Ancient ideas about demons have now given way to fears about toxics in our food, our water, and our air, fears often triggered by a strange odor. Since the gas warfare of the First World War, fears of toxic gasses — rather than any actual gasses — have been implicated in a number of prominent mass illnesses. After the anthrax episodes that followed 9/11, an epidemic of mysterious rashes showed up in elementary schools in half a dozen states around this country.

As a working hypothesis for the complaints along the Pocomoke, "Pfiesteria hysteria" made a certain amount of sense. The illness usually takes one of two forms, according to Simon Wessley, a psychiatrist who has written widely on the disease. "Motor hysteria" includes twitches and spasms and strange speech, the kind of symptoms once found among nuns and witches. A second form called "anxiety hysteria" includes headaches, dizziness, nausea, shortness of breath, and general weakness — and nearly all these symptoms were cited by watermen exposed to the Pocomoke River.

The medical expedition that Glenn Morris was leading down to Somerset County was, in many ways, a classic contemporary response to a potential mass hysteria event. According to Tim Jones, writing in the American Family Physician, the best ways to halt mass psychogenic illness are to perform medical exams, provide credible reassurances from respected authorities, and spread the word there is no health problem. "Our major objectives," Morris told his team during the bus ride, "are to try to relieve anxiety and reassure everybody that everything is fine."

When Glenn Morris and his team arrived at the Somerset County Health Department, nearly twenty television trucks were in the parking lot pointing satellite dishes at the skies, and reporters and cameramen outnumbered patients nearly four to one. Morris began a day of medical exams by putting on his white doctor's coat and holding a press conference.

He told the press throng that the doctors came from both the University of Maryland and Johns Hopkins University (only one physician represented Hopkins). The two-school strategy was the idea of Marty Wasserman, then Secretary for Health and Mental Hygiene, who said he didn't want one Maryland medical school criticizing the other in the press. Often blamed in the medical literature for extending mass hysteria, the press could now perhaps help in spreading the word. A clean bill of health from a two-school team — widely reported in the press — could help calm the mounting anger and panic along the Pocomoke.

By the time he'd talked to five patents, Morris began to change his mind about his hysteria hypothesis. Medical care begins with narrative, with the patient's oral history of his problems, and all the examining doctors kept hearing story after story about forgetfulness and mental confusion.

The medical team examined 13 people that first day in Somerset County: seven watermen, the wife of a waterman, four state workers and one water-skier — and nearly all of them reported the same odd symptoms. There's something going on here, thought Morris.

Lynn Grattan climbed on the van that August morning, carrying briefcases full of mind games. A neuropsychologist with the University of Maryland School of Medicine, she would be screening for any brain misfunctions that might lie behind all those odd stories of memory lapses. Her job was to use science to investigate storytelling — and she had 14 tests ready.

Grattan culled these tests from the array of psychometric tests used to uncover unusual brain pathologies. Some screens could assess language and visual/spatial abilities. Others could test cross-brain connections and problems with concentration and divided attention. Several could probe memory and mood, including anxiety and depression. Many of the tests had questions designed to dig out symptom faking and exaggeration.

As she worked through the day Grattan was not listening closely to the stories her patients told. She spent her time setting up tests, asking questions, recording answers, measuring response times — in short, taking data. She wouldn't make much sense of that data until she could go back and score all the tests.

By the time she climbed on the van for the ride home, all the doctors were buzzing with talk about the stories they'd heard. Like university researchers everywhere they were jazzed by the idea of a new discovery, a new syndrome for the medical literature. It's one of the reasons you do science, Morris liked to say, finding something new. They kept the lights on in the bus, tabulating data all the way back on the long drive up the Eastern Shore and across the Bay Bridge.

The only one who wasn't talking much was Grattan. As the neuropsychologist for the group, she didn't want to say anything until she could work through all her data.

Lynn Grattan sat down at her kitchen table at 5 a.m. the next morning, a Saturday, and went to work scoring her tests. By early afternoon she was able to call Morris, the team leader, with some disturbing findings. Out of 14 screening tests, nearly everyone was performing poorly on the same three tests. The Stroop Color-Word Test was one. It starts with a list of words, each naming a color, but then adds a twist: The word "red" might be printed in the color green, while the word "green" might be printed as purple. "What's that color? she would ask, pointing at the word "green." The correct answer, of course, is purple, but it's easy to feel a disconnect, to hesitate. If you hesitate a lot, you could have a slow connection between the right brain (which processes color) and the left brain (which handles words). You could have a problem with divided attention.

A second test — called the Grooved Peg Board Test — also measured cross brain connections, concentration, analytical skills as well as manual dexterity — all on a timed trial.

The strongest findings came from the simplest test. With Rey's Auditory Learning Test, Grattan would show her patients simple, unrelated words (BELT, RAIL, FORK, INCH) one at a time — then ask them to recall as many words as they could. Later in the evaluation, she would suddenly ask her subjects to recall the first list again.

The scores on this widely used test were startling. When she checked the normative data base for this test, a collection of scores from hundreds of thousands of people of similar age and occupation who had answered the same questions, she found nearly everybody scored better — much better than the people from the Pocomoke. Those with moderate exposure to the Pocomoke were scoring near the bottom eight percent on word recall. Those with high, nearly daily exposure to fishing areas along the Pocomoke were scoring in the lowest two percent for their age and occupation.

Grattan told Morris she was seeing evidence of a clear, consistent pattern of cognitive deficits. The Pocomoke patients had problems with divided attention, response inhibition, and especially short-term memory. For most of us, short-term memory is the engine for new learning, the mental machinery that takes in new information — whether from a conversation, a phone call, a newspaper. She thought the results were frightening.

If it was "a Yes or No sort of question," then the answer was a Yes: There did seem to be a health effect from Pfiesteria or some other toxin in the water.

When Glenn Morris hung up the phone, he knew he was facing a classic public health dilemma.

Do you take action before you know everything about the threat? Or do you wait for more evidence, at the risk of exposing more people to the threat? If you take action, do you cause other, greater problems?

Morris solved his quandary with a question: Would I let my daughter go swimming in the Pocomoke? When he realized the answer was No, he gave Wasserman and other state officials the answer nobody wanted to hear: Exposure to river waters associated with sick fish and Pfiesteria-like organisms was somehow causing short-term memory loss. The press and the public and the politicians could drop the mass hysteria hypothesis.

Faced with this kind of finding from this kind of medical team, Maryland Governor Parris N. Glendening had little choice. On the Friday before Labor Day weekend, he called a major press conference in Annapolis. "The public must be informed of this connection to human health," he announced, and then — because of the health threat — he closed seven miles of the Pocomoke River. "There is," he added, "no reason to panic."

What followed looked a lot like a low-level panic. Newspaper and television reporters now drove down by the dozens from Washington and Baltimore and began wandering the backcountry roads around Shelltown and Nanticoke looking for locals who might be suffering memory loss. All those reporters were quickly turning Pfiesteria in the Pocomoke into a national story. More reporters then flew in from New York, Atlanta, Europe, and Asia, turning Pfiesteria into an international story.

The dream team strategy had backfired. Alerted by the press, a second wave of potential patients called in to hot lines set up by the State Department of Health and Mental Hygiene and state officials were soon listing 31 diagnosed cases.

This page was last modified September 15, 2018