{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:16:18Z","timestamp":1792790178496,"version":"4.5.0"},"reference-count":69,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,8,28]],"date-time":"2020-08-28T00:00:00Z","timestamp":1598572800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Anhui Zhifei Longcom Biopharmaceutical Co., Ltd., China","award":["459677"],"award-info":[{"award-number":["459677"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Human noroviruses (HuNoVs) are the leading causative agents of epidemic and sporadic acute gastroenteritis that affect people of all ages worldwide. However, very few dose\u2013response studies have been carried out to determine the median infectious dose of HuNoVs. In this study, we evaluated the median infectious dose (ID50) and diarrhea dose (DD50) of the GII.4\/2003 variant of HuNoV (Cin-2) in the gnotobiotic pig model of HuNoV infection and disease. Using various mathematical approaches (Reed\u2013Muench, Dragstedt\u2013Behrens, Spearman\u2013Karber, logistic regression, and exponential and approximate beta-Poisson dose\u2013response models), we estimated the ID50 and DD50 to be between 2400\u20133400 RNA copies, and 21,000\u201338,000 RNA copies, respectively. Contemporary dose\u2013response models offer greater flexibility and accuracy in estimating ID50. In contrast to classical methods of endpoint estimation, dose\u2013response modelling allows seamless analyses of data that may include inconsistent dilution factors between doses or numbers of subjects per dose group, or small numbers of subjects. Although this investigation is consistent with state-of-the-art ID50 determinations and offers an advancement in clinical data analysis, it is important to underscore that such analyses remain confounded by pathogen aggregation. Regardless, challenging virus strain ID50 determination is crucial for identifying the true infectiousness of HuNoVs and for the accurate evaluation of protective efficacies in pre-clinical studies of therapeutics, vaccines and other prophylactics using this reliable animal model.<\/jats:p>","DOI":"10.3390\/v12090955","type":"journal-article","created":{"date-parts":[[2020,8,28]],"date-time":"2020-08-28T09:17:08Z","timestamp":1598606228000},"page":"955","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Evaluation of the 50% Infectious Dose of Human Norovirus Cin-2 in Gnotobiotic Pigs: A Comparison of Classical and Contemporary Methods for Endpoint Estimation"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4009-6823","authenticated-orcid":false,"given":"Ashwin K.","family":"Ramesh","sequence":"first","affiliation":[{"name":"Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24060, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0385-5592","authenticated-orcid":false,"given":"Viviana","family":"Parre\u00f1o","sequence":"additional","affiliation":[{"name":"Instituto de Virolog\u00eda, Instituto Nacional de Tecnolog\u00eda Agropecuaria (INTA), Castelar 1712, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip J.","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Water Science, Technology &amp; Policy Group, Department of Civil &amp; Environmental Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7332-6827","authenticated-orcid":false,"given":"Shaohua","family":"Lei","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24060, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weiming","family":"Zhong","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Cincinnati Children\u2019s Hospital Medical Center, Cincinnati, OH 45229, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xi","family":"Jiang","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Cincinnati Children\u2019s Hospital Medical Center, Cincinnati, OH 45229, USA"},{"name":"Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8295-0071","authenticated-orcid":false,"given":"Monica B.","family":"Emelko","sequence":"additional","affiliation":[{"name":"Water Science, Technology &amp; Policy Group, Department of Civil &amp; Environmental Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0709-5228","authenticated-orcid":false,"given":"Lijuan","family":"Yuan","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24060, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1056\/NEJMsa1206589","article-title":"Norovirus and Medically Attended Gastroenteritis in U.S. Children","volume":"368","author":"Payne","year":"2013","journal-title":"N. 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