The Blue Death

by Dr. Robert D. Morris

  On April 3, his first morning out of the hospital, he awoke to bright sun streaming through the window. He had every reason to feel optimistic, but as the day wore on, the feeling was shattered. Painful cramps racked his body and he began to vomit. He searched for an explanation. Perhaps it was from the drugs he was taking to help him survive the bone marrow transplant. Then the diarrhea hit him. Wave after wave. This was not going away. He would soon find himself back on the wards of Milwaukee County Hospital, a return that was both physically and mentally excruciating. Although he had no way to know it, Mark Rahn was not suffering alone.

  In the nearby suburb of Wauwatosa, Tom Taft and his wife had already been ill for several days. They had spent much of the preceding week suffering from intense cramps and profuse diarrhea. Most people would have simply gritted their teeth and waited for the illness to subside. Tom Taft was different—as an infectious-disease physician he wanted to know what had hit him. And how it had found him.

  High on Dr. Taft’s list of possible sources was a dinner the couple had attended at Milwaukee’s Italian-American Community Center. Community gatherings and picnics are notorious for their capacity to cause small outbreaks.

  Dr. Taft then discovered that his case was far from isolated. Over the course of the week that he was ill, he had begun to receive calls from colleagues at West Allis Hospital asking him to consult on patients who were hospitalized with severe diarrhea. In each case the standard tests had failed to find the organism responsible. The fact that doctors had no lead on the pathogen meant they could only guess at how to treat the disease. Antibiotics did nothing. Their best bet was to help their patients find a way to replace the fluids they were losing because of the intense diarrhea. All over Milwaukee, doctors offered their patients the same advice. Drink water. Drink plenty of water.

  By Sunday the hospital was flooded with patients. As he consulted on some of the most severe cases, Tom Taft sensed that he might be seeing the tip of an epidemiological iceberg. For each patient he was seeing, how many more were out there? How many were going to other hospitals or being treated by their doctors and sent home? How many were just starting to get sick? How many would start to get sick tomorrow?

  It was the weekend. Snow, ice, and slush covered the sidewalks and streets. When Liz Zelazek went out that Saturday, she assumed that the weather was the only thing keeping people off the streets. Then, late Sunday, she turned on the news. It had been a slow news day, but a story carried by one channel caught her attention. Several Milwaukee drugstores had been stripped of their supplies of Imodium and Kaopectate, over-the-counter drugs used to treat diarrhea.

  Later that night her sister called. When Zelazek mentioned the news, her sister expanded on the story. She had just been to the drugstore and the shelves that normally carried medication for diarrhea were empty.

  Zelazek made a mental note to herself to mention this report when she arrived at work the next day. As the director of public health nursing for the city, finding the reasons for this apparent run on medication might even become her first task for the next day.

  Fifty thousand years ago, vast glaciers, some more than a mile thick, crawled across North America, tearing away pieces of the land as they came. Then, twenty thousand years ago, the ice began to melt. Like geological toddlers, when the glaciers retreated from southern Wisconsin, they left behind a messy jumble of earth and stone now known as the Kettle Moraine because of its pockmarked blend of hills and hollows. Today the farm town of Eden, Wisconsin, sits in the Kettle Moraine, seventy miles northwest of Milwaukee. Just to the east, in a small valley, a river begins.

  The river once wandered through virgin forests of beech and basswood, past dense stands of sugar maples and under the shadows of ancient oaks. The Potowatomi came to eat the fish that thrived in its cool waters and hid in the hollows of its many tributaries. Over time the forests fell to the axes of farmers who had come to brave the wild western frontier of a young America. First the French, then the British, then the Germans all came to stake their claim, strip away the trees, plant crops, and raise livestock.

  As immigrants came they built the farm towns that hang on the river like so many beads on a string. From Eden, the river winds south and east past Campbellsport, Kewaskum, and West Bend, past Newburg, Waubeka, and Fredonia. It scrapes along a limestone bluff, just a few miles from Lake Michigan, through Saukville and Grafton, Cedarburg and Thiensville. Then the river finds its outlet. At a break in the limestone, the river makes a final turn to the east and empties into the vast fresh water sea of Lake Michigan. That estuary and the bluff above it formed a favorite spot for the natives who called it simply milwaukee, the gathering place by the river.

  The river itself also came to be known as the Milwaukee. Just before its mouth, two rivers add their waters, the Menomonee from the west and the Kinnickinnic from the south. All three rivers slow and widen as they approach the lake, and as they do, the rich topsoil suspended in their current drops to the bottom. Dense fields of wild rice once rose in this lush estuary.

  As the city of Milwaukee grew, the river that had attracted people to its banks as a source of food and water grew foul and lifeless. By the twentieth century, the river had become an industrial shadow of its former self. Today the estuary has long since disappeared beneath layers of fill. A lattice of train tracks runs where wild rice once grew.

  The Menomonee River, together with the tracks that follow its course from west to east, splits Milwaukee in two. When Polish immigrants arrived in the city in the early twentieth century, they settled the low-lying, marshy area south of the river. On a high bluff facing Lake Michigan, they built St. Stanislaus Catholic Church, the first Polish church in any American city.

  In time new waves of immigrants brought new faces, new names, and new cultures to the pews of St. Stanislaus and built other, smaller Catholic churches in its shadow. First Serbs, then the Irish and Italians, and later an influx of Hispanics filled the homes and factories of Milwaukee’s south side. Their children came to learn at the district’s parochial schools. On that first Monday morning of April 1993, these schools were among the first to register the effects of the outbreak. One of them, St. Adalbert’s Parish School, announced that it would not open. The school could not find enough healthy teachers to run its classes.

  In nearby West Allis, school administrators spent the morning on the phones scrambling to find substitutes as teachers called in sick. They soon discovered that the substitutes were sick too. They then made plans to combine classes in order to accommodate all their students. Oversize classes would be better than no classes at all. They need not have worried about class size; when the school did open, a quarter of the students never arrived. They were home sick.

  On the other side of the Menomonee River, Paul Nannis was already at his desk in a spartan office on the first floor of the city’s municipal building. He had risen early that morning and eaten breakfast as his two cats prowled among his jungle of houseplants like leopards in the rain forest. As always he had spent part of the weekend in his office, catching up on work in the unruffled quiet. Like most of his senior staff at the Milwaukee Health Department, he had not seen the news the night before and had no idea of the events unfolding around the city as he headed out into the cool, gray morning. By seven-thirty he was hard at work as Milwaukee’s health commissioner.

  In a cramped lab two floors above, Gerry Sedmak practiced the art and science of growing viruses. Most bacteria are easy to grow, as they require little more than a dish full of food and a warm place to reproduce. Viruses, on the other hand, are far more finicky. To grow them Sedmak needed a cell that the virus liked to infect and a way to grow those cells. As they grew he would add a sample from a patient and, if the virus were present, it would infect the cells. As he arrived on Monday morning and began to check on the various cultures running in his lab, the phone rang.

  Whenever a new bug seemed to be making the rounds, Milwaukee’s medical reporters knew to suspect a vi
rus. One of them had picked up on the television news story and wondered if something was brewing. As the city’s virologist and an affable source for the press, Sedmak was the go-to guy for viruses. He usually knew what viruses were working their way around Milwaukee, but nothing growing in his lab could explain the run on Imodium. Before long, a second reporter called. Dr. Sedmak didn’t have a ready answer. As soon as he hung up, he called Paul Nannis.

  Nannis didn’t like to see information flowing uphill. He did not want to learn about a possible outbreak from the news media. Whatever was happening, news needed to start flowing downhill and fast.

  Nannis could not even begin to unravel this mystery on his own. The first nonphysician to run the city’s health department, he had been chosen for the job because of his skills as a manager and communicator. His job was to know how and when to bring the resources of the department to bear on a problem. Nannis began typing a note to Steve Gradus, his laboratory director.

  Nannis relied heavily on Gradus, but the two men inhabited separate hemispheres in the world of public health practice. Nannis worked in the land of education, communication, politics, and public relations. Gradus operated, for the most part, out of the public eye, in a world of science, not convention; a world of logic, not nuance. A self-effacing, highly skilled microbiologist, Steve Gradus loved the quiet refuge of his laboratory.

  Gradus was looking through his e-mail from behind a thick brown beard and a pair of horn-rimmed glasses when he got the note from Nannis. As he read it, he was not sure what to make of it. Perhaps this was much ado about nothing, a twenty-four-hour virus making the rounds of a neighborhood. On the other hand, it could be the opening salvo of a significant outbreak. The challenge of cornering an unknown pathogen amid the glassware, reagents, and microscopes kept him coming to work each day. But it would take some time before he could begin to hunt for the cause in his own laboratory. For the moment his most important laboratory instrument would be a telephone.

  He needed to collect his own data. If a few dozen people were staying home with diarrhea, he had something mild on his hands. If they were going to the hospital, he had a more dangerous pathogen to worry about. The directors of the microbiology laboratories at hospitals around the city would tell him whether or not this was a significant outbreak, and if so help him determine its size and location. His first call made it clear that this was real and serious. The lab at St. Luke’s Hospital, one of the city’s largest, had been so overwhelmed with requests to test stool samples that they had run out of culture medium.

  If a single hospital was seeing a large number of cases of debilitating diarrhea, Gradus’s public health training and experience told him that a local restaurant or a picnic or banquet might well have been the source the disease. Spoiled or contaminated food frequently causes sudden, localized outbreaks. With his second phone call, however, the picture changed.

  The second lab director told Steve Gradus the same story as the first. The weekend had brought a run on stool cultures. With at least two hospitals involved, the possibility that a single restaurant had caused the outbreak faded. Perhaps a chain of restaurants or a major food supplier was distributing tainted food. Maybe spectators at a Bucks game or the Frozen Four (the final rounds of college ice hockey’s national championship, which had recently been played in Milwaukee) had been hit by undercooked bratwurst.

  Gradus needed to consider other ways by which this disease might be spreading. It could have passed from person to person. An unwashed hand, a dirty doorknob, or a shared sip of soda could all transmit diarrhea. However Gradus knew that diseases spread in this way tend to cause slow-moving outbreaks. It seemed, for the moment, that this one had spread too far, too fast.

  Another alternative, an airborne virus, could cause a sudden, widespread outbreak. Milwaukee had seen that happen a few years earlier when inadequate vaccination levels had allowed a measles outbreak to take hold. But airborne spread requires something to launch the virus. Only after a cough or a sneeze sends millions of viral particles hurtling through a room full of potential victims can a virus touch off such an explosion. In other words, if the outbreak were airborne, Gradus would see respiratory symptoms among at least some of the victims.

  To narrow the list of possibilities, Gradus needed more data. He needed to know who was getting sick and what kind of symptoms they were experiencing. He continued calling other labs around the city and began calling emergency departments as well. As they did so, the outbreak began to tell its own story. Few of the patients had coughs, so this did not appear to be airborne. It also did not seem to spread by personal contact.

  As any parent knows, children are the perfect vector for the spread of disease from person to person. If the disease was occurring predominantly in children, the outbreak could be spreading through the schools. As the two microbiologists called around the city, however, they learned that Children’s Hospital had not been particularly hard hit. Their other calls suggested rather that adult males were showing up at hospitals in large numbers, hardly the demographic of a preschool outbreak. If the disease was striking disproportionately at adult men, a large public event like a sporting event could be its source. Gradus and the city epidemiologist would need to investigate recent events to look for a source.

  Kathy Blair (then Fessler) had not started out to become an epidemiologist. She began her career as a nurse in the neonatal intensive-care unit, but the long late hours became more than she could handle. She joined the health department as a public health nurse with the expectation that she would have a more manageable schedule. She hadn’t counted on the month of grueling days that lay ahead.

  Blair had almost no formal training in epidemiology; she had learned on the job by assisting Tom Schlenker, the city’s medical officer. As small outbreaks hit Milwaukee, she had worked with Schlenker on the search for their cause. She learned quickly, and when, in 1988, Nannis decided that the city needed an epidemiologist, Schlenker appointed Blair to the job, a decision that was about to be put to the test. Blair would have primary responsibility for the epidemiological analysis of this outbreak.

  By the time Liz Zelazek poked her head in the door that morning to tell her former nursing colleague about the report she had seen on the evening news the night before, Blair had already gotten word of the outbreak from Paul Nannis. Her first reaction was to try to find its boundaries. As Steve Gradus called labs and emergency rooms, she called an epidemiologist at the Wisconsin Department of Public Health. She described the cases that were occurring in Milwaukee and asked if anyone else in the state was seeing anything similar. Milwaukee, she learned, was alone.

  As news of the outbreak filtered into the health department that Monday morning, Gradus and Blair met with Schlenker to assess the situation. Initial reports suggested that the outbreak had begun five to seven days earlier and had grown slowly before exploding over the weekend. They still had limited information about the number of cases, but during the weekend a single, small emergency room at St. Francis Hospital had seen 145 patients weak and severely dehydrated. Worst of all it appeared that the outbreak might still be growing.

  If the disease was still spreading, their task took on a new urgency. Every moment that passed until they identified the source meant more cases. They knew that many of those cases were severe, even life-threatening. Any lost hours could mean lost lives.

  Finding the pathogen would take them a long way toward solving the puzzle, but the hospital labs hadn’t given them much to work with. They had all tested for bacteria using bacterial cultures similar to those developed by Robert Koch more than a century before. Those tests take forty-eight hours to produce definitive results, but preliminary results were negative. The standard O&P (ova and parasites), a microscopic search for protozoa and parasitic worms had been negative. Viruses can also cause waterborne disease, but physicians did not routinely order tests for them since the tests were cumbersome and effective treatment did not exist. The few viral tests that had been ord
ered were also negative.

  If these results were correct, the hospital labs had either missed something or simply failed to turn over the right stones. Steve Gradus made plans to get samples from hospitals around the city to run his own tests. Blair, working with Gradus, Schlenker, and the state epidemiologist, laid out a plan to begin gathering the epidemiological data that they would need in order to isolate the source of the outbreak.

  As they advanced their epidemiological dragnet, one explanation could not be ignored. Even though it seemed unthinkable for an American city in 1993, they had to consider the water supply.

  At the time of its creation in 1874, drinking water quality had been a core responsibility of the Milwaukee Health Department. The first laboratory tested only two things: water and milk. In 119 years much had changed. Water quality was now the province of engineers and chemists in the Department of Public Works (DPW). Even though the DPW occupied offices just one floor above the public health laboratories in the municipal building, the two departments had nothing that could be called a working relationship. Except for following up on the occasional call from citizens concerned about their water, the health department had had almost nothing to do with the water supply.

  The DPW maintained its own labs for testing water. They no longer relied on the health department, but they did have a responsibility to notify the health department if the drinking water had violated federal standards. There had been no such notice. Assuming there were no problems in the lab and regulations had been followed, a waterborne outbreak seemed unlikely. Nonetheless they needed to be sure.

  Milwaukee draws its water from the vast reservoir that is Lake Michigan. Its waters were once so pure a fish could be seen as much as eighteen feet below the surface. Although it no longer had such crystalline purity, the lake was (and is) far cleaner than many other big city water supplies. Two water treatment plants supply the vast network of water pipes that runs beneath the city streets. The Linnwood Treatment plant, a grand, New Deal–era public works project, sends water into those pipes from the north. Water from the Howard Avenue plant, a more recent and less inspired facility, fills the network of pipes from the south. The two supplies meet and mix somewhere in the vicinity of the Menomonee River.