Pfiesteria piscicida and Ulcerative Mycosis of Atlantic Menhaden—Current Status of Understanding

Abstract Ulcerative lesions in estuarine finfish are associated with a variety of parasitic, bacterial, and fungal infectious agents as well as water quality and other abiotic stress factors. Atlantic menhaden Brevoortia tyrannus are a severely affected species typically exhibiting solitary, perianal, focal, deep, granulomatous lesions containing oomycete hyphae. Intense recent emphasis in the scientific literature and in the popular press has been placed on Pfiesteria-like dinoflagellates and their toxins as the causative agents for ulcerative finfish lesions in east coast estuaries of the United States. Dramatic descriptive terms for Pfiesteria, including “phantom,” “ambush-predator” and “the cell from hell,” capable of affecting humans, have appeared in scientific journals and the news media. However, there is no scientific evidence to date that supports a single, causal relationship between the presence of toxic Pfiesteria-like dinoflagellates and fish kills or the associated ulcerative lesions. This ...