Potential Zoonoses Associated with Fish and Amphibians


The intent of this Resource Page is to describe the most common zoonotic agents seen in aquatic animals, such as fish and amphibians, and the safe work practices suggested to mitigate the exposure to these pathogens.

This page provides information about potential zoonotic exposure while working with aquatic animals or their products (e.g. tissue samples). The infectious agents listed here are not all inclusive, but provide the most common zoonotic agents seen in aquatic animals. The safe work practices are provided as suggestions for staff and researchers who work with animals, in animal facilities, or with animal

Zoonotic Pathogens

  1. Mycobacterium
    • Organisms: Mycobacterium spp. (most often M. marinum and fortuitum).
    • Clinical Signs:
      • Animals – Multifocal skin sores in amphibians and nodules in fish.
      • Humans – Skin sores at site of infection; disseminated disease in immunosuppressed individuals.
    • Transmission: Contamination of tiny scratches on the hand or skin.
  2. Fish Handler’s Disease or Erysipelas
    • Organisms: Erysipelothrix rhusiopathiae
    • Clinical Signs:
      • Animals – Asymptomatic or diarrhea.
      • Humans – Localized skin sore with pain and swelling, may lead to more widespread skin or systemic infection.
    • Transmission: Contamination of tiny scratches on the hand or skin.
  3. Salmonellosis
    • Organism: Salmonella spp.
      • Clinical Signs:
        • Animals – Asymptomatic
        • Humans – Diarrhea, nausea, vomiting, abdominal pain.
      • Transmission: Accidental ingestion of contaminated water / environment.

Safe Work Practices

  1. Good Personal Hygiene
    • Wash hands after working with animals or animal products and when leaving animal facilities.
    • Do not eat, drink, or use tobacco products in animal facilities.
  2. Personal Protective Equipment (PPE)
    • Use proper PPE for work setting as appropriate (e.g. coverall, facemask, boot covers). Maintain dedicated protective clothing and footwear while working with animals or in animal facilities. Do not wear protective clothing outside of animal facility.
    • Wear disposable gloves during procedures that increase the likelihood of exposure to zoonotic agents (e.g. handling of aquatic animals or cleaning holding tanks / aquariums). Exercise increased caution when handling sick animals (i.e. animals showing clinical signs such as skin lesions and lethargy) or when you have an exposed break in skin (e.g. cut or scratch).
    • Use face masks/googles when appropriate (i.e. activities where splashing of water may occur).
  3. Animal Care
    • Isolate sick or infected animals when possible.
    • Handle and care for sick or infected animals last.
  4. Cleaning and Disinfection
    • Maintain clean, dry, and uncluttered animal areas and workspace.
    • Disinfect laboratory work surfaces after each use. Use only disinfectants approved by facility management and that are suitable for the potential agents identified on this page.
    • Dispose of deceased animals, animal products, items contaminated by animal products, contaminated materials, and laboratory waste in a facility approved manner.
  5. Proper Sharps Handling
    • Work only with one uncapped needle at a time and immediately dispose of after use in sharps receptacle.
    • Avoid recapping needles whenever possible.
  6. Medical Attention
    • Contact the Cornell Health Occupational Medicine service at 607-255-6960 for medical evaluation if you suspect any exposure, or if you develop any symptoms associated with infection with zoonotic agents (e.g., fever, malaise, diarrhea, abdominal pain). Alternatively, see your own personal health care provider if any injury or potential exposure to a zoonotic agent occurs.
    • Notify the principal investigator or supervisor and complete the Environmental Health and Safety and Risk Management Injury / Illness / Exposure Report.
  7. Allergies
    • Handling of bedding, hair, fur, and animal products may aggravate allergies.
    • Proper use of PPE reduces, but does not eliminate, the risk of developing allergies. Refer to the Allergy Prevention Fact Sheet for further information.


  1. CDC: Take Care with Pet Reptiles and Amphibians
  2. Cornell Health