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.

Geographic Distribution:
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.

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.