets the USDA’s 24- to 48-hour goal. Thus far, however, the USDA has declined to limit the size of operations. Absent such limits, better preparation is imperative—indeed, the only real option if depopulations are to be conducted within the designated time frame and without resorting to VSD+.
AWI’s petition calls on APHIS to make such preparation mandatory. Specifically, it asks APHIS to require producers—as a condition for receiving HPAI-related payments—to have audited emergency action plans that prioritize the use of more humane methods of depopulation. These plans should include detailed descriptions of procedures to (1) depopulate flocks within 24 to 48 hours in a manner that rapidly renders individual animals unconscious, (2) avoid the use of methods such as VSD+ and others categorized by the American Veterinary Medical Association as “permitted under constrained circumstances,” and (3) minimize pain and distress from catching, handling, and confining birds during depopulation.
While the threat of HPAI transmission remains, cases are down significantly since the peak of the outbreak in 2022. Ideally, the USDA would use this window as an opportunity to perform a comprehensive evaluation of response activities to best determine how to control the virus more effectively and humanely. AWI’s petition offers the most logical starting point.
Take Action: Visit AWI’s Action Center to urge the USDA to disincentivize the use of VSD+ in depopulations.