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Inspiration or Obsession?

Posted By Lauren Reeves, Thursday, September 11, 2014
This week's post is the third in our series of posts about Deadly Outbreaks , a book of outbreak mystery stories, written by Alexandra Levitt. The book is available for purchase at amazon.com .

Epidemiologists who investigate disease clusters and epidemics typically work in close partnership with laboratory scientists who identify pathogens that cause outbreaks. In many cases, infectious disease mysteries are quickly solved once the causative agent is known, because public health experts know how a particular pathogen is transmitted and what can be done to interrupt its transmission. But what happens when an outbreak is caused by an unknown pathogen for which there are no diagnostic tests? Here is what happened in a real-life outbreak story recounted in Deadly Outbreaks, entitled Inspiration or Obsession:

In August of the Bicentennial year of 1976, several people died of a flu-like illness after attending an American Legion convention at an elegant Philadelphia hotel. Public health authorities suspected that the Legionnaires might be the first victims of the dreaded “Swine Flu,” caused by a new strain of influenza, identified eight months previously. However, the ensuring investigation ruled out Swine Flu and a range of other respiratory, foodborne, and waterborne diseases. Instead, the epidemiologic data suggested an airborne chemical or microbe inhaled by people who walked in front of the hotel or entered the hotel lobby. Otherwise, the investigative trail yielded no useful clues. Some said it was a Communist Plot or a terrorist attack. Others thought that the cause might never be known.

At the end of the summer, after three and a half weeks of field work, the CDC team assisting the Pennsylvania Department of Health returned home with the mystery unsolved. Public health officials had identified 221 cases of the illness, which came be known as Legionnaires Disease (LD); 34 people had died. Although the outbreak had stopped, with no additional cases identified after August 18, public worry—inflamed by the Swine Flu scare—continued unabated. CDC was criticized by politicians, journalists, and local health officials for its failure to find the cause of the outbreak, as well as its decision to vaccinate the U.S. population against a pandemic of Swine Flu—a catastrophe that never materialized.
Enter Joseph McDade, a dedicated young scientist who began as a bit player in the drama, helping to rule out an animal-borne disease called Q fever as the cause of LD. With that task accomplished, McDade turned back to his day job, which involved developing methods for the detection of epidemic typhus. For most of the fall, he was uninvolved in the LD investigation and oblivious to the ongoing turmoil at CDC—at least at first. His natural bent was to screen out all distractions and focus single-mindedly the scientific problem at hand. Nevertheless, from time to time—especially when he came up for air after completing a round of typhus experiments—he had little, niggling thoughts about some tiny rod-shaped bacteria he’d seen on a few of his Q fever slides. At the time, he had dismissed the rods as insignificant contaminants. But now he was not so sure.
As recorded in Deadly Outbreaks [page 104], McDade thought of the rods as a “hook” on which his thoughts were snagged:
McDade felt more and more compelled do something, anything! …He had to go back and look at those rods once again. He decided to make himself stop what he was doing (a whole other set of typhus experiments) and re-focus [on the mystery disease]. He knew there was little chance that he would find anything that his colleagues had missed, but he was more and more bothered by the problem, almost to the point of obsession. Instead of worrying himself to death, he decided, he would “clarify the issue” one more time and then forget about it.
Alone in the laboratory over the Christmas holiday—nearly five months after the first LD cases appeared—McDade retrieved the Philadelphia specimens from deep-freeze and set out to figure out what had really happened…

Tags:  Deadly Outbreaks  infectious disease 

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Real-life Outbreaks: Sorrow and Statistics

Posted By Lauren Reeves, Friday, August 29, 2014

This week’s post is the second in our series of posts about Deadly Outbreaks, a book of real-life outbreak mystery stories. You can purchase a copy of Deadly Outbreaks by author Alexandra Levitt at amazon.com.

Epidemiologists who investigate outbreaks often use their findings not only to control disease but also to prevent future outbreaks once the immediate emergency is over. For example, in the aftermath of an outbreak that occurred at a Toronto hospital during the 1980s (described in Chapter 3 of Deadly Outbreaks), the investigators recommended extensive changes in how hospitals dispense drugs and how they use mortality data to monitor and improve hospital care. Although public health experts had been advocating these improvements for some time, the experience at the Toronto hospital—which involved drug overdoses and a long lag before a problem was recognized—demonstrated their importance in a dramatic and unequivocal way.

Here is what happened in the outbreak story entitled Sorrow and Statistics:

In 1981, thirty-four babies at the Hospital for Sick Children in Toronto died from apparent overdoses of the heart medication digoxin. Although a judge dismissed murder charges against a nurse who had been on duty during some (but not all) of the deaths, the police continued to claim that she was guilty, while the hospital’s doctors insisted the babies had died of natural causes.

With the hospital under a cloud of suspicion, the hospital authorities called in outside help, in the form of an Epidemic Intelligence Service (EIS) officer from CDC. On his arrival, officials from the Ontario Ministry of Health introduced the EIS officer —James Buehler—to two experienced Canadian colleagues who served as members of his investigative team.

Buehler understood from the start that there was uncertainty about what they might be able to accomplish. As recorded in Chapter 3 of Deadly Outbreaks [page 63]:

“What could the medical detectives do that the…doctors and police had not already done? The doctors had focused on the details of each baby’s illness, finding a natural reason for each death. The police, on the other hand, had focused on a particular suspect, seeking legal evidence to build a case against her. The epidemiologists viewed the evidence from a different angle. Unlike the police or the doctors, they looked at all of the deaths at once, as part of a single mission, trying to figure out what all the cases had in common—somewhat like an FBI analyst examining deaths linked to a single serial killer. However, unlike the police or FBI, they were not concerned with legal issues or with questions about human guilt and motivation, and unlike the hospital staff, they bore no personal responsibility for the babies’ welfare. They did not interview the nurses or meeting with the victims’ parents. Thus, they were emotionally removed from the tiny victims and perhaps better able to analyze the data in a dispassionate way, using graphs and statistics—“people with the tears wiped away” as the EIS saying goes. Another way to say it is that they ignored the horror behind the numbers and plunged on, wherever the data would take them.”

James Buehler and his team, working as unobtrusively as possible at the troubled hospital, used epidemiologic data to confirm that a significant rise in the infant death rate had actually occurred on the hospital’s cardiology ward. Then they proceeded to collect hypotheses and rule them out, one by one, until only one was left….

Tags:  Deadly Outbreaks  infectious disease  outbreak 

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The McConnon Strain - A mysterious outbreak of unknown spread

Posted By Lauren Reeves, Thursday, August 14, 2014
Untitled Document

Despite advances in healthcare, infectious microbes continue to be formidable adversaries to scientists and doctors. Deadly Outbreaks—a book of real-life outbreak mystery stories—recounts the scientific adventures of a special group of intrepid individuals who investigate disease outbreaks and figure out how to stop them.

Several upcoming blog posts will describe stories from Deadly Outbreaks, written by Alexandra Levitt. (You may recognize some of these outbreak or their causes, or you may know some of the epidemiologists. Read on to find out….) For example, this week’s post concerns an outbreak of a dangerous drug-resistant disease with the potential for international spread. Like today’s Ebola outbreak in West Africa, the dangers posed by this outbreak underscore the critical importance of maintaining local public health systems that do the day-to-day work of investigating outbreaks and stopping them at their source. We rarely know in advance which small outbreak or disease cluster will turn out to be something truly dangerous and devastating.

Here is what happens in the outbreak story entitled The McConnon Strain:
Epidemiologists sometimes face difficult choices, with moral, political, and financial repercussions that must be weighed against risks to human health. In 1983, for example, two officials, Patrick McConnon (from the United States) and Roland Sutter (from Switzerland), agonized about whether to delay the long-awaited repatriation of 20,000 Cambodian refugees, fearing that some might carry a rare, multidrug-resistant form of malaria. The U.S. Government planned to fly the refugees from Thailand, where they lived in border camps, to the Philippines (where they would be processed for entry into the United States). Stopping the flight would prolong the misery of hundreds of desperate families eager to resettle and start new lives. On the other hand, introducing an untreatable form of malaria into a mosquito-infested part of the Philippines could bring illness or death to thousands or even millions of people. As recorded in Deadly Outbreaks (page 38):

People stranded in refugee camps, displaced, impoverished, and malnourished, are at special risk for infectious diseases such as malaria, measles, and cholera that flourish in crowded and unsanitary living conditions. When infected refugees are moved to new holding sites, repatriated, or resettled in new countries, they can bring these diseases with them. As a result, public health officials like McConnon have overlapping and sometimes conflicting aims: to safeguard the health and welfare not only of the refugees themselves, but also of the people in countries that host refugee camps or accept refugees as permanent residents.

The spread of smallpox after the 1971 Pakistani civil war illustrates what can happen when a pathogen incubated in a refugee camp infects the wider population. Smallpox was carried to the newly established nation of Bangladesh by Bengali refugees returning home from India. According to public health lore, the presence of smallpox in the camps was detected by an epidemiologist in Atlanta, sitting in his living room watching TV, who noticed a man with a suspicious rash in a newsreel about a camp near Calcutta... The epidemiologist called the director of CDC, who called the director of the WHO Smallpox Vaccination Program, who called the Indian Ministry of Health. But it was already too late. Thousands of Bengalis had already left the camp, leading to widespread outbreaks in Bangladesh and making the last Asian country to eliminate smallpox.

McConnon was well aware of this history, because he had worked in Bangladesh in 1975, the final year of the smallpox eradication effort in Asia. He tried to convince an official at the U.S. State Department that it was dangerous to send refugees to the Philippines before screening them for this unusual strain of drug-resistant malaria. But the State Department official was skeptical and demanded to see some evidence.
With few resources and little time, McConnon and Sutter conducted a small-scale epidemiologic study in the border camp. If they could figure out which activities (e.g., farming, fishing, water collection) exposed people to malaria, they might delay the departure of exposed refugees while allowing unexposed refugees to proceed to the Philippines. As part of the study, they plotted the location of each malaria case on a map of the refugee camp, hoping to see a pattern. However, the data did not support any of their hypotheses. There was no association between the malaria cases and growing crops or working near the forest, swamp, chicken coops, or garbage dump. In fact, the distribution of malaria cases seemed entirely random, except for one thing: nearly all the cases involved males between the ages of 13 and 35.
This did not make sense! The mosquitoes that carry malaria do not distinguish between women and men or between the young and the old. McConnon and Sutter remained frustrated and puzzled—until they stumbled on an explanation during a conversation in a local bar when an aid worker mentioned a border-camp activity they had not tested for…
Stephen Ostroff, MD, former deputy director of CDC’s National Center for Infectious Diseases and former director of Pennsylvania’s Bureau of Epidemiology, said that “anyone with even a passing interest in disease investigation will find Deadly Outbreaks to be a great read. So too will all practitioners of public health, from students contemplating a career in epidemiology to the most seasoned veteran.” You can purchase a copy of Deadly Outbreaks by author Alexandra Levitt at amazon.com.

Tags:  deadly outbreaks  infectious disease  malaria  outbreak 

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