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Notice to Readers Results of The Public Health Response to Pfiesteria Workshop -- Atlanta, Georgia, September 29-30, 1997

MMWR 46(40);951-952

Publication date: 10/10/1997

Table of Contents




On September 29-30, 1997, CDC sponsored a workshop to coordinate a multistate response to public health issues about Pfiesteria piscicida. Workshop attendees included representatives from the health departments of eight states (Delaware, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, and West Virginia) and the District of Columbia, the U.S. Food and Drug Administration, the National Institutes of Health's National Institute of Environmental Health Sciences, CDC's National Institute for Occupational Safety and Health, and the U.S. Environmental Protection Agency.

P. piscicida and morphologically related organisms (MROs) are dinoflagellates that have been implicated in recent estuarine * fish kills on the U.S. eastern seaboard and have been reported to be associated with human illness. These dinoflagellates appear similar under light microscopy and require scanning electron microscopy for definitive identification. The attendees of the workshop agreed on a combined set of environmental conditions and clinical signs and symptoms that together may represent adverse consequences of exposure to these organisms. The environmental conditions are exposure to estuarine water characterized by any of the following: 1) fish with lesions consistent with P. piscicida or MRO toxicity (20% of a sample of at least 50 fish of one species having lesions); 2) a fish kill involving fish with lesions consistent with P. piscicida or MRO toxicity; or 3) a fish kill involving fish without lesions, if P. piscicida or MROs are present and there is no alternative reason for the fish kill. The clinical features in humans include any of the following signs and symptoms: 1) memory loss, 2) confusion, 3) acute skin burning (on direct contact with water), or 4) three or more of an additional set of conditions (headaches, skin rash, eye irritation, upper respiratory irritation, muscle cramps, and gastrointestinal complaints {i.e., nausea, vomiting, diarrhea, and/or abdominal cramps}).

Workshop attendees suggested using the above framework to identify potentially affected persons and recommended initiating the following public health activities: 1) uniform multistate surveillance for potential P. piscicida- and MRO-related illness; 2) multistate, CDC-coordinated, epidemiologic studies to determine possible human health effects associated with P. piscicida and MRO exposure; and 3) identification of a biomarker of exposure to the toxins produced by these organisms. The public health implication of toxicity of these dinoflagellates is an example of an emerging environmental and potential occupational health issue that can best be addressed through collaboration among federal, state, and local health agencies.

Reported by participants in The Public Health Response to Pfiesteria Workshop: AL Hathcock, PhD, Div of Public Health, Delaware Health and Social Svcs; ME Levy, MD, District of Columbia Commission of Public Health; S Wiersma, MD, Florida Dept of Health; CL Drenzek, DVM, Div of Public Health, Georgia Dept of Human Resources; MP Wasserman, MD, Maryland State Dept of Health and Mental Hygiene; R Levine, MD, S Music, DTPH, North Carolina Dept of Health and Human Svcs; R Ball, MD, South Carolina Dept of Health and Environmental Control; SR Jenkins, VMD, Virginia State Health Dept; C Berryman, DVM, Bur of Public Health, West Virginia Dept of Health and Human Resources; Office of Public Health and Science, US Dept of Health and Human Svcs; Office of Seafood, Center for Food Safety and Applied Nutrition, US Food and Drug Administration; Geographic Planning and Technology Support Br, Water Management Div, Region IV, US Environmental Protection Agency; Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health; Hazard Evaluations and Technical Assistance Br, Div of Surveillance, Hazard Evaluations, and Field Studies, National Institute for Occupational Safety and Health, Toxicology Br, Div of Environmental Health Laboratory Sciences, and Health Studies Br, Div of Environmental Hazards and Health Effects, National Center for Environmental Health, CDC.

* A coastal area at the mouth of a river where fresh river water mixes with salty sea water.


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