EPA claims Crytosporidium is a Primary Pathogen in sludge Biosolids that only causes Gastroenteritis
24. Crytosporidium----------------------------------- Gastroenteritis
Cryptosporidium parvum is a coccidian protozoan parasite accepted as a pathogen of the digestive tract in humans.
The infection is associated with diarrhea (1–6), and it is more prevalent in children who are malnourished (1, 5, 7,
8). In immunocompromised hosts, the impact of the disease is severe and includes respiratory problems, cholecystitis,
hepatitis, and pancreatitis. On the other hand, in immunocompetent persons, infection is considered to be a selflimited
disease, and the subclinical infection rate is unknown (3, 9, 10).
At least 8 species of Cryptosporidium are described as infecting humans. C. hominis and C. parvum are the most
frequently observed in intestinal infections in humans (3). C. meleagridis is also detected both in immunocompetent and
immunodeficient patients, although at a lower rate than C. parvum (4).
Respiratory tract infection by Cryptosporidium spp. has been described for immunodeficient persons, most all of whom
were coinfected with HIV. However, pulmonary cryptosporidiosis was also described in patients without HIV infection (5,
There is no antibiotic or drug treatment that will cure cryptosporidium. Most people with a healthy immune
system will recover on their own. Severe illness should be managed under the care of a physician.
Since the first reports of human cases in 1976, Cryptosporidium has been found worldwide. Outbreaks of
cryptosporidiosis have been reported in several countries, the most remarkable being a waterborne outbreak in
Milwaukee (Wisconsin) in 1993, that affected more than 400,000 people. According to Dr. Ian Gilson, "One-hundred-
and-three people with HIV and AIDS eventually died because of the contamination." Fifteen years later, “The cause is
not known and may never be known. There does not seem to be any obvious explanation.” "Carrie Lewis is
superintendent of Milwaukee Water Works. The utility draws in water from Lake Michigan and then treats it before
sending it to customers. A prevailing theory on what happened 15 years ago is that sewage overflows contaminated the
lake water. But Lewis doesn’t buy it. She says if human sewage was the source, people would have had to have been
infected with the parasite beforehand to excrete it, and there’s no evidence of that. There’s also speculation that cow
manure from upstate washed into the rivers that empty into the lake." “We have tested the watershed for 15 years
looking for cryptosporidium and we hardly ever find it in the rivers. So it does not seem that the environment was a huge
reservoir of it, so honestly, no clue,” Lewis says." REALLY?
"CDC's Emerging Infectious Diseases/Volume 3 Number 4/October-December 1997, reported that some samples that
were taken from infected people during the 1993 Milwaukee outbreak showed a human type of crytosporidium.
CDC has identified 2 strains of crytosporidium, one animal and one human. According to the report: The genotypic and
infection data from the four isolates we examined suggest a human rather than bovine source...
Furthermore, of the isolates tested in experimental infection studies, none could successfully infect laboratory animals.
These results lead us to suggest the possibility of a second transmission cycle that is anthroponotic and maintained
through person-to-person contact or through human sewage contamination of the water supply." (pp.7-8)
Many species of Cryptosporidium exist that infect humans and a wide range of animals. Although Cryptosporidium
parvum and Cryptosporidium hominis (formerly known as C. parvum anthroponotic genotype or genotype 1) are the
most prevalent species causing disease in humans, infections by C. felis, C. meleagridis, C. canis, and C. muris have
also been reported.
Infection with Cryptosporidium sp. results in a wide range of manifestations, from asymptomatic infections to severe, life-
threatening illness; incubation period is an average of 7 days (but can range from 2 to 10 days). Watery diarrhea is the
most frequent symptom, and can be accompanied by dehydration, weight loss, abdominal pain, fever, nausea and
vomiting. In immunocompetent persons, symptoms are usually short lived (1 to 2 weeks); they can be chronic and more
severe in immunocompromised patients, especially those with CD4 counts <200/µl. While the small intestine is the site
most commonly affected, symptomatic Cryptosporidium infections have also been found in other organs including other
digestive tract organs, the lungs, and possibly conjunctiva.
the usual safety measures for handling potentially infectious material should be adopted.
Some people with crypto will have no symptoms at all. While the small intestine is the site most commonly affected ,
Cryptosporidium infections could possibly affect other areas of the digestive or the respiratory tract .
Cryptosporidium can survive for days in swimming pools with adequate chlorine levels.
Do not rely on chemicals to disinfect water and kill Cryptosporidium. Because it has a thick outer shell, this particular
parasite is highly resistant to disinfectants such as chlorine and iodine
Contaminated water includes water that has not been boiled or filtered. Several community-wide outbreaks of
cryptosporidiosis have been linked to drinking municipal water or recreational water contaminated with Cryptosporidium.
Baby Calf Health: Common Diarrheal Diseases
Cryptosporidiosis - Transmission of cryptosporidia is by fecal-oral route. Within the intestines auto-infection can occur in
immuno-suppressed calves. The entire developmental cycle can occur within 72 hours. Natural infection occurs in
calves 1-3 weeks of age. Clinical signs include increased frequency of defecation, straining, anorexia, weight loss,
depression, and dehydration. Diarrhea is profuse, watery, and has a yellow color. Usually many calves are affected but
few die as a direct consequence of cryptosporidiosis. There appears to be a seasonal effect with more disease
occurring during fall/winter or stressful periods. Affected calves need supportive care since the disease is self-limiting
and the intestinal repair can be prolonged. Cryptosporidia oocysts are difficult to detect. Routine fecal tests will not find
the organism. A special acid-fast stain is required to diagnose cryptosporidiosis. Oocysts do not survive freezing or
temperatures above 150o F for 30 minutes, but will survive at 40o F in liquid slurries. Bleach nor alcohol are effective at
killing the oocysts. Strong Lysol (5% solution available from hardware stores) can be used to disinfect contaminated
surfaces. Cryptosporidiosis is a public health hazard! In humans, clinical signs include abdominal cramps, vomiting,
diarrhea, and fever (flu-like symptoms).