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zoonotic

Zoonotic Diseases Hub

As human populations grow and expand into new areas, our contact with wild and domestic animals is changing, creating the need for a better understanding that the health of people is inextricably linked with the health of animals and our shared environment.

Human & Veterinary Medical Expertise in One Resource

View zoonotic diseases from both animal and human-health perspectives. Find plain-language information in the Consumer Edition or explore clinical guidance in the Professional Edition.

Central Information Hub

Explore zoonotic disease information - from common symptoms and prevention strategies to treatment options and what to know about recent outbreaks.

Integrated Health Information

Navigate to information about specific diseases and toggle easily to learn how both humans and animals are affected.

video

Zoonotic Diseases: When Infections Cross Species

Approximately 60% of human pathogens are zoonotic, representing the majority of emerging infectious diseases. This video reviews the veterinary transmission pathways, clinical management of animal reservoirs, and essential clinic biosecurity protocols to mitigate occupational and public health risks.

Trending Topics

Explore Zoonotic Diseases by Type

Meet The Experts

Our content is written by a multidisciplinary panel of experts in human and veterinary medicine. Learn about our editorial process. Meet some of our featured experts:

  • Domenico Galante

    DVM

    Anthrax Reference Institute of Italy (Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata)

    Anthrax infection; Acute pain

  • Phillip D. Carter

    BVSc, MVS

    Local Land Services, New South Wales, Australia

    Diagnosis, management, and vaccine production for babesiosis and anaplasmosis

  • John WA Larsen

    BVSc, PhD

    Faculty of Veterinary and Agricultural Sciences, University of Melbourne

    Production systems, Sheep and goat diseases, Beef cattle

  • Phillip D. Carter

    BVSc, MVS

    Local Land Services, New South Wales, Australia

    Diagnosis, management, and vaccine production for babesiosis and anaplasmosis

  • John WA Larsen

    BVSc, PhD

    Faculty of Veterinary and Agricultural Sciences, University of Melbourne

    Production systems, Sheep and goat diseases, Beef cattle

  • Thomas Edling

    DVM

    American Humane

    Care of nontraditional companion animals; Animal ethics; Zoonotic disease transmission; Veterinary public health

  • John WA Larsen

    BVSc, PhD

    Faculty of Veterinary and Agricultural Sciences, University of Melbourne

    Production systems, Sheep and goat diseases, Beef cattle

  • Thomas Edling

    DVM

    American Humane

    Care of nontraditional companion animals; Animal ethics; Zoonotic disease transmission; Veterinary public health

  • Arnaud J. Van Wettere

    DVM, PhD, DACVP

    College of Veterinary Medicine, Utah State University

    Veterinary pathology; Avian and wildlife pathology; Hepatic pathology

  • Thomas Edling

    DVM

    American Humane

    Care of nontraditional companion animals; Animal ethics; Zoonotic disease transmission; Veterinary public health

  • Arnaud J. Van Wettere

    DVM, PhD, DACVP

    College of Veterinary Medicine, Utah State University

    Veterinary pathology; Avian and wildlife pathology; Hepatic pathology

  • Juan José Badiola

    DVM, DECVP

    Department of Animal Pathology, Faculty of Veterinary Medicine, University of Zaragoza, Spain

    Transmissible spongiform encephalopathies; Veterinary pathology

  • Arnaud J. Van Wettere

    DVM, PhD, DACVP

    College of Veterinary Medicine, Utah State University

    Veterinary pathology; Avian and wildlife pathology; Hepatic pathology

  • Juan José Badiola

    DVM, DECVP

    Department of Animal Pathology, Faculty of Veterinary Medicine, University of Zaragoza, Spain

    Transmissible spongiform encephalopathies; Veterinary pathology

  • Sarah Hamer

    DVM, PhD, DACVPM-Epidemiology

    Department of Veterinary Integrative Biosciences, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University

    Wildlife and zoonotic disease ecology and epidemiology; Vector-borne disease; Public health

  • Juan José Badiola

    DVM, DECVP

    Department of Animal Pathology, Faculty of Veterinary Medicine, University of Zaragoza, Spain

    Transmissible spongiform encephalopathies; Veterinary pathology

  • Sarah Hamer

    DVM, PhD, DACVPM-Epidemiology

    Department of Veterinary Integrative Biosciences, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University

    Wildlife and zoonotic disease ecology and epidemiology; Vector-borne disease; Public health

  • Alex Pauvolid-Corrêa

    DVM, PhD

    Preventive Veterinary Medicine and Public Health, Department of Veterinary, Federal University of Viçosa, Brazil

    Emerging zoonotic viral diseases; Veterinary virology; Laboratory diagnostic in virology; Active surveillance for enzootic arboviruses

  • Sarah Hamer

    DVM, PhD, DACVPM-Epidemiology

    Department of Veterinary Integrative Biosciences, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University

    Wildlife and zoonotic disease ecology and epidemiology; Vector-borne disease; Public health

  • Alex Pauvolid-Corrêa

    DVM, PhD

    Preventive Veterinary Medicine and Public Health, Department of Veterinary, Federal University of Viçosa, Brazil

    Emerging zoonotic viral diseases; Veterinary virology; Laboratory diagnostic in virology; Active surveillance for enzootic arboviruses

  • Andrew S. Peregrine

    BVMS, PhD, DVM, DEVPC, DACVM-Parasitology

    Department of Pathobiology, Ontario Veterinary College, University of Guelph

    Clinical parasitology, Clinical pharmacology, Emerging zoonotic infections of companion animals, Gastrointestinal parasites of sheep

  • Alex Pauvolid-Corrêa

    DVM, PhD

    Preventive Veterinary Medicine and Public Health, Department of Veterinary, Federal University of Viçosa, Brazil

    Emerging zoonotic viral diseases; Veterinary virology; Laboratory diagnostic in virology; Active surveillance for enzootic arboviruses

  • Andrew S. Peregrine

    BVMS, PhD, DVM, DEVPC, DACVM-Parasitology

    Department of Pathobiology, Ontario Veterinary College, University of Guelph

    Clinical parasitology, Clinical pharmacology, Emerging zoonotic infections of companion animals, Gastrointestinal parasites of sheep

  • Alejandro Ramirez

    DVM, PhD, DACVPM

    College of Veterinary Medicine, University of Arizona

    Swine Medicine; Preventive Medicine; Public Health; Biosecurity

  • Alejandro Ramirez

    DVM, PhD, DACVPM

    College of Veterinary Medicine, University of Arizona

    Swine Medicine; Preventive Medicine; Public Health; Biosecurity

  • David E. Swayne

    DVM, PhD, DACVP, DACPV

    Birdflu Veterinarian, LLC

    Pathology of Avian Diseases; Virology of Avian Diseases; Prevention and control of Avian Influenza; Prevention and control of Newcastle disease

  • Richard W. Gerhold, Jr.

    DVM, PhD, MS

    Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee

    Parasitology, Wildlife disease ecology

  • Katharine F. Lunn

    BVMS, PhD, DACVIM-SAIM

    Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University

    Small animal internal medicine

  • Domenico Galante

    DVM

    Anthrax Reference Institute of Italy (Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata)

    Anthrax infection; Acute pain

  • Phillip D. Carter

    BVSc, MVS

    Local Land Services, New South Wales, Australia

    Diagnosis, management, and vaccine production for babesiosis and anaplasmosis

  • Domenico Galante

    DVM

    Anthrax Reference Institute of Italy (Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata)

    Anthrax infection; Acute pain

  • Phillip D. Carter

    BVSc, MVS

    Local Land Services, New South Wales, Australia

    Diagnosis, management, and vaccine production for babesiosis and anaplasmosis

  • John WA Larsen

    BVSc, PhD

    Faculty of Veterinary and Agricultural Sciences, University of Melbourne

    Production systems, Sheep and goat diseases, Beef cattle

  • Thomas Edling

    DVM

    American Humane

    Care of nontraditional companion animals; Animal ethics; Zoonotic disease transmission; Veterinary public health

  • Arnaud J. Van Wettere

    DVM, PhD, DACVP

    College of Veterinary Medicine, Utah State University

    Veterinary pathology; Avian and wildlife pathology; Hepatic pathology

  • Juan José Badiola

    DVM, DECVP

    Department of Animal Pathology, Faculty of Veterinary Medicine, University of Zaragoza, Spain

    Transmissible spongiform encephalopathies; Veterinary pathology

  • Sarah Hamer

    DVM, PhD, DACVPM-Epidemiology

    Department of Veterinary Integrative Biosciences, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University

    Wildlife and zoonotic disease ecology and epidemiology; Vector-borne disease; Public health

  • Alex Pauvolid-Corrêa

    DVM, PhD

    Preventive Veterinary Medicine and Public Health, Department of Veterinary, Federal University of Viçosa, Brazil

    Emerging zoonotic viral diseases; Veterinary virology; Laboratory diagnostic in virology; Active surveillance for enzootic arboviruses

  • Andrew S. Peregrine

    BVMS, PhD, DVM, DEVPC, DACVM-Parasitology

    Department of Pathobiology, Ontario Veterinary College, University of Guelph

    Clinical parasitology, Clinical pharmacology, Emerging zoonotic infections of companion animals, Gastrointestinal parasites of sheep

  • Alejandro Ramirez

    DVM, PhD, DACVPM

    College of Veterinary Medicine, University of Arizona

    Swine Medicine; Preventive Medicine; Public Health; Biosecurity

  • David E. Swayne

    DVM, PhD, DACVP, DACPV

    Birdflu Veterinarian, LLC

    Pathology of Avian Diseases; Virology of Avian Diseases; Prevention and control of Avian Influenza; Prevention and control of Newcastle disease

  • Richard W. Gerhold, Jr.

    DVM, PhD, MS

    Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee

    Parasitology, Wildlife disease ecology

  • Scott A. Dee

    DVM, MS, PhD, DACVM

    Pipestone Veterinary Services

    Veterinary microbiology

  • Sarah Depenbrock

    DVM, MS, DACVIM(LAIM)

    University of California Davis, School of Veterinary Medicine

    Internal medicine and surgery of livestock

  • Katharine F. Lunn

    BVMS, PhD, DACVIM-SAIM

    Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University

    Small animal internal medicine

Frequently Asked Questions

Explore answers to frequently asked questions about zoonotic diseases, including how infections spread between animals and people, who is at risk, prevention strategies, diagnosis, and the role of One Health in protecting human and animal health.

Approximately 60-75% of all emerging human infectious diseases are zoonotic in origin, which includes some of the largest global epidemics such as HIV, SARS-CoV, and Avian Influenza. Veterinarians serve as the first line of defense against these diseases and must protect themselves from occupational exposure while fulfilling their critical roles in caring for animals, safeguarding public health, and preserving the environment.

Veterinarians act as the first line of defense against zoonotic diseases by facilitating early detection, surveillance, and prevention. They use the One Health approach to consider animals, humans, and the environment in their treatment, prevention, and control strategies.

The term "zoonoses" comes from the Greek words "zoon," meaning animal, and "nosos," meaning illness. A zoonosis is any disease that can naturally be transmitted from vertebrate animals to humans. This term also includes diseases that can be transmitted from humans to animals, known as reverse zoonosis.

Pathogens circulate among animals in their natural environments, regardless of whether they cause illness in those animals. When humans and animals interact at the human-animal-environment interface, transmission from animals to humans can occur, a process known as spillover. The transmissibility of these pathogens depends on several variables, including pathogen, host, human, vector (if applicable), environmental, and other factors.

There are five main mechanisms of transmission from animals to humans:

  • foodborne: from food contaminated with feces from an infected animal
  • waterborne: from water contaminated with feces from an infected animal
  • vector-borne: such as being bitten by a tick, mosquito, or flea carrying the pathogen
  • direct contact: coming into contact with body fluids of an infected animal, including bites and scratches
  • indirect contact: through contact with inanimate objects or environmental contamination, such as pet habitats, barns, aquariums, soil, food, and water dishes.