Milwaukee Cryptosporidium outbreak
Encyclopedia
The 1993 Milwaukee Cryptosporidium outbreak was a significant distribution of the Cryptosporidium
protozoan in Milwaukee, Wisconsin
, and the largest waterborne disease outbreak in documented United States
history. The Howard Avenue Water Purification Plant (see Town of Lake water tower) was contaminated, and treated water showed turbidity
levels well above normal. It was one of two water treatment plant
s for Milwaukee. The root cause of epidemic was never officially identified; initially it was determined to be caused by the cattle genotype versus human genotype of the parasite as originally suggested. MacKenzie et al. showed that this outbreak was caused by cryptosporidium oocysts that passed through the filtration system of one of the city's water-treatment plants.
This abnormal condition at the plant lasted from March 23 through April 8, after which, the plant was shut down. 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. At least 104 deaths have been attributed to this outbreak, mostly among the elderly and immunocompromised
people, such as AIDS
patients.
Cryptosporidium
Cryptosporidium is a protozoan that can cause gastro-intestinal illness with diarrhea in humans.Cryptosporidium is the organism most commonly isolated in HIV positive patients presenting with diarrhea...
protozoan in Milwaukee, Wisconsin
Milwaukee, Wisconsin
Milwaukee is the largest city in the U.S. state of Wisconsin, the 28th most populous city in the United States and 39th most populous region in the United States. It is the county seat of Milwaukee County and is located on the southwestern shore of Lake Michigan. According to 2010 census data, the...
, and the largest waterborne disease outbreak in documented United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
history. The Howard Avenue Water Purification Plant (see Town of Lake water tower) was contaminated, and treated water showed turbidity
Turbidity
Turbidity is the cloudiness or haziness of a fluid caused by individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality....
levels well above normal. It was one of two water treatment plant
Water purification
Water purification is the process of removing undesirable chemicals, materials, and biological contaminants from contaminated water. The goal is to produce water fit for a specific purpose...
s for Milwaukee. The root cause of epidemic was never officially identified; initially it was determined to be caused by the cattle genotype versus human genotype of the parasite as originally suggested. MacKenzie et al. showed that this outbreak was caused by cryptosporidium oocysts that passed through the filtration system of one of the city's water-treatment plants.
This abnormal condition at the plant lasted from March 23 through April 8, after which, the plant was shut down. Over the span of approximately two weeks, 403,000 of an estimated 1.61 million residents in the Milwaukee area
Milwaukee metropolitan area
The Milwaukee–Racine–Waukesha metropolitan area is an urban area identified by the U.S. Census Bureau containing five counties in southeastern Wisconsin: Milwaukee, Waukesha, Racine, Washington and Ozaukee...
(of which 880,000 were served by the malfunctioning treatment plant) became ill with the stomach cramps, fever
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
, diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
and dehydration
Dehydration
In physiology and medicine, dehydration is defined as the excessive loss of body fluid. It is literally the removal of water from an object; however, in physiological terms, it entails a deficiency of fluid within an organism...
caused by the pathogen. At least 104 deaths have been attributed to this outbreak, mostly among the elderly and immunocompromised
Immunosuppression
Immunosuppression involves an act that reduces the activation or efficacy of the immune system. Some portions of the immune system itself have immuno-suppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment of other...
people, such as AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...
patients.
External links
- Cryptosporidium and public health (Drinking Water and Health Newsletter)
- Cost of Illness in the 1993 Waterborne Cryptosporidium Outbreak, Milwaukee, Wisconsin (CDC)
- Cryptosporidium: A Risk to Our Drinking Water (Wisconsin DNR)
- A Massive Outbreak in Milwaukee of Cryptosporidium Infection Transmitted through the Public Water Supply (New England Journal of Medicine)