Cryptosporidiosis - Exposure Risks

Exposure Risks

Cryptosporidiosis is found worldwide. It causes 50.8% of water-borne diseases that are attributed to parasites. In developing countries, 8-19% of diarrheal diseases can be attributed to Cryptosporidium. Ten percent of the population in developing countries excretes oocysts. In developed countries, the number is lower at 1-3%. The age group most affected is children from 1 to 9 years old.

The following groups have an elevated risk of being exposed to Cryptosporidium:

• People who swim regularly in pools with insufficient sanitation (certain strains of Cryptosporidium are chlorine-resistant)
• Child care workers
• Parents of infected children
• People who take care of other people with cryptosporidiosis
• International travelers
• Backpackers, hikers, and campers who drink unfiltered, untreated water
• People, including swimmers, who swallow water from contaminated sources
• People who handle infected cattle
• People exposed to human feces through sexual contact

Cases of cryptosporidiosis can occur in a city that does not have a contaminated water supply. In a city with clean water, it may be that cases of cryptosporidiosis have different origins. Testing of water, as well as epidemiological study, are necessary to determine the sources of specific infections. Note that Cryptosporidium typically does not cause serious illness in healthy people. It may chronically sicken some children, as well as adults who are exposed and immunocompromised. A subset of the immunocompromised population is people with AIDS. Some sexual behaviours can transmit the parasite directly.

Statistics for the United States - number of cases: