{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T18:12:28Z","timestamp":1789582348580,"version":"build-2803163510"},"reference-count":36,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2015,1,7]]},"abstract":"<jats:p>Although <jats:italic>Cryptosporidium parvum<\/jats:italic> and <jats:italic>C. hominis<\/jats:italic> cause the majority of human cryptosporidiosis cases, other <jats:italic>Cryptosporidium<\/jats:italic> species are also capable of infecting humans, particularly when individuals are immunocompromised. Ten <jats:italic>C. muris<\/jats:italic> cases have been reported, primarily in human immunodeficiency virus (HIV) -positive patients with diarrhea. However, asymptomatic cases were reported in two HIV-negative children, and in another case, age and immune status were not described. This study examines the infectivity of <jats:italic>C. muris<\/jats:italic> in six healthy adults. Volunteers were challenged with 10<jats:sup>5<\/jats:sup> <jats:italic>C. muris<\/jats:italic> oocysts and monitored for 6 weeks for infection and\/or illness. All six patients became infected. Two patients experienced a self-limited diarrheal illness. Total oocysts shed during the study ranged from 6.7 \u00d7 10<jats:sup>6<\/jats:sup> to 4.1 \u00d7 10<jats:sup>8<\/jats:sup>, and the number was slightly higher in volunteers with diarrhea (2.8 \u00d7 10<jats:sup>8<\/jats:sup>) than asymptomatic shedders (4.4 \u00d7 10<jats:sup>7<\/jats:sup>). <jats:italic>C. muris<\/jats:italic>-infected subjects shed oocysts longer than occurred with other species studied in healthy volunteers. Three volunteers shed oocysts for 7 months. Physical examinations were normal, with no reported recurrence of diarrhea or other gastrointestinal complaints. Two persistent shedders were treated with nitazoxanide, and the infection was resolved. Thus, healthy adults are susceptible to <jats:italic>C. muris<\/jats:italic>, which can cause mild diarrhea and result in persistent, asymptomatic infection.<\/jats:p>","DOI":"10.4269\/ajtmh.14-0525","type":"journal-article","created":{"date-parts":[[2014,10,14]],"date-time":"2014-10-14T03:10:13Z","timestamp":1413256213000},"page":"50-55","source":"Crossref","is-referenced-by-count":44,"title":["Cryptosporidium muris: Infectivity and Illness in Healthy Adult Volunteers"],"prefix":"10.4269","volume":"92","author":[{"given":"Cynthia L.","family":"Chappell","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pablo C.","family":"Okhuysen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rebecca C.","family":"Langer-Curry","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip J.","family":"Lupo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Widmer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saul","family":"Tzipori","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2795","reference":[{"key":"R1","series-title":"Proc Soc Exp Biol Med","first-page":"12","article-title":"A sporozoan found in the peptic glands of the common mouse","volume":"5","author":"Tyzzer","year":"1907"},{"key":"R2","series-title":"Gastroenterology","first-page":"1156","article-title":"Overwhelming watery diarrhea associated with a Cryptosporidium in an immunosuppressed patient","volume":"70","author":"Meisel","year":"1976"},{"key":"R3","series-title":"Gastroenterology","first-page":"592","article-title":"Acute enterocolitis in a human being infected with the protozoan Cryptosporidium","volume":"70","author":"Nime","year":"1976"},{"key":"R4","series-title":"J Clin Microbiol","first-page":"3472","article-title":"Molecular characterization of Cryptosporidium isolates obtained from humans in France","volume":"39","author":"Guyot","year":"2001"},{"key":"R5","series-title":"Trop Med Int Health","first-page":"357","article-title":"Molecular analysis of Cryptosporidium species isolated from HIV-infected patients in Thailand","volume":"7","author":"Tiangtip","year":"2002"},{"key":"R6","series-title":"Emerg Infect Dis","first-page":"204","article-title":"Cryptosporidium muris infection in an HIV-infected adult, Kenya","volume":"8","author":"Gatei","year":"2002"},{"key":"R7","series-title":"Emerg Infect Dis","first-page":"1174","article-title":"Cryptosporidium muris, a rodent pathogen, recovered from a human in Peru","volume":"9","author":"Palmer","year":"2003"},{"key":"R8","series-title":"J Clin Microbiol","first-page":"632","article-title":"Multilocus genotyping of Cryptosporidium sp. isolates from human immunodeficiency virus-infected individuals in South India","volume":"44","author":"Muthusamy","year":"2006"},{"key":"R9","series-title":"Mol Biol (Mosk)","first-page":"934","article-title":"The identification of Cryptosporidium species (protozoa) in Ifsahan, Iran by PCR-RFLP analysis of the 18S rRNA gene","volume":"41","author":"Azami","year":"2007"},{"key":"R10","series-title":"Rev Chilena Infectol","first-page":"63","article-title":"Especies de Cryptosporidum en pacientes inmunodeficientes e inmunocompetentes de Valpara\u00edso. Estudio descriptivo","volume":"29","author":"Neira-O","year":"2012"},{"key":"R11","series-title":"Vet Parasitol","first-page":"129","article-title":"Natural Cryptosporidium muris infection of the stomach in laboratory mice","volume":"55","author":"Ozkul","year":"1994"},{"key":"R12","series-title":"Vet Parasitol","first-page":"41","article-title":"The pathogenesis of experimental infections of Cryptosporidium muris (strain RN 66) in outbred nude mice","volume":"86","author":"Taylor","year":"1999"},{"key":"R13","series-title":"Cryptosporidiosis of Man and Animals","first-page":"199","year":"1990"},{"key":"R14","series-title":"Vet Pathol","first-page":"363","article-title":"Cryptosporidium muris-like infection in stomach of cynomolgus monkeys (Macaca fascicularis)","volume":"39","author":"Dubey","year":"2002"},{"key":"R15","series-title":"Parasitol Res","first-page":"218","article-title":"Infectivity of Cryptosporidium muris (strain RN66) in various laboratory animals","volume":"75","author":"Iseki","year":"1989"},{"key":"R16","series-title":"Am J Trop Med Hyg","first-page":"70","article-title":"Short report: possible Cryptosporidium muris infection in humans","volume":"62","author":"Katsumata","year":"2000"},{"key":"R17","series-title":"J Egypt Soc Parasitol","first-page":"645","article-title":"Multilocus genetic analysis of Cryptosporidium isolates from Saudi Arabia","volume":"38","author":"Al-Brikan","year":"2008"},{"key":"R18","series-title":"Appl Environ Microbiol","first-page":"4477","article-title":"Sequence polymorphism in the \u03b2-tubulin gene reveals heterogeneous and variable population structures in Cryptosporidium parvum","volume":"64","author":"Widmer","year":"1998"},{"key":"R19","series-title":"Infect Immun","first-page":"5670","article-title":"Genetic analysis of a Cryptosporidium parvum human genotype 1 isolate passaged through different host species","volume":"70","author":"Akiyoshi","year":"2002"},{"key":"R20","series-title":"Methods Mol Biol","first-page":"177","article-title":"Genotyping of Cryptosporidium parvum with microsatellite markers","volume":"268","author":"Widmer","year":"2004"},{"key":"R21","series-title":"N Engl J Med","first-page":"855","article-title":"The infectivity of Cryptosporidium parvum in healthy volunteers","volume":"332","author":"DuPont","year":"1995"},{"key":"R22","series-title":"Cryptosporidium: From Molecules to Disease","first-page":"19","article-title":"Cryptosporidium parvum: infectivity, pathogenesis and the host-parasite relationship","author":"Chappell","year":"2004"},{"key":"R23","series-title":"Am J Trop Med Hyg","first-page":"851","article-title":"Cryptosporidium hominis: experimental challenge of healthy adults","volume":"75","author":"Chappell","year":"2006"},{"key":"R24","series-title":"Am J Trop Med Hyg","first-page":"238","article-title":"Cryptosporidium meleagridis: infectivity in healthy adult volunteers","volume":"85","author":"Chappell","year":"2011"},{"key":"R25","series-title":"Am J Trop Med Hyg","first-page":"917","article-title":"Cryptosporidium muris in a Texas canine population","volume":"78","author":"Lupo","year":"2008"},{"key":"R26","series-title":"Appl Environ Microbiol","first-page":"3386","article-title":"Genetic diversity within Cryptosporidium parvum and related Cryptosporidium species","volume":"65","author":"Xiao","year":"1999"},{"key":"R27","series-title":"Appl Environ Microbiol","first-page":"1578","article-title":"Phylogenetic analysis of Cryptosporidium parasites based on the small-subunit rRNA gene locus","volume":"65","author":"Xiao","year":"1999"},{"key":"R28","series-title":"Arch Intern Med","first-page":"894","article-title":"Serological evidence of Cryptosporidium infection in US volunteers before and during Peace Corp service in Africa","volume":"149","author":"Ungar","year":"1989"},{"key":"R29","series-title":"J Infect Dis","first-page":"1275","article-title":"Virulence of three distinct Cryptosporidium parvum isolates for healthy adults","volume":"180","author":"Okhuysen","year":"1999"},{"key":"R30","series-title":"J Infect Dis","first-page":"1320","article-title":"Infectivity of a Cryptosporidium parvum isolate of cervine origin for healthy adults and interferon-\u03b3 knockout mice","volume":"185","author":"Okhuysen","year":"2002"},{"key":"R31","series-title":"Am J Trop Med Hyg","first-page":"157","article-title":"Infectivity of Cryptosporidium parvum in healthy adults with pre-existing anti-C. parvum serum immunoglobulin G","volume":"60","author":"Chappell","year":"1999"},{"key":"R32","series-title":"Lancet","first-page":"1375","article-title":"Effect of nitazoxanide on morbidity and mortality in Zambian children with cryptosporidiosis: a randomised controlled trial","volume":"360","author":"Amadi","year":"2002"},{"key":"R33","series-title":"Am J Trop Med 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