By Pamela Wood
It was known as the "cell from hell." Pfiesteria piscicida is a single-celled species of algae that created huge problems in the Chesapeake Bay in the summer of 1997.
Pfiesteria bloomed and emitted toxins that killed fish and sickened watermen. As researchers tried to figure out what was going on, many people stopped swimming and avoided local seafood.
Reporters descended on the Eastern Shore and packed news conferences, trying to beat each other to the next scoop. Headlines were splashed across front pages and stories led the evening news.
The hype and panic even got its own catchy name: "pfiesteria hysteria."
But after several months of seemingly being everywhere, pfiesteria suddenly disappeared from the news pages and from people's memories. It's hardly mentioned publicly anymore.
"It was like a wildfire, it burned out of control. Then it burned out, literally," said Bill Sieling, who was in charge of seafood marketing for the state at the time.
Whatever happened to pfiesteria hysteria?
Still in the bay
According to Bruce Michael, a Maryland Department of Natural Resources official, nothing much happened to pfiesteria.
It's still here, living in the waters of the
Chesapeake Bay and our rivers - one of many potentially harmful species of algae. But since the late 1990s, conditions haven't been right to lead to explosive blooms of pfiesteria that release a toxin harmful to fish and people.
Scientists still are studying the details of how pfiesteria works and why it sometimes moves into life stages that produce the toxin.
"It's an organism that has different life stages, and the only one we are concerned about is when it turns into the life stage where it produces a toxin," said Mr. Michael, who works on water monitoring for DNR. "Pfiesteria has historically been identified in Chesapeake Bay and it's still there, but it's not in the toxic stage."
The problem with pfiesteria is that it produces a toxin at four points in its 24-step life cycle, according to DNR. First discovered in 1988 by researchers at North Carolina State University, pfiesteria has been associated with fish kills and problems in coastal waters from Delaware to North Carolina.
Pfiesteria is believed to move into one of its toxic stages when certain conditions are right, including large number of fish in the water. It's also more likely to happen during the hot summer months and in high-salinity areas, Mr. Michael said. The toxins produced by pfiesteria make fish lethargic and break down fish tissue, according to DNR.
The toxic outbreaks usually are brief - perhaps a few hours - then pfiesteria returns to its non-toxic state. The ephemeral nature of the toxin release makes it difficult to capture and study.
People also reported health problems after having direct exposure to the pfiesteria toxin, with the symptoms including skin irritation, memory loss, nausea and other problems. Watermen and scientists were among those who reported illnesses they suspected were linked to pfiesteria.
With much uncertainty and scary assertions about pfiesteria, it created a perfect storm for panic, said Dr. Jack Greer, assistant director of the Maryland Sea Grant College in College Park.
Dr. Greer's staff produced a retrospective on pfiesteria last fall that included articles in Chesapeake Quarterly magazine and a documentary titled "The Pfiesteria Files."
"One of the things that makes a story take off is uncertainty ... With pfiesteria, that level of uncertainty played a big role in the firestorm," Dr. Greer said.
Some watermen and residents thought there was a cover-up, that state officials were minimizing the problem. Others thought things were overblown.
Mr. Sieling, the seafood official, was in the "overblown" camp: "I actually said at one point I would swim naked down the Nanticoke River to prove it was not something to be afraid of," he said.
At one point, grocers briefly stopped stocking Maryland seafood. People stopped buying seafood, and charter captains had fewer customers. All told, the economic damage was $43 million, according to an analysis.
"The story became very big, very fast," Dr. Greer said.
But as quickly as pfiesteria became a household word in Maryland, it disappeared from the lexicon almost as quickly.
In September and October of 1997, The Capital had a headline on pfiesteria nearly every day. Over the winter, there were about a dozen stories each month. The summer of 1998 saw only a handful of stories.
Mr. Sieling, who was the state's seafood marketer at the time, said once summer ended and the weather turned cold, people's attention drifted elsewhere.
"People just got fed up with it after awhile," said Mr. Sieling, who now is director of a trade group called the Chesapeake Seafood Industries Association.
There hasn't been an outbreak of pfiesteria toxins since 1997.
"We haven't seen any more toxic outbreaks that we could contribute to pfiesteria," said Mr. Michael of DNR.
There have been blooms of other harmful species of algae, such as a prorocentrum bloom that killed underwater grasses in 2000, Mr. Michael said.
And an algae called karlodinium was the culprit in fish kills last summer, including 15,000 dead fish in Annapolis' Weems Creek.
Though toxic pfiesteria hasn't been seen, its effects linger - some say in good ways.
Maryland officials turned their attention to agriculture. Excess nutrients running off farms can contribute to the growth of all forms of algae in the water, not just pfiesteria.
The algae feed on the nutrients - nitrogen and phosphorus - and grow. When the algae bloom, they block light from reaching vital underwater grasses. And when the algae die, they suck life-sustaining oxygen from the water.
The state required farmers to submit nutrient management plans detailing their use of fertilizers. Farmers bristled at the rules, but they've helped reduce excess nutrient runoff.
Money was poured into research on pfiesteria. The multi-state coordination of research and monitoring that was formed during pfiesteria hysteria continues today. Just this week, American and international experts gathered in Annapolis for a meeting on harmful algae blooms.
And DNR expanded its monitoring program for pfiesteria and other types of harmful algae. To this day, DNR staffers keep an eye out for pfiesteria - even though it hasn't ever again produced its harmful toxins.
"It was kind of a wake-up call that we need to do more," Mr. Michael said.
"Of all the things that came out of it, that is a sliver lining," said Dr. Greer of Sea Grant. "We are so much more attentive."
(Revised April 2008)