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Introduction

Personal protective equipment (PPE) is an essential component of efforts to mitigate Influenza A(H5N1) transmission between livestock and humans in high-risk agricultural environments. Human H5N1 infections most often occur after close, prolonged, and unprotected contact with infected birds, dairy cattle, other animals, or contaminated surfaces. However, PPE usage varies across farms and industries, and numerous barriers inhibit PPE adoption in agriculture. PPE can include gowns, gloves, goggles, face shields, head covers, respirators, shoe covers, and surgical masks.

On September 29–30, 2025, the National Academies of Sciences, Engineering, and Medicine’s Board on Health Sciences Policy held a public workshop sponsored by the National Institute for Occupational Safety and Health’s (NIOSH) National Personal Protective Technology Laboratory (NPPTL) to convene industry experts, epidemiologists, veterinarians, public health professionals, producers, researchers, community health workers, community organizers, PPE innovators, and other interested parties to explore PPE needs and best practices to protect workers in high-risk U.S. farm settings and control H5N1 transmission.¹ See Box 1-1 for the formal workshop charge.

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¹ A recording of the full workshop can be found on the event’s webpage: https://www.nationalacademies.org/event/45411_09-2025_personal-protective-equipment-for-influenza-a-h5n1-inhigh-risk-farm-settings-a-workshop (accessed November 17, 2025). The planning committee’s role was limited to planning the workshop, and the Proceedings of a Workshop has been prepared by the workshop rapporteurs as a factual summary of what occurred at the workshop. Statements, recommendations, and opinions expressed are those of individual presenters and participants and are not necessarily endorsed or verified by the National Academies of Sciences, Engineering, and Medicine, and they should not be construed as reflecting any group consensus.

WORKSHOP CHAIR WELCOME AND OPENING REMARKS

Shawn Gibbs, workshop chair and professor and dean of the Texas A&M University School of Public Health, explained that protecting high-risk farmworkers from H5N1 and other potential pathogenic threats simultaneously protects U.S. communities and the nation at large. Noting that the scope of the workshop focuses on PPE, he emphasized that PPE is only one component of the hierarchy of controls, and it is most effective when used in tandem with elimination, substitution, engineering, and administrative measures. Substantial variations across poultry, dairy, and other livestock industries and across regions and production systems warrants tailored approaches, he added. The workshop features broad representation of industries, professions, subject matter, regions, and perspectives to inform customized strategies.

Expressing his gratitude to NIOSH for sponsoring the workshop, Gibbs described the institute as a driver of new knowledge in the field of occupational safety and health and a key influence in transferring that knowledge into practice. As the global gold standard in workplace safety and health, NIOSH ensures a productive workforce that enables growth in the U.S. economy, food supply stability through the agricultural industry, and manufacturing of goods that improve lives, he continued. Gibbs noted that this sponsorship serves as one example of the institute’s many efforts to protect the safety, health, and well-being of American workers and the industries they serve.

NATIONAL INSTITUTE FOR OCCUPATIONAL SAFETY AND HEALTH OPENING REMARKS

Maryann D’Alessandro, director of NIOSH NPPTL, described PPE as part of a larger effort to protect farmworkers and communities from H5N1 and other infectious diseases. When H5N1 first appeared in poultry and dairy herds, the U.S. Centers for Disease Control and Prevention (CDC) acted quickly to assess risks, monitor human exposures, and share protective guidance. This response included rapid development of PPE recommendations to protect frontline farmworkers. Farmworkers—who play an essential role in sustaining a strong food supply—face the highest risks when zoonotic disease threatens spread to humans. Thus, protecting farmworkers signifies protecting families, communities, and national security. D’Alessandro emphasized that guidance alone is insufficient, and PPE is only effective if its use is integrated into the realities of daily farm work. Challenges include PPE access, training gaps on how and when to use PPE, language barriers, and heat stress. She underscored how extreme heat can make PPE very uncomfortable and possibly unsafe. Featuring the

perspectives of farmworkers, employers, and community partners, this workshop sought to inform understanding of farmworker preferences, barriers, and needs related to PPE. This knowledge can then be applied to making PPE as practical, trusted, effective, and scientifically sound as possible, said D’Alessandro.

NATIONAL CENTER FOR IMMUNIZATION AND RESPIRATORY DISEASES OPENING REMARKS

CDR Lizette O. Durand, U. S. Public Health Service, chief veterinary officer at the CDC Influenza Division in the National Center for Immunization and Respiratory Diseases (NCIRD), provided an update on CDC surveillance and monitoring of avian Influenza A(H5N1) viruses humans in the United States. She described how CDC’s process for establishing a public health response begins with the National Response Framework (NRF), a guide for U.S. response to all types of disasters and emergencies. Built on scalable, flexible, and adaptable concepts identified in the National Incident Management System and aligned with key roles and responsibilities, NRF spans five mission areas: prevention, protection, mitigation, response, and recovery. Within NRF, 15 emergency support functions (ESF) provide the structure for coordinating federal interagency support during a response. Durand noted that CDC primarily supports ESF 8—public health and medical support services—by providing subject matter expertise in disease surveillance, patient care, and related activities.

During the coordinated U.S. government response during 2024 and 2025 to the A(H5N1) virus outbreak in dairy cattle, CDC worked closely with the U.S. Department of Agriculture (USDA), the U.S. Food and Drug Administration, and other federal agencies, said Durand. While serving as the lead for human health, CDC priorities included (1) engaging public health and agricultural partners at the state, local, and federal levels; (2) protecting human health by helping states and jurisdictions establish monitoring and testing programs for people working with infected cattle and ensuring these programs had information and resources needed to help prevent infection; (3) conducting epidemiological studies to understand risk and identify ways to prevent additional human cases; and (4) assessing A(H5N1) viruses in people and animals for genetic changes that may indicate viral adaptation and increased transmissibility.

U.S. Centers for Disease Control and Prevention H5N1 Response

Durand offered a brief overview of the current status of A(H5N1) in the United States, reporting 70 confirmed human cases since the beginning of the outbreak in 2024 until July 2, 2025, with no new cases since February

2025 and no known human-to-human transmission. By working closely with state and federal partners, CDC continues to monitor the situation. For example, when a new dairy herd detection occurred in Nebraska, CDC immediately contacted the Nebraska Department of Health and Human Services and began coordinating efforts, as is standard with each new detection in a dairy herd or poultry flock. State health and agriculture departments collaborate to contact farmworkers and initiate monitoring of people exposed to infected cattle. Durand explained that individuals are monitored for 10 days following exposure to A(H5N1) viruses and tested if they develop any signs or symptoms of illness.

In working to characterize isolated viruses, CDC has conducted genetic sequencing of viruses from human cases, when feasible, and identified A(H5) virus clade 2.3.4.4b in those instances, said Durand. She emphasized that this is the same clade detected in dairy cattle and widely circulating among wild birds. Importantly, available information indicates that current diagnostics have the capability to detect this virus. In three influenza specimens from Washington state A(H5N1) cases, CDC identified a change resulting in a slight reduction in susceptibility to oseltamivir, an influenza antiviral medication, in laboratory tests, although this reduction is not expected to affect oseltamivir’s effectiveness in people. Additionally, CDC identified a different change associated with decreased susceptibility to another influenza antiviral medication, baloxavir, however, baloxavir is not currently recommended for treatment or post-exposure prophylaxis of A(H5N1) virus infection. The virus remains closely related to two existing A(H5N1) candidate vaccine viruses, which could be used to produce vaccines against A(H5N1) illness in humans if needed, Durand stated.

Durand emphasized that CDC recommends all people with direct or close exposure to animals infected with A(H5N1) virus should be monitored for 10 days after their last exposure. Symptoms may include fever or feeling feverish, cough, sore throat, runny nose, body aches, headaches, fatigue, eye redness or conjunctivitis, or shortness of breath or difficulty breathing. Less common symptoms include diarrhea, nausea, vomiting, or seizures. CDC recommends to partner organizations and clinicians that anyone with potential exposure who develops signs or symptoms should seek medical care, be tested for influenza, and isolate while awaiting testing results.

State and local health departments are actively monitoring workers on affected farms and facilitating testing and treatment as necessary, said Durand. Several updated CDC guidance documents are available on the appropriate use of PPE to prevent A(H5N1) virus infection in workers. The agency also provides specific guidance for employers and occupational groups at increased risk of exposure to novel Influenza A viruses. She highlighted CDC’s recommendation that farmworkers wear PPE when in close

proximity to dairy cattle, raw milk, other animals, or potentially contaminated surfaces or materials. To communicate this guidance, CDC developed educational materials in English, Spanish, and various Indigenous languages that describe recommended PPE, proper donning and doffing techniques, and considerations for safe use. Durand noted that all materials are available on the CDC website, and recommendation development is an ongoing process.²

Farmworker H5N1 Seroprevalence Research

Given that people exposed to A(H5N1) virus-infected animals—particularly those not using PPE—are at greater risk of infection, CDC has conducted serological studies to identify potential undetected cases in exposed persons and better understand risk among farmworkers and veterinarians, said Durand. In one study, CDC collaborated with the Michigan Department of Health and Human Services and the Colorado Department of Public Health and Environment to conduct serosurveys in farmworkers (Mellis et al., 2024). In a cohort of 115 people working with cattle infected with A(H5N1) virus, eight participants (7 percent) had evidence of recent A(H5) virus infection, four of whom did not recall feeling sick or experiencing symptoms. The identification of infected workers who did not report illness is important evidence that informs new guidance to protect workers, Durand underscored. Based on these findings, the agency updated existing recommendations to reduce exposure to infected animals. An additional CDC serosurvey conducted in collaboration with the Ohio Department of Health and the American Association of Bovine Practitioners studied veterinarians and veterinary technicians and students (Leonard et al., 2025). In September 2024, researchers collected serum samples from 150 individuals who practiced across 46 U.S. states and Canada. Testing revealed that three participants (2 percent) had antibodies to A(H5) virus, indicating recent infection, but none reported having respiratory or flu-like symptoms since January 2024. At the time of the survey, two of these participants worked in states with known A(H5N1) virus-infected dairy herds, but the third did not work in a state with reported infected herds. All participants reported wearing gloves or protective clothing, though none reported using any respiratory or eye protection. Durand stated that this study highlights the importance of rapid detection of A(H5N1) virus in dairy herds through herd and bulk tank testing programs.

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² Multilingual CDC informational materials for farmworkers are available at https://www.cdc.gov/bird-flu/communication-resources/farm-workers-h5n1.html (accessed November 17, 2025).

Farmworker Outreach Efforts

Durand noted that CDC outreach to farmworkers on H5N1 is ongoing. By extending $5 million in funding to partner organizations, CDC is investing in protecting the health of farmworkers. These investments include supporting the National Center for Farmworker Health’s outreach efforts, which provide H5N1 and seasonal influenza education to animal production workers via a network of supported national nongovernmental organizations and community-based organizations in affected states. Partner organizations have delivered technical assistance, listening sessions, focus groups, and trainings on H5N1 prevention, mitigation, and access to information. Additionally, CDC conducted targeted social media and digital outreach efforts that provided information in English and Spanish about H5N1 risks, recommended precautions, symptoms, and steps to take should symptoms develop. The agency also developed a Toolbox Talk resource to support focused discussions between employers and workers on workplace hazards.³ This guide is designed to help employers instruct workers on proper PPE use, including how PPE works and how to safely don and doff it, said Durand.

Current Status of H5N1 Response

The CDC A(H5N1) response officially deactivated in July 2025, but Durand emphasized that agency efforts to mitigate A(H5N1) continue within the NCIRD Influenza Division. Using long-standing infrastructure built to respond to seasonal and novel influenza epidemics, CDC continues to collaborate with state and local health departments to monitor exposed individuals and conduct routine surveillance through existing influenza, wastewater, and national syndromic surveillance systems. Moreover, CDC will maintain One Health touchpoints with USDA and other interagency partners and continue outreach to higher-risk populations. Current data indicate the overall risk of A(H5N1) to the public remains low. However, people with work or recreational exposure to A(H5N1)-infected animals may face increased risk and should follow recommended precautions. CDC continues to work with local, state, and federal partners to conduct public health surveillance and monitor for changes in the epidemiology of human cases or viral characteristics that could signal an increased public health threat, said Durand.

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³ The CDC H5N1 Toolbox Talk is available in English and Spanish at https://www.cdc.gov/bird-flu/worker-safety/ppe-training-materials.html (accessed November 17, 2025).

WORKSHOP OBJECTIVES

The National Academies of Sciences, Engineering, and Medicine’s Board on Health Sciences Policy hosted a two-day public workshop—Personal Protective Equipment for Influenza A(H5N1) in High-Risk Farm Settings—to examine PPE needs and best practices in protecting farmworkers and mitigating H5N1 transmission between animals and humans. The workshop was held on September 29–30, 2025, and featured invited presentations and discussions to:

• Consider the latest scientific evidence on H5N1 transmission and remaining uncertainties and implications for PPE use in high-risk farm settings, including the role of PPE relative to other kinds of controls (e.g., engineering, administrative).
• Examine U.S. regulatory frameworks and explore needed reforms to improve PPE use for preventing zoonotic disease transmission, with a focus on current guidance, best practices, and gaps in high-risk farm settings.
• Highlight individual-level and systemic barriers to PPE access and use in high-risk farm settings and explore potential solutions to overcome these barriers, including the roles of novel technologies, communication, and education and training.
• Highlight key research needs to evaluate and improve the effectiveness of PPE when used in high-risk farm settings to protect workers and control the spread of zoonotic diseases.
• Consider opportunities to improve future responses to emerging and re-emerging infectious diseases that have the potential to spread between livestock and humans.

ORGANIZATION OF THE PROCEEDINGS

This Proceedings of a Workshop summarizes the presentations and discussions that took place during the public workshop held on September 29–30, 2025. Chapter 2 provides the landscape of H5N1 agricultural outbreaks, detailing the timeline, locations, and suspected transmission routes of viral spread to livestock and humans in the poultry and dairy industries. Chapter 3 outlines responses to H5N1 infections from the federal government, public health, and poultry and dairy sectors. Chapter 4 explores individual barriers to PPE use in H5N1 infection control from the perspectives of producers, researchers, safety educators, and agricultural extension agents. Chapter 5 examines systemic barriers to H5N1 infection control, including demographic, policy, regulatory, social, and workplace factors. Chapter 6 considers improving existing PPE access and feasibility of use via

partnerships, farmworker education and outreach, resource development, stockpile strategies, and alternative forms of PPE. Chapter 7 highlights innovative PPE technology, research, and potential designs and features while identifying regulatory and economic barriers to innovation. Chapter 8 discusses implementation considerations and strategies for effective farmworker communications and educational outreach. Chapter 9 features a roundtable discussion, bringing together experts from the broiler, layer, and dairy industries and from the research, public health, and One Health fields to address aspects of contending with an evolving zoonotic virus. Chapter 10 provides a summary of insights and themes from the workshop as well as reflections and next steps from the workshop sponsor. References follow Chapter 10, Appendix A contains the workshop agenda, and Appendix B includes brief biographies of planning committee members, speakers, and workshop staff.

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