{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T05:24:26Z","timestamp":1787808266869,"version":"build-2784847793"},"reference-count":23,"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><jats:italic>Cryptosporidium<\/jats:italic> is an important diarrhea-associated pathogen, however the correlation between parasite burden and diarrhea severity remains unclear. We studied this relationship in 10 experimentally infected calves using immunofluorescence microscopy and real-time polymerase chain reaction (qPCR) (<jats:italic>N<\/jats:italic> = 124 fecal samples). The qPCR data were corrected for extraction\/amplification efficiency and gene copy number to generate parasite counts. The qPCR and microscopic oocyst quantities exhibited significant correlation (R<jats:sup>2<\/jats:sup> = 0.33, <jats:italic>P<\/jats:italic> &lt; 0.05), however qPCR had increased sensitivity. Upon comparison with diarrhea severity scores (from 0 to 3), a PCR-based count of \u2265 2.6 \u00d7 10<jats:sup>5<\/jats:sup> parasites or an immunofluorescence microscopy count of \u2265 4.5 \u00d7 10<jats:sup>4<\/jats:sup> oocysts were discriminatory predictors of moderate-to-severe diarrhea (versus no-to-mild diarrhea), with accuracies and predictive values of 72\u201382%. In summary, a quantitative approach for <jats:italic>Cryptosporidium<\/jats:italic> can refine predictive power for diarrhea and appears useful for distinguishing clinical cryptosporidiosis versus subclinical infection.<\/jats:p>","DOI":"10.4269\/ajtmh.14-0488","type":"journal-article","created":{"date-parts":[[2014,11,5]],"date-time":"2014-11-05T04:16:38Z","timestamp":1415160998000},"page":"45-49","source":"Crossref","is-referenced-by-count":28,"title":["Correlation Between Diarrhea Severity and Oocyst Count via Quantitative PCR or Fluorescence Microscopy in Experimental Cryptosporidiosis in Calves"],"prefix":"10.4269","volume":"92","author":[{"given":"Darwin J.","family":"Operario","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren 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