Understanding the Introduction of Pathogens into Humans

Preventing Patient Zero

Convened January 15–16, 2025

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Maartje Wouters, Elizabeth Ashby Guo, and Julie Liao, Rapporteurs

Forum on Microbial Threats

Board on Global Health

Health and Medicine Division

Proceedings of a Workshop

NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001

This activity was supported by contracts between the National Academy of Sciences and the Centers for Disease Control and Prevention (75D30 121D11240/75D30122F00011), the Department of Homeland Security (70RWMD24FRP000001), and Merck Sharp & Dohme LLC (PP-24-184630), as well as sponsorship from the American Society of Tropical Medicine and Hygiene, the Burroughs Wellcome Fund, the Infectious Diseases Society of America, and the Society of Infectious Diseases Pharmacists. The views expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

International Standard Book Number-13: 978-0-309-60176-4
Digital Object Identifier: https://doi.org/10.17226/29313

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2026. Understanding the introduction of pathogens into humans: Preventing patient zero: Proceedings of a workshop. Washington, DC: National Academies Press. https://doi.org/10.17226/29313.

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PLANNING COMMITTEE ON UNDERSTANDING THE INTRODUCTION OF PATHOGENS INTO HUMANS

DANIEL BAUSCH (Cochair), National University of Singapore

SUMIKO MEKARU (Cochair), Epivoyant, LLC

KEVIN ANDERSON, Retired

CRISTINA CASSETTI, National Institute of Allergy and Infectious Diseases, National Institutes of Health

RICARDO CASTILLO, University of Pennsylvania

ANDREW CLEMENTS, U.S. Agency for International Development

PAYEL DAS, IBM

GIGI GRONVALL, Johns Hopkins Bloomberg School of Public Health

KEITH KLUGMAN, Bill and Melinda Gates Foundation

CARLA SAENZ, Pan American Health Organization

APARUPA SENGUPTA, Nuclear Threats Initiative

MATIANGAI SIRLEAF, University of Maryland, Baltimore

JONATHAN SLEEMAN, U.S. Geological Survey

Forum on Microbial Threats Staff

JULIE LIAO, Director, Forum on Microbial Threats

ELIZABETH ASHBY GUO, Program Officer (through May 2025)

TAYLOR WINDMILLER, Senior Program Assistant (through March 2025)

JULIE PAVLIN, Science Advisor, Health and Medicine Division (through March 2025)

CAROLYN SHORE, Global Health Lead, Health and Medicine Division (as of February 2025)

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FORUM ON MICROBIAL THREATS¹

KENT E. KESTER (Chair), Coalition for Epidemic Preparedness Innovations

CRISTINA CASSETTI (Vice Chair), National Institute of Allergy and Infectious Diseases, National Institutes of Health

KEITH P. KLUGMAN (Vice Chair), Bill and Melinda Gates Foundation

EMILY ABRAHAM, Johnson & Johnson

KEVIN ANDERSON, Retired

DAN H. BAROUCH, Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center

DANIEL BAUSCH, National University of Singapore

NAHID BHADELIA, Boston University Center for Emerging Infectious Disease

CHRISTOPHER BRADEN, U.S. Centers for Disease Control and Prevention

RICK A. BRIGHT, Bright Global Health

AMBIKA BUMB, Bipartisan Commission on Biodefense

ANDREW CLEMENTS, U.S. Agency for International Development

TRACEY DUTCHER, U.S. Department of Homeland Security

GREG FRANK, Merck & Co., Inc.

WONDWOSSEN GEBREYES, The Ohio State University

BRUCE G. GELLIN, Georgetown University School of Medicine

GIGI KWIK GRONVALL, Johns Hopkins University

ELIZABETH D. HERMSEN, Pfizer

ALBERT I. KO, Yale School of Public Health

LINDA S. LLOYD, San Diego State University School of Public Health

SYRA MADAD, NYC Health + Hospitals

VICTORIA MCGOVERN, Burroughs Wellcome Fund

SUMIKO MEKARU, Epivoyant, LLC

TIMOTHY D. MURRAY, Washington State University

MELISSA NOLAN, University of South Carolina

RAFAEL OBREGÓN, UNICEF

BENJAMIN PINSKY, Stanford University School of Medicine

AMEET J. PINTO, Georgia Institute of Technology

P. DAVID ROGERS, St. Jude Children’s Research Hospital

UMAIR SHAH, Washington State Department of Health

JONATHAN SLEEMAN, U.S. Geological Survey

MATTHEW ZAHN, Orange County Health Care Agency (California)

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¹The National Academies of Sciences, Engineering, and Medicine’s forums and roundtables do not issue, review, or approve individual documents. The responsibility for the published Proceedings of a Workshop rests with the workshop rapporteurs and the institution.

Forum on Microbial Threats Staff

JULIE LIAO, Director, Forum on Microbial Threats

ELIZABETH ASHBY GUO, Program Officer (through May 2025)

TAYLOR WINDMILLER, Senior Program Assistant (through March 2025)

JULIE PAVLIN, Science Advisor, Health and Medicine Division (through March 2025)

CAROLYN SHORE, Global Health Lead, Health and Medicine Division (as of February 2025)

Reviewers

This Proceedings of a workshop was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published proceedings as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the charge. The review comments and draft manuscript remain confidential to protect the integrity of the process.

We thank the following individual for their review of this proceedings:

ERIN SORRELL, Johns Hopkins University

Although the reviewer listed above provided many constructive comments and suggestions, they were not asked to endorse the content of the proceedings nor did they see the final draft before its release. The review of this proceedings was overseen by HUGH TILSON, North Carolina Area Health Education Centers. He was responsible for making certain that an independent examination of this proceedings was carried out in accordance with standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the rapporteurs and the National Academies.

We also thank staff member STEPHEN MAHER for reading and providing helpful comments on this manuscript.

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Acknowledgements

We extend our sincere gratitude to the planning committee cochairs, Daniel Bausch and Sumiko Mekaru, for their invaluable contributions to the development and orchestration of this workshop. We also thank the members of the planning committee for their collaborative efforts in ensuring a program enriched with informative presentations and engaging discussions.

Our appreciation goes to the speakers, who generously shared their time and expertise with workshop participants. We are also grateful to the membership of the National Academies Forum on Microbial Threats for their support of the workshop and for providing thoughtful input throughout the process.

Finally, we thank staff members, Carolyn Shore and Taryn Young, for reading and providing helpful comments on this manuscript, Mark Goodin for his meticulous copy editing, and Lori Brenig for her valuable assistance with figure preparation.

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Contents

1 Introduction

WORKSHOP OBJECTIVE

2 Pathogen Introduction into Humans

PATHOGEN EXPOSURE FROM WILDLIFE

PATHOGEN EXPOSURES FROM FARMING AND AGRICULTURE

PATHOGEN EXPOSURE FROM LABORATORY SETTINGS

INTENTIONAL RELEASE AND BIOSECURITY

DISCUSSION

3 Pathogen Amplification and Dissemination

PATHOGEN DYNAMICS AND SPILLOVER

AMPLIFICATION IN SECONDARY HOSTS

AMPLIFICATION IN HEALTH CARE SETTINGS

OVERCOMING BLIND SPOTS IN PATHOGEN DETECTION

DISCUSSION

4 Forecasting, Surveillance, and Early Warning

PREDICTION AND FORECASTING

AI-DRIVEN HEALTH SECURITY

DATA INTEGRATION AT EARLY STAGES OF OUTBREAKS

AI GOVERNANCE AND GLOBAL INCLUSION

DISCUSSION

5 Interventions for Prevention and Mitigation

SOCIETAL FRAMING FOR BEHAVIORAL INTERVENTIONS

DIAGNOSTICS FOR EARLY WARNING

NATURE-BASED SOLUTIONS

MITIGATION OF RISKS IN AGRICULTURAL SETTINGS

LABORATORY BIOSAFETY AND BIOSECURITY

DISCUSSION

6 Legal, Ethical, and Policy Considerations

POLICY CONSIDERATIONS FOR ONE HEALTH

ENABLING ADVANCED WARNING TO PREVENT SPILLOVER

DISCUSSION

7 Opportunities to Prevent Patient Zero

PREVENTING PATIENT ZERO

ENGAGING DIFFERENT STAKEHOLDERS

INTEGRATING PUBLIC AND ECOSYSTEM HEALTH

BROADER APPROACHES

TRADE-OFFS

INCENTIVES

IN CLOSING

References

Appendix: Workshop Agenda

Boxes and Figures

BOXES

1-1 Workshop Statement of Task

2-1 One Health

FIGURES

4-1 Overview of a global warning system for infectious diseases

5-1 Framework for behavioral interventions

7-1 The progression of infectious disease prevention

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Abbreviations