Pfiesteria

A long-simmering scientific controversy over Pfiesteria piscicida, the microscopic cell suspected of killing fish and making people sick, reached the boiling point yesterday when five North Carolina scientists challenged the work of the nation's main Pfiesteria expert. The scientists, led by biologist Wayne Litaker of the University of North Carolina, published the results of their research, saying they believe Pfiesteria is not the complicated creature described by JoAnn Burkholder of North Carolina State University, the organism's co-discoverer.

The victims thrashed wildly until at last they expired, their silvery remains, pocked with open sores, littering the lower Pocomoke River in August 1997. Investigators quickly pointed to Pfiesteria piscicida, a single-celled algae blamed for fish kills in estuaries behind North Carolina's Outer Banks in the 1980s. Almost as quickly, state and federal agencies awarded millions in research grants in an effort to unlock the mysteries of the microbe. Now some researchers are saying that they misidentified the culprit.

GLOUCESTER POINT, Va. - Virginia Institute of Marine Science scientists Kimberly Reece and Nancy Stokes have developed molecular diagnostic tools to detect Pfiesteria piscicida and related organisms in water samples. The tools were developed using funds for Pfiesteria research provided to VIMS by the Virginia General Assembly and a grant from Environmental Protection Agency. The researchers used the tools to look for Pfiesteria in water samples collected during September and October by the Department of Environmental Quality.

The discovery of a parasite responsible for a fish kill in Virginia last month has thrown another variable into attempts to understand the toxic microbe Pfiesteria piscicida.Although signs pointed to Pfiesteria, Virginia scientists found that Kudoa, a parasite more often associated with fish ponds than Chesapeake Bay tributaries, killed hundreds of menhaden in the James River between Newport News and Hampton Oct. 20-22."The salinity in that part of the river was right [for Pfiesteria]; it was warm and shallow, and it was fall, the same time of the year we had the other events," said Greg C. Garman, a Virginia Commonwealth University fish biologist.

The state's Pfiesteria rapid response team is investigating a stretch of the Chicamacomico River where workers found a small number of menhaden with fresh Pfiesteria piscicida-like lesions yesterday.The site, near a ruined drawbridge on a slender, remote stretch of the river about four miles southwest of Vienna on the Lower Eastern Shore, was the scene of Maryland's fourth and last Pfiesteria-related fish kill of 1997. On Sept. 14, Gov. Parris N. Glendening ordered a six-mile stretch of the Chicamacomico closed after about 4,000 fish died of toxic Pfiesteria near the drawbridge.

Pfiesteria has been ruled out as the cause of rashes on two environmental workers a week ago, but a third case remained under investigation yesterday and state officials urged people around the Manokin River in Somerset County to remain wary of the toxic microbe.Maryland Department of Natural Resources officials were optimistic after periodic weekend checks of the area around Back Creek, a tributary of the Manokin, turned up no fish kills or other signs of Pfiesteria. Two years ago, the toxin killed more than 30,000 fish and sickened 13 people in Maryland.

In the first study of its kind, neurological and environmental researchers will use a $2 million federal grant to study how the fish-killing microorganism Pfiesteria affects humans, the University of Maryland announced yesterday.The grant, awarded last year by the National Institute of Environmental and Health Science, will be used by a newly formed group that will study the effects of Pfiesteria on the human brain and nervous system.Pfiesteria caused huge fish kills in the Pocomoke River and adjacent Eastern Shore waterways in August 1997.

University of Maryland scientists have been awarded more than $2.4 million in federal and state funds to study the causes of Pfiesteria outbreaks in Atlantic coastal waters, officials announced yesterday.The federal grants from the National Oceanic and Atmospheric Administration are the first of a five-year research effort aimed at finding out how Pfiesteria and related dinoflagellates interact with their aquatic environment.Two UM institutions have received more than $1.6 million in federal Pfiesteria research grants so far, and Gov. Parris N. Glendening announced the state will give $800,000 toward the study.

Maryland medical officials have documented five cases of people who might have been sickened by Pfiesteria during the past three years, though no confirmed fish kills have been attributed to the toxic microorganism since 1997. Dr. Glenn Morris, director of the University of Maryland School of Medicine's Pfiesteria research program, said yesterday that the five people all have symptoms consistent with an illness known as estuarine associated syndrome, which was first identified after a major outbreak of Pfiesteria on Maryland's Pocomoke River in 1997.