{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T14:41:53Z","timestamp":1787236913535,"version":"build-2736575974"},"reference-count":25,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[2025,6,26]],"date-time":"2025-06-26T00:00:00Z","timestamp":1750896000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon Europe Framework Programme"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,11,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Acute gastroenteritis outbreaks caused by noroviruses are a common public health issue on cruise ships. Understanding the main drivers of sustained outbreaks is critical for evaluating the effectiveness of preventive interventions such as the isolation of infected individuals.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We analysed a line-list of 121 cases from a norovirus outbreak on a cruise visiting Mediterranean ports (cumulative incidence among passengers 9.7%). We used a Bayesian inference model to reconstruct likely transmission chains, taking into account different transmission settings and the isolation of cases after diagnosis. We then calibrated a branching process model to simulate alternative isolation scenarios and estimate their effectiveness in reducing transmission.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Reconstructed transmission chains revealed a high heterogeneity in individual transmission, with 57% [95% credible interval (CrI): 48\u201365%] of secondary cases caused by 10% of infected individuals (here termed \u2018superspreaders\u2019). Superspreaders exhibited longer diagnostic delays (mean 83\u00a0hours, 95% CrI: 70\u201396\u00a0hours) compared to other infectors (mean 47\u00a0hours, 95% CrI: 44\u201350\u00a0hours) and a halved frequency of vomiting and diarrhoea episodes. The 72-hour isolation protocol implemented during the outbreak averted 71% of potential cases compared to a no-intervention scenario, halving the effective reproduction number from 9.8 (95% CrI of the mean: 7.1\u201312.7) to 4.9 (95% CrI: 3.0\u20137.1). Reducing diagnostic delays further reduced the effective reproduction number, resulting in lower case numbers and probability of sustained outbreaks.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Timely diagnosis and isolation have a remarkable impact on norovirus containment on cruise ship outbreaks. Targeted information campaigns encouraging passengers to seek immediate medical assistance upon gastrointestinal symptoms can significantly improve outbreak management.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jtm\/taaf059","type":"journal-article","created":{"date-parts":[[2025,6,26]],"date-time":"2025-06-26T07:59:23Z","timestamp":1750924763000},"source":"Crossref","is-referenced-by-count":3,"title":["Mitigating norovirus spread on cruise ships: a model-based assessment of diagnostic timing and isolation"],"prefix":"10.1093","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8903-5685","authenticated-orcid":false,"given":"Alfredo","family":"De Bellis","sequence":"first","affiliation":[{"name":"Center for Health Emergencies, Fondazione Bruno Kessler , Trento, 38123 ,","place":["Italy"]},{"name":"Department of Mathematics, University of Trento , Trento, 38123 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