by Colin Perkel
Nor is it an everyday event that patients arrive with bloody diarrhea. To have two at the same time is rare, even in big-city hospitals, and pretty well unheard of in Owen Sound. Hallett found seven-year-old Aleasha Reich in the emergency department. Examining her was difficult because they could barely get her out of the washroom. Aleasha had come home from Mother Teresa elementary school in Walkerton with stomach troubles two days earlier. Her older sister, Amanda, developed a fever and cramps the same night. On the Thursday morning, Cathy Reich phoned the school again to let them know her kids wouldn’t be in, and the secretary mentioned that about twenty kids were sick. When Aleasha developed bloody diarrhea and started throwing up, Cathy took her to the emergency department in Hanover, where her family doctor practises. The hospital initially suspected a virus and sent them home with instructions to drink lots of fluids. By the evening, she was much worse. This time, Aleasha saw Panabaker. He suggested Cathy drive her to see Hallett right away. Like the boy now resting on the ward upstairs, Aleasha didn’t complain much, miserable as she was. Adults complain much more, Hallett thought.
There are half-a-dozen infectious causes of such symptoms, and the doctor, not long out of her pediatric residency, still knew them by rote: salmonella, shigella, campylobacter, E. coli…The symptoms, however, pointed most squarely in the direction of E. coli O157. Besides, Hallett had seen one case before, not six months earlier.
—
Little more than a century ago, not too many years after Joseph Walker first gazed upon the valley that would become home to Walkerton, a renowned German pediatrician and microbiologist named Theodor von Escherich identified the bacteria found by the billions in intestines of humans and other mammals. In his honour, Escherichia coli were named. Newborn babies, emerging as they do from a sterile environment, only come into contact with E. coli after birth. Within days, the hardy bacteria, which live with or without oxygen essentially feeding off whatever they find, colonize the infant gut. There they live, multiply every twenty minutes or so, and die – a cycle that repeats itself for as long as their new host survives. For anyone who cares to count, a gram of human feces might turn up about 100 million of these bacteria. Among the most primitive of all life forms, E. coli are normally benign. In fact, they are essential to our well-being, helping us to synthesize certain beneficial vitamins. But bacteria are susceptible to bugs themselves, killer viruses that invade their delicate plasmic skins, where they multiply until the host bacterium explodes like an overblown balloon. Somewhere, sometime in the past, just such a virus infected an E. coli bacterium, but instead of killing it, the invader left behind its unwelcome signature: genetic instructions on how to produce the potent poison known as verotoxin or Shiga toxin. A mutant killer bacterium was born.
—
A visitor turning off Durham Street with its rows of tidy stores soon finds himself on quiet, tree-lined streets flanked by bungalows and two-storey homes interspersed by almost stately yellow-brick houses that date to the Victorian era. There is scant evidence here of the 1980s building rush that saw subdivisions of identical houses mushroom in and around the sprawling cities and towns of southern Ontario. Still, there is little in this pleasant, residential area that gives away the fact that this is just a good-sized village. An easily missed dot on a map, where people know their neighbours and their neighbours’ kids, who deliver newspapers from wagons they pull behind them. Only the occasional whiff of freshly strewn manure wafting over from the farms surrounding the town or a tractor or combine rolling down the main street pegs this as an agricultural area.
Provincial police Const. Jamie McDonald and his wife, Cathy, a fellow officer he’d met on the force, moved from their rural home in 1997 to take up residence next door to Bob McKay. The move was intended to broaden the social horizons of their two small children, escape the hassles of caring for a septic tank and private well, and be real close to work at the police detachment in Walkerton. From their yard, the McDonalds often saw Stan Koebel cutting the grass in his own small backyard across the street. It was a perfect spot and the couple planned to spend the rest of their days there.
Thursday, May 18
6:30 P.M.
Jamie McDonald headed down to the drugstore to get some medicine for three-year-old Kylie, who had come down with a nasty bout of diarrhea.
“Oh, your kids have it too?” remarked pharmacist Ken Brown. “They are just dropping like flies all over town.”
Kylie’s five-year-old brother, Ian, would soon be suffering the same affliction.
Thursday, May 18
8:30 P.M.
While young Aleasha Reich was stuck in the washroom, Dr. Kristen Hallett chatted with her mom in the hallway as she tried to puzzle out the cause of the illness. She asked what school the girl attended, then called from emergency to the ward nurse to have her find out where the boy, admitted earlier, was from. Both, it turned out, were from Walkerton. Both were students at Mother Teresa, although in different grades and they didn’t know each other. Given that E. coli O157 is usually food-borne, Hallett quizzed Cathy Reich about what her kid might have eaten. Had there been some kind of potluck dinner, a school trip, perhaps? She ran through all the possibilities that sprang to mind, but no link jumped out. Normally, staff simply flush a patient’s stools away and give the pediatrician a general description, but because she happened to be in the hospital, Hallett asked the nurse to save a sample so she could take a look herself. They immediately struck her as “funny similar,” as if they’d come from the same person. During her conversation with Reich, Hallett noted that E. coli is sometimes found in water, but then usually only in Third World countries. Soon after, Reich’s sister came over to the hospital to keep them company. As they talked, the big storm of the previous Friday came up.
“Oh my God,” Reich said. “I hope nothing got in the water when the flooding hit.”
Returning home that evening, Reich’s sister phoned the local police detachment where she worked. A colleague mentioned she also had a child with symptoms similar to Aleasha’s. In light of her chat with Cathy in the hospital, she suggested it might be the water. A small-town grapevine began humming.
With both young charges admitted and under hospital care, Hallett headed home. While she strongly suspected E. coli O157, the possibility of poisonous drinking water didn’t enter her mind. Nor did she consider the possibility that she was witnessing the vanguard of a larger epidemic. With the exception of Panabaker, none of the area’s family doctors or other hospitals had called to say they were having a run of sick children. Still, she was baffled by the circumstances that had brought these two youngsters under her wing. Something was definitely wrong.
Friday, May 19
8 A.M.
As she made her morning rounds, Dr. Hallett was challenged by a nurse, who had overheard the parents of the two sick children talking.
“There’s more people getting sick in Walkerton,” the nurse told Hallett. “And they’re getting antibiotics.”
“We can’t treat them until we know what we’re treating,” Hallett replied, her voice gentle but emphatic.
Antibiotics are contraindicated in cases of E. coli poisoning, and Hallett considered calling the Walkerton hospital to advise against their use. That would be presumptuous, she thought, given she had no way of knowing what was ailing those patients. But word of the other cases roused her suspicion that some kind of outbreak was occurring. Moreover, she worried that patients were being treated wrongly out of panic.
From her involvement in its sexual health clinic, Hallett knew some of the people at the public-health unit, whose red-brick building sits almost directly behind her office. But never before had she called them to report a suspected disease outbreak. She walked over to the ward telephone and called Dr. Murray McQuigge, the region’s medical officer of health. He wasn’t in. Hallett decided against leaving a voicemail and was put through to his executive assistant, Mary Sellars, a helpful woman who had joined the unit as a full-t
ime staffer a month earlier. Hallett briefly explained the situation and outlined her reasons for wanting McQuigge to consider investigating the possibility of an infectious-disease outbreak.
“Do I need to call him right away?” Sellars asked.
“No,” Hallett replied, adding she just wanted the doctor to be aware that something was going on.
“I’ll let him know. I’ll put a note on his desk.”
—
Roughly eight decades after Theodor von Escherich first identified E. coli, scientists unmasked the potentially lethal rogue mutant during an investigation of an outbreak caused by undercooked hamburgers: E. coli O157:H7. The O denotes the bacterium’s specific type of surface; the H denotes its type of flagella, the tiny spiral-like protuberances that allow the bacterium to swim toward a food source. There are 170 O serogroups, as they’re known, and many more combinations of O and H serotypes. Most are harmless. Not O157:H7, which is resistant to the stomach acid that kills its close but helpful cousins. The bacterium has an uncanny ability to latch on to the insides of the intestines, where it essentially dissolves the inner lining of the large bowel, creating a direct path to the victim’s bloodstream for its deadly verotoxin. Whereas it might take 100 million other bacteria to cause disease by the intestinal route, just a dozen or so of the mutant variety can cause ghastly illness or death. It takes anywhere from one to eight days for those unlucky enough to be attacked to become ill, although symptoms typically show in three to four days. Raging diarrhea that lasts for up to ten days, sometimes longer, often turns bloody after about twenty-four hours. Excruciating abdominal pain, which suggests an inflamed or burst appendix, along with an absence of high fever typically caused by other stomach bugs, provides a telltale sign of the inner havoc being wreaked as O157 begins to spill its poison. The toxin itself does terrible damage to the cells lining the smallest blood vessels in the body, causing minuscule blockages that deprive the tissue of oxygen and nutrients. Dying tissue is what causes the agonizing pain characteristic of the illness. The damage to the blood vessels also causes blood and fluid to leak into the wall of the colon and stool, resulting in the bloody diarrhea. But what makes E. coli O157:H7 particularly frightening is that its poison, now being pumped by the heart through the bloodstream around the body, can find its way to distant organs, such as the kidneys.
There, the verotoxin destroys the lining of the millions of tiny blood vessels that act as filters to produce urine. Red blood cells forced through the damaged vessels are themselves damaged, causing almost instant anemia as internal oxygen levels begin to fall. The patient turns pale and the eyes puff from the buildup of fluid as the injured kidneys struggle to cope with the poisonous assault.
Roughly 15 per cent of those infected with E. coli develop the constellation of these symptoms that make up hemolytic uremic syndrome (HUS). Children, especially those around two years of age, and the elderly are particularly susceptible. Antibiotics don’t help and may actually make things worse. All doctors can do is keep the patient hydrated. In about half of HUS cases, blood-cleansing dialysis is needed to replace the kidney function. Still, most of the time, the body eventually fights off the infection and expels the poison by itself. The damaged blood vessels repair themselves and the patient recovers fully. For an unlucky some, though, the damage is permanent. About one in ten children who recovers from the onslaught develops problems later in life as their scarred kidneys fail to grow properly. For them, regular dialysis or a transplant may become the only alternatives to death. Some don’t get that far. In roughly three to five of every one hundred patients who get HUS, the verotoxin produced so far away by the bacteria in the gut makes the trip to the brain, where it causes death by a thousand tiny clots.
E. coli O157:H7 also infects cattle, particularly cows, although it causes them no grief. They do, however, become shedders, sometimes for a lifetime, spewing billions of the bugs into the environment through their feces. The tough, adaptable bacteria survive well in water or soil, perhaps for up to six months at a stretch. Anything coming into contact with the infected fecal matter becomes a potential hazard. In late 1992, a massive E. coli O157 outbreak in the northwest United States was traced to bad hamburger meat from the Jack in the Box restaurant chain. Of the 732 people who fell ill, 4 died and 195 needed hospital treatment. North America had again been confronted by what commonly came to be thought of as the “hamburger disease.” Still, large outbreaks are relatively uncommon. Canada might see about seventy-five cases of E. coli–induced HUS every year, twenty-five of those in Ontario. Most are random, sporadic events, the result of consuming bad meat, raw milk, or untreated apple cider. Swimming pools and well water have also caused small outbreaks. But never before in North America had treated drinking water from a municipal supply caused the illness.
Friday, May 19
10:30 A.M.
Kristen Hallett climbed into her car for the familiar ten-minute ride back to her office. Now and again, her eyes twitched, perhaps a sign of too little sleep so common to those in her field, perhaps a sign of deep thought. Even though her young patients were both in stable condition, she was distinctly uneasy. The message is going to sit on his desk all weekend, she thought.
At age thirty-two, Dr. Hallett had already made many lifesaving decisions. She had pulled newborns from the brink of death, successfully treated kids who, by all accounts, should have died from severe internal infections. Yet the magnitude of those achievements was often submerged in the swirling emotions of parents overjoyed to learn their little ones would survive. Often, there wasn’t even an opportunity for a thank you. Mostly, the parents simply didn’t have a clue what she’d done. Yet Hallett, the mother of two small kids herself, took a quiet pride in her work. Nevertheless the decision she made as she swung into the parking lot behind her office that morning seemed to her, even in retrospect, to be unremarkable. She strode into her rooms and, while her patients waited, a little boy flying an oversized Fisher-Price airplane in the front corner by the windows, picked up the phone.
“I’m sorry for calling back,” she told Mary Sellars. “But I think that this shouldn’t sit on his desk all weekend. You have to make sure Dr. McQuigge gets the message today.”
Sellars promised to act on the request. Hallett went home that Friday of the Victoria Day long weekend to prepare for a couple of days out of town. Not for a second did it occur to her that the brief phone call she had made from her office that morning would earn her national recognition as a hero.
Friday, May 19
11 A.M.
Dave Patterson was looking forward to the Victoria Day long weekend. Less than six months from retirement, the grey-haired, bespectacled Patterson had had a long career in public health, reaching the position of assistant director of health protection at the Bruce-Grey-Owen Sound public-health unit. As he settled down in expectation of a quiet day, Mary Sellars, assistant to the head of the unit, passed on a vaguely disturbing message. A Dr. Kristen Hallett had called looking for the medical officer of health. She had wanted to talk to Dr. McQuigge about two young patients, both from Walkerton, both now in the Owen Sound Hospital. What bothered Hallett, Sellars explained, was that both patients had bloody diarrhea. While calls from doctors reporting various situations or wishing to discuss concerns were not uncommon, something was unusual about this one. Bloody diarrhea is always a red flag for doctors and those in the public health field because of its link to E. coli O157. Patterson called in Bev Middleton, one of three members of his communicable diseases team.
“Bev, I want you to listen to this,” Patterson said. He proceeded to play the voicemail message left by Sellars.
“Would you check with Dr. Hallett, please, and find out what’s going on?”
Middleton soon reported back. Staff at the Owen Sound hospital had collected stool samples for analysis. Middleton had asked that the health unit be notified as soon as possible if the hospital lab turned up any dangerous bugs in the cultures. It would take at least twen
ty-four hours for the earliest preliminary results, another day for definitive results. Given that the two youngsters were both from Walkerton, Middleton had also decided to put out some further feelers. At the Walkerton hospital, Dr. Michael Gill reported having seen eight similar cases over the past two days. No one had been admitted and no one had collected any stool samples. One of the patients coming through the emergency department was little Mary Rose Raymond, whose diarrhea had turned bloody. She was also throwing up. She was sent back home to Hanover with a prescription for an anti-nausea medicine and hydration formula.
Friday, May 19
Noon
It had been one of those days for Stan Koebel. He’d spent the morning up in Southampton at yet another meeting about a proposed amalgamation of several area electrical utilities. His counterpart from Hanover was driving them back when Stan’s cellphone rang. It was Janice Hallahan, who told him that James Schmidt of the public-health unit’s office in Walkerton had just contacted her.
“It’s regarding some calls that I’ve received about some people being sick and I just wanted to talk to Mr. Koebel about that,” Schmidt had said.
After being dropped off, Stan climbed into his truck and called Schmidt, who told him that children from Mother Teresa had come down with diarrhea and stomach cramps.
“Is there anything with the water?” Schmidt asked.
“I don’t think so,” Stan said. “I think the water’s okay.”
“Yeah, well, just checking,” Schmidt said. “Probably just the flu or some bad food or something.”
Stan was bothered. What was that about? No one from the Environment Ministry had called. Nor had he heard anything from the lab regarding the new set of samples from the water-main project, which had fallen still further behind schedule. Then again, the main wasn’t even hooked up to the system. He tried to remember what was on the other fax, the one showing the bad samples in the town’s taps. But perhaps because the notion that the water could somehow be to blame was too terrible to contemplate, he filed the idea away in the back of his mind and headed over to the construction site on Highway 9. To his dismay, Frank told him that they’d connected the main to Saugeen Filter Supply and had already cracked the valve to allow water from the town’s distribution system to fill the new main. No one would be drinking the water until the tests on the new main came back clean, Frank explained. Stan frowned but said nothing.