Aquatic botanist JoAnn Burkholder prepares 70 fish per day to be sacrificed to the strange beast in her lab aquariums. To the naked eye, the tanks appear empty, but 10 minutes after Burkholder places the fish in the water they are all dead. Some fish are covered with hideous sores that caused scientists to label their microbial murderers as "the cell from hell."

Burkholder knows too well that the beast's venomous "bite" can harm humans as well as fish, so she watches the slaughter from behind a mask and protective suit. The "creature" is a bizarre one-celled predator that can transform itself from animal to plant to animal again.

This killer dinoflagellate-Pfiesteria piscicida-came on the scene six years ago in North Carolina's coastal estuaries. It is the suspected killer of more than one billion fish.

Six years ago the tiny creature seemed exotic and weird. But, after many investigative studies over the past six years, it is no longer viewed as a curiosity; it is now a warning. Now scientists place the Pfiesteria among the ranks of other harmful microorganisms, including the toxic "brown tides" that have devastated fisheries in New England and Texas by polluted sewage-filled waters.

According to scientists, "Pfiesteria may be another sign that humans are changing coastal environments in ways that could have serious consequences for wildlife and people ..." (Joby Warrick, The Washington Post, June 10, 1997). There is little doubt that this cell from hell has the same effects as that known as plague. It can neurologically impair human beings, causing symptoms that can include open sores, nausea, memory loss, fatigue, disorientation and a near-total incapacitation (Michael Satchell, U.S. News & World Report, July 28, 1997, p. 27). It is a plague and, according to Satchell, it is spreading.

We can add Pfiesteria to the list of other newly discovered killers that have made headlines in recent years-AIDS, Ebola, Lassa fever and hantavirus, among others.