Cryptosporidiosis: a brief literature review and update regarding Cryptosporidium in feces of Canada geese (Branta canadensis).* In recent years, laboratory-confirmed cases of cryptosporidiosis Cryptosporidiosis Definition Cryptosporidiosis refers to infection by the sporeforming protozoan known as Cryptosporidia. Protozoa are a group of parasites that infect the human intestine, and include the better known Giardia. have become increasingly evident in the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. . * Nevertheless, cryptosporidiosis may be under-diagnosed and under-reported. * In a 1999 nationwide survey of clinical laboratories, only 27 percent of respondents reported including testing for cryptosporidiosis in routine examinations of feces feces or excrement or stools Solid bodily waste discharged from the colon through the anus during defecation. Normal feces are 75% water. The rest is about 30% dead bacteria, 30% indigestible food matter, 10–20% cholesterol and other fats, for parasites. * As many as 300,000 cases of human cryptosporidiosis may occur each year in the United States. * Ninety percent of those cases may be attributed to use of contaminated contaminated, v 1. made radioactive by the addition of small quantities of radioactive material. 2. made contaminated by adding infective or radiographic materials. 3. an infective surface or object. water (including filtered and chlorinated chlorinated /chlo·ri·nat·ed/ (klor´i-nat?ed) treated or charged with chlorine. chlorinated charged with chlorine. chlorinated acids some, e.g. municipal supplies) or person-to-person transmission. * Ten percent may be attributed to foodborne transmission. * It has been estimated that between 65 and 97 percent of natural surface waters in the United States are contaminated with Cryptosporidium cryptosporidium (krĭp'tōspərĭd`ēəm), genus of protozoans having at least four species; they are waterborne parasites that cause the disease cryptosporidiosis. . * Surface water accounts for 62.5 percent of the public water supply in the United States. * The parasite has an oocyst oocyst /oo·cyst/ (-sist) the encysted or encapsulated ookinete in the wall of a mosquito's stomach; also, the analogous stage in the development of any sporozoan. o·o·cyst n. stage that is highly resistant to drying. * Cryptosporidium oocysts are not easily killed by chlorination chlorination Public health Addition of chlorinated compounds to drinking water as disinfectants. Cf Ozonation. . * Infection with Cryptosporidium is rarely fatal. * Most infected people are asymptomatic or, if symptomatic, recover with no therapeutic treatment. * Symptoms may vary from a self-limiting diarrhea in healthy people to severe and occasionally fatal diarrhea in immunocompromised immunocompromised /im·mu·no·com·pro·mised/ (-kom´pro-mizd) having the immune response attenuated by administration of immunosuppressive drugs, by irradiation, by malnutrition, or by certain disease processes (e.g., cancer). people. * Currently six to eight Cryptosporidium species are recognized. * C. parvum is the most widespread and important cause of cryptosporidiosis. * Two distinct genotypes of C. parvum have been identified in humans: -- Genotype genotype (jēn`ətīp'): see genetics. genotype Genetic makeup of an organism. The genotype determines the hereditary potentials and limitations of an individual. 1 (human genotype) has been observed only in human patients, and it is proposed that this genotype is transmitted from human to human. -- Genotype 2 (bovine genotype) has been observed in both calves and humans, and it is proposed that this genotype is transmitted from cattle to humans. * Recently, viable oocysts of C. parvum (bovine genotype) were isolated from feces of Canada geese. * It has been suggested that Canada geese may disseminate C. parvum oocysts into public water sources through their feces. * Canada geese nest in all 88 counties of Ohio. * Their numbers have increased from an estimated 18,000 in 1979 to an estimated 120,000 in 2001, a 500 percent increase. * The increase is attributed to the proliferation in urban and suburban areas of office buildings and apartment complexes with ponds and mowed landscapes. * Feces of Canada geese also litter the ground in many public areas such as parks, golf courses, cemeteries, and residential areas. * At 11 sites in the Toledo area, goose feces were tested for Cryptosporidium. * In 2000 and 2001, nine of 11 sites (81.8 percent) and nine of 10 sites (90 percent), respectively, were positive for Cryptosporidium. * Since cryptosporidiosis is under-suspected and under-diagnosed in the United States, health departments, hospitals, and laboratory personnel should develop procedures for the surveillance, detection, reporting, and prevention of cryptosporidiosis. * Public health officials should recognize the potential health risks associated with feces of Canada geese. |
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