Cryptosporidiosis is an intestinal illness caused by a microscopic parasite called Cryptosporidium.
Although Cryptosporidium is not new, it was not recognized as a cause of human disease until 1976. Cryptosporidiosis was added to the list of reportable diseases in New York State in February 1994.
The number of cryptosporidiosis cases that occur each year is not yet well documented. Since the disease has recently been added to the list of reportable diseases, state and county health departments are now beginning to record the number and location of identified cases so that public health control measures can be developed. In 1994, 302 cases were reported to the New York State Department of Health. However, more cases may have occurred that were not detected, either because the Cryptosporidium stool test may not have been requested by the health care provider or the laboratory may have failed to use the necessary tests to identify it.
The most common symptom is diarrhea which is usually watery. It is often accompanied by abdominal cramping. Nausea, vomiting, fever, headache and loss of appetite may also occur. Some people infected with Cryptosporidium may not become ill.
All people are presumed susceptible to infection with Cryptosporidium. In healthy individuals with normal immune systems, signs and symptoms generally persist for two weeks or less. However, immunocompromised persons (those with weak immune systems) may have severe and long lasting illness. Some examples of immunocompromised people are those receiving cancer chemotherapy, kidney dialysis, steroid therapy, people with HIV/AIDS and patients with Crohnıs disease.
The incubation period may range from one to 12 days with an average of seven days.
Cryptosporidium is shed in the feces of infected humans and animals. People become infected by ingesting the organism. Cryptosporidium can be spread by person-to-person or animal-to-person contact and by drinking contaminated water. Infected individuals can shed the organism in their stool for several weeks after they recover from the illness. Because cryptosporidiosis is transmitted by the fecal-oral route, the greatest potential to transmit the organism comes from infected people who have diarrhea, people with poor personal hygiene and diapered children.
Some immunity appears to follow infection but the degree to which a previously infected person is immune to subsequent Cryptosporidium infection is unclear. Exposure to a large dose of the parasite could result in recurrent illness.
The infection is diagnosed by identifying the parasite during a microscopic examination of the stool. When a person with diarrheal illness is suspected of having cryptosporidiosis, the health practitioner should specifically request a Cryptosporidium test, since most laboratories do not yet routinely perform the necessary tests needed to identify this particular microscopic parasite. A cryptosporidium test should specifically be ordered for people with HIV/AIDS or other immunocompromised patients (for example,cancer or transplant patients) who are being treated for diarrhea.
There is no specific treatment for cryptosporidiosis. However, some patients may respond to certain antibiotics. Oral liquids or intravenous fluids are sometimes necessary if dehydration occurs. Anti-diarrheal drugs which reduce the motion of the intestines may provide some temporary improvement. Patients with cryptosporidiosis should obtain nutritional counseling through their health care provider to discuss their diet and how best to minimize the symptoms of their diarrhea.
You can minimize the chances of acquiring and spreading the infection by thoroughly washing your hands after using the toilet, changing diapers or coming into contact with fecal material in any way. Because cattle are a common source of Cryptosporidium, do not drink raw milk and be sure to wash your hands thoroughly after contact with cattle or other farm animals. Avoid drinking untreated and inadequately filtered surface water when camping or when traveling in developing countries. Comply with any water advisory issued by local and state authorities.
It is believed that Cryptosporidium has always been present to some degree in water. Recently, it has been found in low numbers in some drinking waters derived from surface water sources (streams, lakes or reservoirs) in New York State and across the nation. There have been no waterborne outbreaks of cryptosporidiosis identified in New York State. Only laboratories with specialized testing capabilities can detect the presence of Cryptosporidium cysts in water. Laboratory tests are not very reliable at this time and they cannot tell whether the cyst is alive or dead.
Because cryptosporidiosis can be a severe disease in immunocompromised persons, such individuals should discuss the need for extra precautions with their health care provider to minimize their risk of infection. Contaminated drinking water is only one of a number of ways in which cryptosporidiosis can be acquired. Here are some suggested steps to reduce risk of infection:
For additional information, contact your health care provider or your local or state health department.
Updated: April 1996
Source: NY State Department of Health