Cryptosporidiosis is a parasitic infection of the small intestine. Diarrhea is the main symptom, but in immunologically-impaired individuals, such as patients with HIV or AIDS, the symptoms can be severe or even fatal.
Cryptosporidiosis tends to be an acute short-term infection. It spreads through the fecal-oral route, often through contaminated water. It is also known as crypto.
In the United States (U.S.) there are an estimated 748,000 annual cases of cryptosporidiosis, but over 98 percent of cases go unreported.
Cryptosporidiosis causes gastric issues including watery diarrhea.
In people with a healthy immune system, the main symptom is self-limiting diarrhea.
Symptoms appear from 1 to 12 days after infection, with an average of 7 days. They last for up to 2 weeks or, in some cases, up to a month.
In a person with a healthy immune system, there may be:
no noticeable symptoms
persistent diarrhea that can last for a few weeks
Diarrhea is usually watery with mucus. Rarely, there may be blood or leukocytes in the diarrhea.
The person may also have stomach pains or cramps and a low fever.
Other symptoms include:
A carrier of cryptosporidiosis who does not show symptoms can still pass on the infection to others.
Even after symptoms have gone, an individual remains infective for some weeks.
The appearance of cryptosporidium in the gut.
Image credit: Alae-eddine GATI, 1987
The parasite is protected by an outer shell that allows it to survive outside the body for hours and makes it resistant to chlorine disinfection.
Infection happens through contaminated material such as earth, water, and uncooked or cross-contaminated food that has been in contact with the feces of an infected individual or animal.
Millions of crypto organisms, or oocysts, can be released in the bowel movement of an infected human or animal. Infection happens after accidentally ingesting the oocysts.
It is prevalent amongst those who are in regular contact with fresh water, including swimming pools.
A person can get crypto by putting anything in the mouth that has touched the feces of an infected person or animal. Some outbreaks have happened in day care centers, as a result of diaper changes.
It is not spread by contact with blood.
Cryptosporidiosis is responsible for 50.8 percent of water-borne diseases that are attributed to parasites.
In developing countries, 8 to 19 percent of diarrheal diseases can be attributed to cryptosporidium.
The high resistance of cryptosporidium oocysts to disinfectants such as chlorine bleach enables them to survive for long periods and remain infective outside of a host body.
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