Fish viruses are pathogens that specifically infect fish species, causing various diseases that can impact fish health and aquaculture. These viruses can lead to symptoms such as lesions, swelling, and abnormal behavior, affecting both wild and farmed fish populations. Common types of fish viruses include Infectious Hematopoietic Necrosis Virus (IHNV) and Viral Hemorrhagic Septicemia Virus (VHSV). Transmission of fish viruses often occurs through contaminated water, infected fish, or equipment. Effective management practices, such as maintaining water quality and monitoring fish health, are essential to prevent outbreaks. Understanding these viruses is crucial for protecting both natural ecosystems and the aquaculture industry.