What was the Milwaukee diarrhea outbreak of 1993?
List of authors. Early in the spring of 1993 there was a widespread outbreak of acute watery diarrhea among the residents of Milwaukee.
What happened at the Howard Avenue water purification plant in Milwaukee?
It is suspected that The Howard Avenue Water Purification Plant, one of two water treatment plants in Milwaukee at the time, was contaminated. It is believed that the contamination was due to an ineffective filtration process. Approximately 403,000 residents were affected resulting in illness and hospitalization.
How many people were affected by the Milwaukee water crisis?
Over the span of approximately two weeks, 403,000 of an estimated 1.61 million residents in the Milwaukee area (of which 880,000 were served by the malfunctioning treatment plant) became ill with the stomach cramps, fever, diarrhea and dehydration caused by the pathogen.
How did the Milwaukee virus get into Lake Michigan?
The source of the oocysts leading to the outbreak in Milwaukee and the timing of their entrance into Lake Michigan remain speculative. Possible sources include cattle along two rivers that flow into the Milwaukee harbor, slaughterhouses, and human sewage.
What caused the 1993 Milwaukee cryptosporidiosis outbreak?
MacKenzie et al. and the CDC showed that this outbreak was caused by Cryptosporidium oocysts that passed through the filtration system of one of the city's water-treatment plants, arising from a sewage treatment plant's outlet 2 miles upstream in Lake Michigan.
When was the Cryptosporidium outbreak in Milwaukee?
The 1993 Milwaukee cryptosporidiosis outbreak remains the largest epidemic of waterborne disease in U.S. history.
How many people died of Cryptosporidium in Milwaukee?
Milwaukee experienced the largest outbreak of cryptosporidium in the spring of 1993. The outbreak made 400,000 sick. Over 4,000 were hospitalized. And 104 deaths were recorded.
What is the cause of Cryptosporidium?
It is caused by microscopic germs—parasites called Cryptosporidium. Cryptosporidium, or “Crypto” for short, can be found in water, food, soil or on surfaces or dirty hands that have been contaminated with the feces of humans or animals infected with the parasite.
What happened in Milwaukee disease outbreak?
This massive outbreak of watery diarrhea was caused by cryptosporidium oocysts that passed through the filtration system of one of the city's water-treatment plants. Water-quality standards and the testing of patients for cryptosporidium were not adequate to detect this outbreak.
What is Cryptosporidium in water?
Cryptosporidium parasites get into surface water sources, such as rivers and lakes, from the stool (feces) of infected animals or people. Public water systems that get their water from these surface water sources can contain Cryptosporidium oocysts (the egg-like form of the parasite).
How many people died from the 1993 Cryptosporidium outbreak in Milwaukee quizlet?
The 1993 Cryptosporidiosis outbreak (a protozoan) was the largest waterborne disease outbreak in US history. Over 100 people died.
Where does Milwaukee get its drinking water?
Lake MichiganWhere Does Milwaukee Source Its Drinking Water? Milwaukee sources its drinking water from Lake Michigan. Lake Michigan has had a long history of pollution, including a recent lawsuit involving Chromium 6 releases from an abutting steel facility.
How many people died in the Milwaukee outbreak?
sixty-nine peopleIn the spring of 1993, approximately 400,000 people fell victim to what Milwaukeeans have since referred to as “Crypto.” At least sixty-nine people—mostly people suffering from AIDS—died in this Cryptosporidium outbreak, which would become the country's largest waterborne disease epidemic on record.
What bugs can cats pass to humans?
Certain feline intestinal parasites, including roundworms (Toxocara) and hookworms (Ancylostoma), can also cause disease in people. Children are particularly at risk due to their higher likelihood of contact with soil that has been contaminated by cat feces.
What is dog Crypto?
Cryptosporidium in dogs is a water-borne protozoan parasite that most commonly affects dogs who play in bodies of fresh water, and it can cause severe diarrhea among other symptoms. An infection with cryptosporidium is called cryptosporidiosis.
Can humans get Cryptosporidium?
Cryptosporidium can infect humans, cattle and other animals, particularly farm animals. There are two main species of cryptosporidium that cause infection in humans - Cryptosporidium hominis (C. hominis) and Cryptosporidium parvum (C. parvum).
What was the 1993 outbreak in Milwaukee?
The 1993 Milwaukee Cryptosporidiosis outbreak was a significant distribution of the Cryptosporidium protozoan in Milwaukee, Wisconsin, and the largest waterborne disease outbreak in documented United States history. It is suspected that The Howard Avenue Water Purification Plant, only one of two water treatment plants in Milwaukee, was contaminated.
How much did the Milwaukee outbreak cost?
The total cost of the outbreak, in productivity loss and medical expenses, was $96 million dollars. The city of Milwaukee has spent upwards to $510 million in repairs, upgrades, and outreach to citizens.
When did Milwaukee get GI?
On April 5, 1993, Milwaukee Health Department received increased reports of gastrointestinal (GI) illness at their local hospitals and calls of complaints related to reduced water-quality aesthetic.
Did hospitals screen for cryptosporidium?
The only findings were that turbidity was slightly increased but still below federally recommended levels. At the same time, hospitals did not routinely screen for cryptosporidium, but because patients were all experiencing similar symptoms, hospitals were asked to test for cryptosporidium.
When did Milwaukee water get rid of Cryptosporidium?
Courtesy of Milwaukee Water Works</figcaption></figure> </div> <p>Since the Cryptosporidium outbreak of 1993, Milwaukee has made numerous improvements to its drinking water treatment.
How many contaminants are in Wisconsin water?
Lee Boushon, chief of the Wisconsin Department of Natural Resources’ public water supply section, said the vast majority of water systems focus only on a standard list of 91 contaminants regulated by the U.S. Environmental Protection Agency.
How far off Lake Michigan is Milwaukee water intake?
An $11 million project extended the Howard Avenue water intake 4,200 feet to a distance of two miles off Lake Michigan’s shoreline, beyond the path of contamination from the city’s industrial harbor.
How many people died from parasites in Milwaukee?
Two decades since a parasite in Milwaukee drinking water killed 69 people and sickened 400,000, the city has become a national leader in testing for unregulated contaminants. Kate Golden/Wisconsin Center for Investigative Journalism Credit: Kate Golden / Wisconsin Center for Investigative Journalism
What chemicals does Milwaukee Water Works test for?
The 2011 report shows trace amounts of a few emerging contaminants, including DEET, the mosquito repellent; sulfamethoxazole, an antibiotic; and perfluorooctane sulfonate, a persistent, man-made industrial chemical.
Who is the executive director of Milwaukee's sewerage district?
Kevin Shafer, executive director of Milwaukee’s sewerage district, agreed that filtering out bad stuff from the water supply is important. But even better, he said, is to keep it out of the water system in the first place.
Who is the superintendent of Milwaukee Water Works?
Carrie Lewis , superintendent of Milwaukee Water Works, said the city tests its drinking water “for everything within reason” and releases the results to the public. Courtesy of Milwaukee Water Works.
When did Wisconsin get contacted by Milwaukee?
On April 5, 1993 , the Wisconsin Division of Health was contacted by the Milwaukee Department of Health after reports of numerous cases of gastrointestinal illness that had resulted in widespread absenteeism among hospital employees, students, and schoolteachers.
How did the MWW plant treat water?
At the time of the outbreak, both MWW plants treated water by adding chlorine and polyaluminum chloride (a coagulant to enhance the formation of larger particulates), rapid mixing, mechanical flocculation (which promotes the aggregation of particulates to form floc), sedimentation, and rapid sand filtration.
How many stools were tested for Salmonella in 1993?
During the period from March 1 through April 16, 1993, a total of 2300 stool specimens were submitted to the 14 clinical laboratories in the Milwaukee vicinity for routine culture for bacterial enteric pathogens. Twenty specimens (0.9 percent) were positive for salmonella, 10 (0.4 percent) for shigella, and 11 (0.5 percent) for campylobacter; 1 of 80 specimens (1.3 percent) cultured for yersinia and 1 of 73 (1.4 percent) cultured for aeromonas were positive. During the same period, 14 of 1744 stool specimens examined for ova and parasites (0.8 percent) were found to have giardia, and 5 of 266 specimens cultured for enteric viruses (2 percent) were positive. An enzyme immunoassay kit for rotavirus was used to test 96 specimens, 3 of which (3 percent) were positive. From March 1 through April 6, 12 of 42 stool specimens (29 percent) tested for cryptosporidium were positive; from April 8 through April 16, 331 of 1009 specimens (33 percent) were positive. We found no evidence of cyclospora infection. Oocysts examined by the Centers for Disease Control and Prevention were 4 to 6 micrometers in diameter and were positive for cryptosporidium with monoclonal-antibody staining.
How long did diarrhea last in 1993?
Among these 436 people, the median duration of diarrhea was 3 days (range, 1 to 45).
When did watery diarrhea start?
Reported Date of the Onset of Watery Diarrhea during the Period from March 1 through April 28, 1993, in 436 Cases of Infection Identified by a Random-Digit Telephone Survey of the Greater Milwaukee Area.
When was the MWW survey conducted?
To determine representative clinical characteristics of illness among the people affected by the outbreak, a telephone survey was conducted on April 9, 10, and 12 with the use of randomly selected telephone numbers from the MWW service area.
When did the southern plant start using alum chloride?
Although marked improvement in the turbidity of treated water had been achieved by April 1 with the use of polyaluminum chloride, on April 2 the southern plant began to use alum instead of polyaluminum chloride as a coagulant. On April 5, the turbidity of treated water increased to 1.5 NTU.
How does Milwaukee water work?
The Milwaukee Water Works treats Lake Michigan water at the Linnwood Water Treatment Plant on the north side and the Howard Avenue Water Treatment Plant on the south side. The Linnwood intake is 1.25 miles from the shore at a depth of 60 feet. The Texas Avenue intake supplying the Howard Avenue Water Treatment Plant is 2.5 miles from shore, also at a depth of 60 feet. The lake water passes through a multiple barrier treatment process barriers to protect public health. The barriers destroy and remove illness-causing microorganisms in the lake water.#N#The primary form of disinfection is ozone gas. Ozone generators spark liquid oxygen, O 2, with electricity to create ozone gas, O 3 . In the first stage of water treatment, ozone is bubbled into the water in large contactor tanks. Ozone attacks illness-causing micro-organisms and breaks apart harmful compounds at the atomic level. With its three oxygen atoms, ozone is unstable and highly reactive. It readily gives up one atom to the carbon in the membranes of microbes. Ozone destroys illness-causing microorganisms such as Cryptosporidium and Giardia. Ozone breaks apart compounds that can cause taste and odor. Using ozone as a disinfectant reduces the formation of disinfection byproducts.#N#Particles in the water are then removed through coagulation, flocculation, settling, and biologically active filtration.Chlorine is added as a secondary disinfectant. Fluoride is added to reduce dental cavities. A phosphorous compound is added to control pipe corrosion to prevent lead that may be present in pipes from leaching into the water. Finally, chloramine disinfection maintains a residual in the distribution system to protect against bacterial contamination. The Wisconsin Department of Natural Resources (DNR) requires water utilities to maintain a detectable level of disinfectant throughout the distribution system to maintain bacteriological protection.
What is the primary form of disinfection in lake water?
The barriers destroy and remove illness-causing microorganisms in the lake water. The primary form of disinfection is ozone gas . Ozone generators spark liquid oxygen, O 2, with electricity to create ozone gas, O 3 . In the first stage of water treatment, ozone is bubbled into the water in large contactor tanks.
How does ozone help with disinfection?
Ozone breaks apart compounds that can cause taste and odor. Using ozone as a disinfectant reduces the formation of disinfection byproducts.
What is the first stage of water treatment?
In the first stage of water treatment, ozone is bubbled into the water in large contactor tanks. Ozone attacks illness-causing micro-organisms and breaks apart harmful compounds at the atomic level. With its three oxygen atoms, ozone is unstable and highly reactive.
How long does it take for water to move from Linnwood to Lake Michigan?
It takes approximately 22 hours for water to move from Lake Michigan through the entire Linnwood Water Treatment Plant. The time it takes for the water to move from the treatment plant to your home depends on how far you live from the plant and overall system demand at any given time.
What is Wisconsin DNR?
The Wisconsin Department of Natural Resources (DNR) requires water utilities to maintain a detectable level of disinfectant throughout the distribution system to maintain bacteriological protection. All chemicals that are added are certified food grade, safe for human consumption.
Why is ozone used as a disinfectant?
Using ozone as a disinfectant reduces the formation of disinfection byproducts. Particles in the water are then removed through coagulation, flocculation, settling, and biologically active filtration.Chlorine is added as a secondary disinfectant. Fluoride is added to reduce dental cavities.
