A Field Guide for Early Detection, Recognition, and Reporting
Aquatic animal diseases can impact aquaculture, fisheries, aquatic ecosystems, and trade. Many pathogens spread rapidly through animal movements, interconnected water systems, and human activities. Once established, they may be difficult or impossible to eliminate.
Early recognition and prompt reporting are critical for limiting disease spread, protecting aquatic animal health, and reducing impacts on aquatic industries and natural resources. Whether you are a producer, veterinarian, researcher, resource manager, or pet owner, you play an important role in safeguarding aquatic animal health in the United States.
About this Field Guide
This field guide helps users recognize and report aquatic animal pathogens of regulatory concern in the United States. It covers reportable diseases affecting fish, crustaceans, mollusks, and amphibians listed in the USDA National List of Reportable Animal Diseases (NLRAD), including those internationally notifiable to the World Organisation for Animal Health (WOAH).
For information on the current status of aquatic animal pathogens in the U.S., visit the NLRAD webpage. Pathogens that are declared or presumed absent from the U.S. are listed in the USDA Aquatic Animal Health Status Review.
Start Exploring
Each disease profile includes pathogen information, clinical signs, prevention considerations, sampling guidance, reporting requirements, and full-color disease images.
Important: This guide is for awareness and educational purposes only. Field observations cannot confirm disease, and laboratory testing is required for diagnosis. This information does not replace official case definitions or regulatory guidance. The NLRAD webpage also provides case definitions of each listed pathogen.
Who Should Use This Guide
This field guide is designed for anyone working with or observing aquatic animals. Whether you manage aquatic animal populations, provide animal health services, conduct field surveillance, or care for aquatic animals, this guide provides practical information on reportable aquatic animal pathogens for the United States, to support disease recognition and reporting.
Intended users include:
- Aquaculture producers and farm managers
- Hatchery operators and technicians
- Fisheries biologists and aquatic resource managers
- Aquatic animal veterinarians and health professionals
- Extension specialists and Sea Grant agents
- Diagnostic laboratory personnel
- Researchers and field personnel
- State, tribal, and federal animal health officials
- Zoo and aquarium staff
- Aquarium, pond and pet owners
Pathogen Reporting
All of the diseases and pathogens on this site are reportable in the United States.
Report concerns if you observe these signs in farmed or wild fish, crustaceans, mollusks, or amphibians:
- Unexplained illness or death
- Rapid spread of illness within a population or facility
- Unusual clinical signs for a species or operation
- Disease events involving multiple species or locations
- Illness following recent animal introductions or movements
If these signs are seen, contact your state aquatic animal health agency (e.g., State Veterinarian) and the USDA.
For more information about where and how to report, and diagnostic testing and laboratory support, visit Pathogen Reporting and Notification.
Acknowledgements
These resources were developed by the Center for Food Security and Public Health (CFSPH) with funding from USDA APHIS through the National Animal Disease Preparedness and Response Program (NADPRP).