Download A Case of Legionnaires

EurekaLab
Episode 1: A Case of Legionnaires
08/22/2012
You’re listening to EurekaLab, a Charles River Lab production, written and recorded in
Wilmington, Massachusetts.
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Out of breath, you stumble through the doors of the Emergency Room at the Thomas Jefferson
Hospital in Philadelphia. Head pounding, muscles aching, you scan the lobby for a doctor between deep,
uncontrollable coughs. Alarmed, the receptionist calls a nurse and through your narrow window of
consciousness you make out a flood of hospital personnel on their way to you, wearing yellow masks
covering their mouths, latex gloves and full-body protective gowns. As someone grabs your elbow, you
think you hear someone say, “Quarantine.” You’re hurried into a small, windowless room, the walls
covered by thick see-through plastic hanging from the ceiling. You lay down in the sterile bed wrapped
with paper and the world starts to fall away, as a river of doctors, nurses and scientists pour into your
room, passing charts, needles, and supplies to one another. Someone throws a cooling blanket on you.
“For the fever,” the muffled voice says through a mask.
And then come the tests. Blood is drawn; urine’s collected; and chest X-rays are taken. A doctor
reads your name from the license he pulled from your wallet. Half-conscious, you listen to him as he
discusses what’s wrong with you. Given the symptoms, the clinical diagnosis is pneumonia, he says. But
the laboratory tests haven’t identified a causative agent. “How old are?” he asks. “49,” you respond. “Do
you smoke?” “Yes.” “Exercise?” “No.” Have you traveled abroad recently?” “No.” “Any friends or family
visited you from out of the country?” Again, “No.” “What about foods…” “Have you tried any unusual or
exotic foods lately?” You shake your head, no. “Why don’t you tell me everywhere you’ve been in the
last 14 days,” he continues.
You say you’re a journalist for a local newspaper in Philadelphia and that you’ve been at work all
week. Nothing unusual or out of the ordinary, you confess. “And the week before that?” the doctor asks,
still writing notes in his chart. You think for a moment, looking up to the ceiling. “Oh yeah; actually, I
covered the American Legion Convention in Philadelphia last week.” “At the Bellevue-Stratford Hotel?”
the doctor asks, concerned. “Yeah, how did you –“. He turns to the nurse and says, “We’ve got another
case of Legionaries. Let’s get those guys from the CDC in here. I think we’ve got an outbreak on our
hands.”
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It’s July 21st, 1976 and we’re at the Bellevue-Stratford Hotel in Philadelphia, a 19-story goliath
built in the early 1900s, right in the city’s center. It’s the first day of the 58th annual state convention of
the American Legion, the veteran’s organization which hosts commemorative events, volunteer
activities and political meetings. Over 4,000 people are in attendance and–talking amongst themselves–
convention-goers are sharing stories, shaking hands over introductions, and preparing for the keynote
address which will kick of the 4-day meeting. What the few thousand American Legion members don’t
know is that tiny droplets of water, called aerosols, are floating in the air. And they are carrying a
potentially fatal bacterium named after the very convention they’re attending. And with every
inhalation, the bacteria flows into their noses and mouths, finding home deep within their lungs, as they
contract what is known today as Legionnaire’s Disease.
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Welcome everyone, my name is Dustin Grinnell and I’m the writer here at Charles River Labs,
and you’re listening to the first podcast in what we’re calling EurekaLab, inspired by the NPR radio show,
RadioLab. Through these feature-styled podcasts, we’ll explore thought-provoking topics and tell
intriguing stories and scientific adventures, and misadventures. In the spirit of the 1994 best-selling
book, The Hot Zone, and recent film Contagion, both chilling accounts of virus outbreaks, we thought
we’d kick off our first story in the podcast series with the infamous outbreak of Legionnaire’s Disease in
1976 at the Bellevue-Stratford Hotel in Philadelphia.
But let’s start first with the idea of an outbreak. What is an outbreak? And better yet, who’s on the
front lines protecting us from them? To answer these questions we’ve got to travel to the Center for
Disease Control and Prevention, better known by its acronym–the CDC, a Washington, DC-based
government organization established to protect the public’s health through the prevention of disease
and health threats. Health threats…like outbreaks.
According to the CDC, an outbreak is: “the occurrence of more cases of disease than normally
expected within a specific place or group over a given period of time.” Which basically means: A lot of
people get sick, in a relatively short period of time, and usually no one knows why. But there are
scientists who concern themselves with that why. Many of them were popularized in movies like
Outbreak and Contagion, as well as in the book The Hot Zone by Richard Preston, the story of an Ebola
Virus outbreak in the 80’s. Such scientists are called epidemiologists and they study how often and in
what quantity disease occurs in large populations. In the event of an outbreak or epidemic, outbreak
investigation specialists, a branch of epidemiology, look for the source of an infectious disease as well as
try and prevent it from spreading. These are the CDC’s disease detectives, the scientific sleuths
responsible for finding and eradicating threats against our health and putting a lid on any and all
outbreaks which have spread. “The real stories of CDC’s disease detectives are just as exciting as
anything you’ll see in a theater,” says the CDC’s website in reference to the movie Contagion. According
to the government organization, in the last two years, they’ve sent doctors and scientists to 750 health
threats and in the last decade have blocked potential killers, such as SARS, as well as created a vaccine
for H1N1.
But the disease detectives sent to Pennsylvania in 1976 didn’t have an answer for the Legionaries
outbreak. In fact, it took almost a year after the initial outbreak at the American Legion convention
before the disease’s causative agent was identified. In that time, 221 people contracted Legionnaires
and fell ill. 34 lost their lives.
But what did someone feel like after they left the Bellevue-Stratford Hotel that July? What does
Legionnaires do to the human body? What would you experience if infected; what symptoms would you
exhibit? And finally, what were the disease detectives at the CDC doing to help those infected?
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It’s almost the end of July, and five days have passed since the convention. You’re home now,
sitting at the dinner table in your house, a small cape, tucked away at the end of a quiet road in a
suburban neighborhood just outside of Philadelphia. On the table are foods of the summer: freshlygrilled hamburgers, corn on the cob and potato salad. You usually love potato salad. But not tonight;
tonight you’re not very hungry. You feel, well, off. You raise a hand to your forehead, wiping some sweat
away, and set down your fork, your plate still full with food. “I think I’m gonna to go to bed early,” you
say to your wife and son. With your clothes and shoes still on, you collapse face-first into your bed,
falling asleep immediately.
Legionnaire’s disease, named after the “Legionnaire’s” who attended the American Legion
convention in Philadelphia in 1976, is a type of pneumonia, or infection of the lungs. It’s caused by
Legionella, which includes several strains of gram-negative bacteria that can cause Legionellosis,
characterized by respiratory illness, high fever and pneumonia. Ninety percent of the time, Legionellosis
is caused by a bacterium called Legionella pneumophilia. It is this strain of bacteria which has found its
way deep within your lungs, thriving off the moist, warm environment.
As it turns out, there are three conditions Legionella bacteria require in order to thrive: Heat, the
optimal temperature being 95 degrees Fahrenheit, stasis, or lack of movement, and aerosolization, that
is, dispersal in the air. While the bacteria are found in natural freshwater environments, they aren’t
typically present in sufficient enough numbers to cause disease. According to the CDC, Legionella are
quite at home in drinking water systems, cooling towers, and whirlpool spas like hot tubs.
Unsurprisingly, most outbreaks originate in such areas.
Those most vulnerable to the bacteria include middle-aged and older people, smokers, those in poor
physical condition, and individuals with weakened immune systems. The bacteria enter the body by
inhalation of airborne water droplets, or by drinking water harboring the bacteria. Symptoms of
Legionaries usually begin 2 to 14 days after exposure. By the time the American Legion convention ends,
you and thousands of other attendees have inhaled millions of particles of Legionella floating in the air.
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You wake up, open your eyes, and scan your bedroom. Your blankets are strewn across the bed and
soaked with sweat. Right away, you remember the night of tossing and turning as well as the dramatic
swings between teeth-chattering chills and extreme heat. Your head’s pounding, your muscles ache…
actually–everything aches. And you’re having trouble breathing. Between every two or three breaths,
there is one where you feel short of air and breathless for a moment. “Hunny, you look terrible,” your
wife says, as she rolls over to face you. You feel terrible. You lumbar out of bed, walk into the bathroom
and–squinting from the lights–look in the mirror. A zombie looks back. You begin coughing, two weak
coughs at first, then more, increasing in intensity. Between coughs, you rummage through the medicine
cabinet, looking for a thermometer. Finding it, you place it under your tongue, eager for answers.
Your 6-year-old son runs into the room like a freight train, ready for his daily wake-the-parents
game. He jumps up on the bed, bouncing up and down. “Tell me a story, daddy,” he yells while you
press the sides of your cheeks in the mirror, still trying to figure out why you feel the way you do. You
wife pulls the thermometer from your mouth. “107 degrees?” she says, skeptical. That can’t be right,
you think. You start coughing again–this time a string of deep, chest-rattling coughs. You double over,
covering your face with your arm, holding onto the sink for balance. Then you see a see the stain on the
inside of your elbow–a dark-red blotch. It’s blood. Still bent over, trying to hold yourself upright, you
turn to son tumbling across the bed and manage to respond to his request, “No stories today, buddy.”
“But why not, daddy?” This time your wife answers, “Because your daddy’s going to the hospital.”
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Legionnaire’s Disease takes two distinct forms. Why it does is not known. The milder form, known
as Pontiac Fever causes a headache, muscle aches and a fairly severe fever. The symptoms, which
usually last around 2 to 5 days, don’t require medical intervention and typically go away on their own.
Complete recovery time: one week. But the disease can also manifest in another, more dangerous form,
known as legion fever. This severe form of the infection causes pneumonia, as well as chest pain,
coughing, difficulty breathing and high fever. Along with pneumonia-related symptoms, those with
Legion Fever often experience fatigue, loss of appetite, diarrhea, vomiting and loss of coordination. And
unlike Pontiac Fever, which requires no treatment and clears up in under a week, legion fever lasts much
longer and requires medical treatment, usually antibiotics.
Around this time in the late 1970’s, a great fear for epidemics was growing in the American public.
Michael Crichton’s book, the Andromeda Strain, which popularized a virus outbreak, was a best-seller.
Government officials were particularly frightened by a new strain of influenza known as Swing Flu. Many
thought an epidemic was imminent and the Presidential administration announced plans for wide
spread vaccination of the disease. So when news organizations picked up Legionaries, a mysterious
infectious agent which had no known drug or therapy, fear of an outbreak and potential epidemic
spread. And the pubic began to panic. The disease had already casted a dark cloud over those who had
attended the July convention. One woman, recalling her experience as one of the infected, said she
visited a local store and the cashier, fearful that she was contagious, wouldn’t even touch the money
she handed him.
A week into the outbreak, a newspaper headline read, “Six Days, 25 deaths and Still No Answer.”
But the CDC was searching for answers. In fact, the 20 epidemiologists who were sent to Pennsylvania to
investigate, the most sent to an outbreak in the agency’s recorded history, were pouring over records of
admitted patients, calling hospitals to identify new cases and conducting interviews with the infected.
But the investigation was hampered by the fact that the American Legion didn’t have a registration list,
so those who attended couldn’t be tracked down and contacted. Communication between federal, state
and local health investigators was also poor and many doctors at the time complained they weren’t
receiving proper feedback or advice from health officials. It was later reported that a similar outbreak
had happened once before at the Bellevue-Stratford, where 19 cases of a disease similar to Legionaries
broke out. Such knowledge could have prevented the outbreak or at least facilitated the investigation.
With all of this in the background, news coverage was spreading and many speculated that an epidemic
of swing flu had begun. Pennsylvanian’s avoided the city of Philadelphia altogether and many began to
panic.
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Such panic found its way into the hospitals as well–where we started the story. Your fever’s
worsened since you were admitted four days ago and you fear the coughs, which rock you into the fetal
position when they come, will never let up. And the pain killers the doctors gave you seem to be no
match for the body pains and splitting headaches, which you wish away every minute of the day.
But the doctors are trying to help and your door has been a highway for medical professionals.
They’ve tested your urine’s response to many known antigens, as well as collected and tested samples
of phlegm from your lungs. On top of testing for toxins and poisonous gases, they’ve analyzed your
blood for the presence of 17 heavy metals. But even with the tests and the x-rays, the doctors and
epidemiologists from the CDC don’t know what’s actually causing your symptoms.
“Well it’s not influenza,” your doctor says, slapping the x-ray picture of your chest onto the viewing
box attached the wall, its back light shining brightly. But given your symptoms, he says, you’ve definitely
got pneumonia, an inflammatory condition of the lung. “As you can see here,” he says, pointing to a
rectangular blob of white space where supposedly only air should be, “this patch of light is causing your
symptoms.” “What is that?” you ask. He responds by saying it’s an infection. You ask the cause. “Well it
could be any number of infectious microorganisms: bacteria, viruses, fungi, even parasites.”
He proceeds to tell you that over a hundred people have already come into the hospital with your
symptoms. And they all originated from the American Legion Convention, which took place a week ago.
“We alerted the CDC after the 4th case,” he tells you. “After you came in we knew we were dealing with
an outbreak.” You ask if anyone has died and he goes silent. He then follows up with his obligatory,
“We’re doing everything in our power…” That’s a yes, you think.
“Its pneumonia,” he says. “We just don’t know the agent behind it.” But he tells you he’s put you on
ciprofloxacin, an antibiotic, and that the first patient who came in responded well to it and is recovering
now. He pats you on the leg with his latex-covered hand and gets up to leave. “But what if we can’t find
what’s causing this?” you ask. He turns at the doorway and says, “Don’t worry. The CDC’ll figure it out.
It’s what they do.”
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But it was until January of 1977, almost a year later, until they figured it out. It was Dr. Joseph
McDade, a laboratory scientist at the CDC, who solved the mystery after heading into the lab, “To put to
rest a hunch he had about something,” he later said. And, as it turns out, once we learned what caused
the outbreak at the American Legion convention it became apparent that Legionella wasn’t actually an
unknown agent. The disease was linked to earlier outbreaks, one of which caused 15 deaths in a
Washington hospital in 1965.
While 34 people tragically lost their lives during the Philadelphia outbreak, most infected at the
convention did recover, including our fictitious journalist who received antibiotics early during the
infection. And because the Legionella bacteria are not spread from person-to-person, the medical
professionals who treated him were not infected during the outbreak.
Since 1976, the mortality rate for Legionnaires Disease has dropped considerably and with early
diagnosis and proper treatment, the statistics are between 5 and 30%. But while Legionnaires disease
has since been demystified, according to the Bureau of Communicable Disease Control, between 8,000
and 18,000 people are hospitalized with the disease in US every year. The largest outbreak ever
recorded happened in July of 2001 in Spain. Of the 449 confirmed cases, only 1% percent died from the
infection.
And many lessons were learned from the first outbreak. It actually improved how we reacted and
fought diseases such as SARS and avian flu. Lessons were also applied to the anthrax release after
September 11th. Dr. Victor L. Yu, a Legionnaires researcher, together with the Allegheny County Health
Department, published a practical guide to decrease the chances of Legionnaires’ disease transmission,
recommending frequents checks of hot water tanks, faucets and shower heads that serve hospital
patients vulnerable to Legionnaires. Updated annually, the guidelines also include procedures for
disinfecting water systems via adding chemicals like chorine, or raising the water’s temperature.
Today, if you walk into the hospital with pneumonia or flu-like symptoms, you’ll likely be tested for
Legionaries. And although legionella bacteria can show up in most water systems, it’s very unlikely to
show up in private homes. Such was the premise for a study by Dr. Yu and researchers at the VA medical
center in Oakland. Results showed that only 7% of the residencies had the bacteria in their water
samples and no person had the disease. “What did we find?” Dr. Victor L. Yu said after the study. “That
they weren't at risk," he said. "And that was a relief for everybody."
Acknowledgements
Thank you for listening to this addition of EurekaLab. This podcast was supported by Charles
River Lab’s and the Director of Public Relations Amy Cianciaruso. It was written and narrated by Dustin
Grinnell. Audio production was performed by Alex Hardy.