{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T16:55:39Z","timestamp":1792515339480,"version":"4.5.0"},"reference-count":40,"publisher":"National Academy of Sciences","issue":"4","license":[{"start":{"date-parts":[[2021,1,7]],"date-time":"2021-01-07T00:00:00Z","timestamp":1609977600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["874850 MOOD"],"award-info":[{"award-number":["874850 MOOD"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"VRT Foundation, Trento, Italy","award":["Epidemiologia e transmissione di COVID-19 in Trentino"],"award-info":[{"award-number":["Epidemiologia e transmissione di COVID-19 in Trentino"]}]}],"content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2021,1,26]]},"abstract":"<jats:title>Significance<\/jats:title>\n                  <jats:p>We use a mathematical model to evaluate the Italian exit strategy after the lockdown imposed against the COVID-19 epidemics, comparing it to a number of alternative scenarios. We highlight that a successful reopening requires two critical conditions: a low value of the reproduction number and a low incidence of infection. The first is needed to allow some margin for expansion after the lifting of restrictions; the second is needed because the level of incidence will be maintained approximately constant after the reproduction number has grown to values close to one. Furthermore, we suggest that, even with significant reductions of transmission rates, resuming social contacts at prepandemic levels escalates quickly the COVID-19 burden.<\/jats:p>","DOI":"10.1073\/pnas.2019617118","type":"journal-article","created":{"date-parts":[[2021,1,7]],"date-time":"2021-01-07T16:15:24Z","timestamp":1610036124000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":81,"title":["Retrospective analysis of the Italian exit strategy from COVID-19 lockdown"],"prefix":"10.1073","volume":"118","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2842-7906","authenticated-orcid":false,"given":"Valentina","family":"Marziano","sequence":"first","affiliation":[{"name":"Center for Health Emergencies, Bruno Kessler Foundation, Trento 38123, 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