Aphanomyces sp.

Also known as: Water mold, Epizootic Ulcerative Syndrome (EUS)

Aphanomyces is a genus of water molds that cause severe infections in fish, often leading to ulcerative lesions, necrosis, and systemic disease. Aphanomyces invadans is the primary pathogen responsible for Epizootic Ulcerative Syndrome (EUS), a devastating disease affecting freshwater and estuarine fish worldwide. The infection often starts as small red or white patches that develop into deep ulcers, exposing muscle and internal organs.

Distribution: Global, particularly in tropical and subtropical freshwater environments
Hosts: A wide range of freshwater and estuarine fish species
Detection Methods: Microscopic examination of infected tissue, histopathology, PCR for species identification
Target tissue: Skin, muscle, internal organs