Forensic Files - Season 2, Episode 13 - Deadly Parasites - (In HD) | Forensic Files

In the spring of 1993, an unexplained illness struck the residents of Milwaukee, Wisconsin.
400,000 people developed serious gastrointestinal illness. 4,000 were hospitalized and by
the time it was under control, more than 100 people died. Health officials suspected it was influenza,
but it was something more serious and much more difficult for medical detectives to uncover.
[Music] [Music] [Music] Milwaukee, Wisconsin, the 17th largest city in the United States with a
population of almost 1 million people. It's a city known for its German culture, summer festivals,
and long, cold winters with plenty of snow. Milwaukee is the home of several large
breweries producing 11 million barrels of beer annually. But in the spring of 1993,
Milwaukee became famous for something else. An unexplained outbreak of gastrointestinal
illness which spread rapidly throughout the community. 4,000 people rushed to area hospitals all with the same
symptoms. severe cramps, diarrhea, nausea, and fever. >> I've had the diarrhea off and on all
week. I missed two days of work, and I thought it was gone, and it came back again.
>> Hardest hit were individuals with weakened immune systems, infants, the elderly, cancer, and AIDS patients, and
those who had organ bone marrow transplants. Four-year-old Becky Ferman suffered from
a particularly bad case. She was just a vibrant child. She was highly intelligent, very vivaceious, very
talkative, very friendly. Um, just a normal kid. Becky Ferman was born HIV positive, which made her particularly
susceptible to the mysterious outbreak. >> This got to be absolute water turning
from brown to yellow to green. Terrible odor. and she would have 8 9 10 11 12 bow movements a day.
>> 40-year-old Antonio Clauddio was also affected. Like Becky, he too is HIV positive, but the severity of the cramps
and diarrhea he developed during the outbreak was alarming. >> Yeah, I freaked out.
I was like is is this what's happening to me a nature of course of the virus itself of the HIV
AIDS or is this something else >> the primary suspects were chagela giardia campalobacttor
or salmonella but stool samples from the infected individuals were all negative >> we knew this was big I I mean, we knew a
lot of people were sick. We knew a lot of kids were sick. We were beginning to get reports from hospitals that
patients, particularly with immune compromising conditions, particularly HIV AIDS, were having very difficult
times shaking loose of this outbreak. And so, we were uh beginning to understand that this was in fact an
epidemic. >> And health officials had no idea what was causing it. [Music] Within 24 hours of the outbreak, the
mayor of Milwaukee knew he faced a serious dilemma. No American city had ever faced this type of crisis before.
>> The concern in the health department was the beginning of, you know, a real concern. What is this? You know, how can
so many people get sick all at one time? >> If the outbreak was caused by a contaminated food source, stool samples
would contain the bacteria which caused it. And health officials could find no common food source that all of the sick
individuals used. Food illnesses usually center around a common food distribution
center, processing plant, restaurant, or grocery store. But one common element among all of the
infected individuals was water. Officials analyzed the water quality records at the city's municipal water
supply, but all of the water quality levels were within guidelines established by the Environmental
Protection Agency for safe drinking water. >> We went back and indicated that to the
health department and they continued on with their investigation into other areas. But when scientists looked at the
distribution pattern of the outbreak, they noticed that most of the cases were clustered in the south side of the city.
>> We believed we would have witnessed a more normal uniform distribution of illness had it been an airborne virus
because it would have started at a point and moved outward. Since the outbreak seemed to be centered in Milwaukee
southside, this narrowed the focus of the investigation. Becky Ferman lived on Milwaukee
Southside. Her doctors had no idea what caused her illness and soon discovered they couldn't cure it in individuals
like Becky who had HIV. One of the things was that she was limited in what she could do as far as
where we could go and what we could do with her as far as playing because she would have these accidents. Another
thing was a general weakness uh because of the constant diarrhea. >> Gastrointestinal illness is usually
caused by something that is ingested once again pointing to food or water. The water plant which supplied Milwaukee
Southside reported that the only unusual readout was a peak in turbidity one week
before the outbreak. Turbidity measures the amount of foreign particles in the water.
After a rainstorm or when snow melts, turbidity levels will temporarily rise. Storms churn river and creek bottoms,
and melting snow will often gather particles as it runs into streams. Health officials wondered if the
increase in turbidity levels was cause for concern. The municipal water supply was disinfected with chlorine. Was it
possible that the city's water supply was contaminated with something that didn't show up in water tests and that
chlorine would not kill? If so, the entire city would be at risk and one of the city's largest industries could also
be affected, the brewing industry. The breweries were among the largest users of municipal water. If there was
an unknown organism in the water, was it being shipped all across the country by
the tens of thousands of gallons a day? [Music] Health officials suspected that something in Milwaukeee's water supply
was causing the outbreak of thousands of cases of gastrointestinal illness. The water department insisted that the
water quality levels were all within standards set by the Environmental Protection Agency and that the water was
safe to drink. Hospitals and laboratories throughout Milwaukee continued to analyze stool samples from
the thousands of individuals affected. >> Everything pretty much was a dead end.
Everywhere we looked was everything was negative. Sandy Shraderis was doing some of those
tests at a local hospital. As a microbiologist, she was performing the routine tests on patients hospitalized
with the mysterious illness. The standard test was an iodine stain. When added to the stool samples, the iodine
would show if parasites were present. But all of the iodine tests were negative. On her own, Sandy Shraderus
decided to go one step further. She remembered something she learned earlier in her training that microbiologist
should be on the lookout for parasites which do not show up on standard tests. With that in mind, she noticed a number
of unusual structures in the samples. Structures which didn't react with the iodine stain. At that point, I don't
know exactly what it is yet, but it means something. That's your first clue. >> So, she performed an acid fast stain.
She flooded the stool sample with a red stain, then washed the sample with alcohol and sulfuric acid. During the
final step, an additional green stain is added under the microscope. She thought she saw a highly infectious,
potentially deadly parasite. >> First acidf stain wasn't real definitive. This is probably our first
line. It's easiest, it's quickest, it's done in about 10 minutes. And I didn't feel comfortable calling it on that. So,
we went on and did a fluorescent stain. >> The fluorescent stain introduces the parasites antibbody to the sample along
with a fluorescent agent. Under the microscope, Sandy Shraderus noticed a bright green glow. It was the
fluorescent agent attached to the antibbody. Proof that a parasite was present. It was cryptosperidium.
Little is known about cryptosperidium since it first infected humans just over 20 years ago. It's a one-sellled
organism, a protoonean parasite which is found in feces from young farm animals,
particularly calves. Cryptosperidium is an 80% of surface water, largely due to animal feces washed from farms into
nearby streams by heavy rains and melting snow. Here you can see the tiny cryptosperidia escaping from their
shells. Once they do, they multiply by the millions. When they spread throughout the gastrointestinal system,
they absorb nourishment, preventing the body from retaining fluids, and causing severe cramps, explosive diarrhea and
other flu-l like symptoms. A healthy individual with a healthy immune system can usually get rid of the parasite
within a week with no lasting effects. But it can be deadly for those with weakened immune systems like the
elderly, AIDS and cancer patients, and individuals with organ and bone marrow transplants. When lab technicians
retested other stool samples, they confirmed what Sandy Shraiderus first discovered. Cryptosporidium was found in
seven more stool samples. >> Once you knew what you're looking for, it was everywhere. I mean, we knew then.
Now we had the agent. Now, where was it coming from? That was the next step. >> Since cryptoperidium is a waterborn
parasite, it renewed fears that the city's water supply was contaminated. >> The mayor called an emergency meeting of
both city and state health officials. During that meeting, the mayor noticed one of the participants, Dr. Jeffrey
Davis, the state's epidemiologist, was drinking diet soda and not water. When the mayor turned to Dr. Davis and asked
if he would drink the city's water. Dr. Davis said no. >> It wasn't difficult once I asked Dr.
Davis if he'd drink the water. I mean, if he suspected, he's a scientist. He's an expert and and a very honest person.
Uh, you know, if he suspected that there could be problems with the water, that's
pretty good test right there. Since boiling was the only way to get rid of cryptosperidium,
the mayor immediately issued a boil water advisory recommending that all water be boiled for at least 5 minutes
before use. It was a bold recommendation with wide-ranging implications since tests for cryptoperidium in the city's
water supply had not yet been completed. Dental offices were closed since their drills were water cooled. Restaurants
were also affected since they use water for ice and washing dishes. Three days later, tests on Milwaukeee's water done
by an independent laboratory confirmed that cryptosperidium was present in the purified water from the Howard Avenue
water plant. The news of cryptosperidium contamination was especially terrifying
to one segment of the population, people with HIV infections or AIDS. >> For these patients, it was
life-threatening immediately. They knew what crypto was. This was not a new illness to them.
>> Cryptospidiosis for someone with a severely compromised immune system is a death sentence. Doug Nelson and the
organization he directs, the AIDS Resource Center of Wisconsin, went into crisis mode. He knew that individuals
with HIV AIDS would never get rid of the parasite, but his goal was to make sure
no one else became infected. The Howard Avenue water plant was immediately closed. The water flushed out and the
entire plant disinfected from top to bottom to remove any traces of cryptosperidium.
A few days after the boil water advisory, the number of cryptosperidiosis cases dropped
significantly, but the levels discovered in Milwaukeee's water supply had been potent.
One businessman traveling through Milwaukeee's airport reported getting sick after drinking just enough water to
swallow a few aspirin. Antonio Claudio was living in Houston when he tested positive for
cryptosperidiosis. He believes he was infected while visiting his mother who lived on the
south side of Milwaukee. Since there is no cure for cryptosporidiosis besides a healthy immune system, Antonio
lives each day with constant chronic diarrhea. >> Once you discover you have this this
disease, your life changes and there's just no way to get around it. Prayer helps a lot.
But um you just can't erase it. It's reality, no matter what portion of it, and just waiting to die.
Little Becky Ferman lost her fight with cryptosperidiosis. She died after battling its effects for
many months. Becky was in a coma, eyes closed, but she raised her hands to us and grabbed held with our hands, took
three breaths, and and a spirit and energy left. ripped the heart. Um, but a gratefulness because she wasn't in
pain anymore. She looked peaceful for the first time. Investigators soon had a theory for how
cryptosperidium contaminated Milwaukee's water supply. [Music] After an intensive investigation, health
officials developed a theory as to how cryptosperidium contaminated Milwaukeee's water supply. In early
April of 1993, heavy rains and the spring snow melt caused water runoff. The ground was
still frozen and unable to absorb the water. Manure from the farms and fields might have washed into nearby streams.
Manure which contained cryptosperidium. The cryptosperidia then made their way from the streams into Lake Michigan, the
source of Milwaukeee's drinking water in 1993. There were no filters or mass disinfectants used anywhere in the
United States which could eliminate the cryptosperidium in water plants. Chlorine was ineffective against it.
Over 400,000 people who ingested water from the Howard Avenue plant became ill. 4,000 were hospitalized.
104 died. That theory held for 4 years. During that time, the Centers for Disease Control in Atlanta, Georgia,
continued to investigate Milwaukeekey's cryptosperidium outbreak since it was the largest waterborne outbreak in
United States history. In 1997, scientists retested four stool samples from individuals infected during that
outbreak. They conducted DNA testing on the cryptos paridium. And when they did,
there was a shocking discovery. The type of cryptosperidium found in the four stool samples from the Milwaukee
outbreak did not come from farm animals. It was a new strain, one which came from
human waste. >> Our results suggest on the basis of the limited number of samples that we looked
at that the Milwaukee outbreak um was was not from pasture runoff but was from sewage contamination. When investigators
looked more closely at Milwaukeee's water supply, they found that the Howard Avenue water plant's intake was less
than 2 mi down current from a sewage treatment plant overflow valve in Lake Michigan. The CDC's discovery suggested
that human waste containing cryptosperidium was released from the sewage treatment plant traveled the 2 mi
downstream where it entered the water intake of the Howard Avenue water plant. Today, sewage from that plant is no
longer released into Lake Michigan. And the Howard Avenue water plant moved their intake further out into the lake
away from possible pollutants. And Milwaukee is building an ozenization facility. Ozone is a form of oxygen
which kills more microorganisms than chlorine. It's the only mass disinfectant process known to kill
cryptosperidium in water. When the facility is completed, Milwaukee will be the only major city in the United States
to ozenate its water. Every city around the country that relies on surface water
for its drinking water must study the Milwaukee example and must follow our lead in making those extraordinary
commitments to assure to their public that in fact the water that they consume is safe and that they will not get ill
from it and and that they will not die from it. >> I mean, I I felt terrible about that.
I'm not an expert on water, but I'm the mayor and uh you know, you kind of rely on your city to provide you with water.
It turns out that cryptosperidium has gotten in water supplies in other parts of the country. It's not that uncommon.
[Music] We went through a lot a lot of anger. not only anger at the loss of our daughter but the anger of loss of so
many friends. As time passed, we came to realize that yes, I we believe that public officials
were at fault for not knowing more about it, for not teaching us, but ultimately
we all are corporately responsible, you and I, and and the world for not caring about water until someone dies.
[Music] Why? [Music] Heat. Everybody. [Music]

Heavy rains and snow run-off carried manure into Milwaukee's water supply in 1993, leading to an epidemic of gastrointestinal illness affecting 400,000 people. Now in HD.

Brief Summary

The 1993 Milwaukee outbreak revealed cryptosporidium contamination in the water supply, affecting thousands and leading to significant health consequences.

Key points

Milwaukee's Mysterious Outbreak. In spring 1993, Milwaukee faced a severe gastrointestinal illness outbreak affecting 400,000 residents.
The Discovery of Cryptosporidium. Health officials confirmed the presence of cryptosporidium in Milwaukee's water supply, leading to a public health crisis.
A Tragic Loss. Little Becky Ferman lost her fight with cryptosporidiosis after battling its effects for months.
A Call for Change. Milwaukee's water supply contamination led to significant changes in water treatment practices across the country.

Episode highlights

Episode quotes

I missed two days of work, and I thought it was gone.

A resident describes their experience with the illness.

1:56WatchSep 26, 2025

Tension

75/ 100High tension

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