{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T15:15:58Z","timestamp":1787584558329,"version":"build-2736575974"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,4,26]],"date-time":"2024-04-26T00:00:00Z","timestamp":1714089600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>A natural monkeypox virus infection may not induce sufficient neutralizing antibody responses in a subset of healthy individuals. The aim of this study was to evaluate monkeypox virus-neutralizing antibodies six months after infection and to assess the virological factors predictive of a poor immunological response. Antibodies were assessed using a plaque reduction neutralization test at six months from mpox infection; mpox cutaneous, oropharyngeal, and anal swabs, semen, and plasma samples were tested during infection. Overall, 95 people were included in the study; all developed detectable antibodies. People who were positive for the monkeypox virus for more days had higher levels of antibodies when considering all tested samples (p = 0.029) and all swabs (p = 0.005). Mpox cycle threshold values were not predictive of antibody titers. This study found that the overall days of monkeypox virus detection in the body, irrespective of the viral loads, were directly correlated with monkeypox virus neutralizing antibodies at six months after infection.<\/jats:p>","DOI":"10.3390\/v16050681","type":"journal-article","created":{"date-parts":[[2024,4,26]],"date-time":"2024-04-26T09:26:02Z","timestamp":1714123562000},"page":"681","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Monkeypox Virus Neutralizing Antibodies at Six Months from Mpox Infection: Virologic Factors Associated with Poor Immunologic Response"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7811-6255","authenticated-orcid":false,"given":"Angelo Roberto","family":"Raccagni","sequence":"first","affiliation":[{"name":"Infectious Diseases Unit, Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1490-636X","authenticated-orcid":false,"given":"Alessandro","family":"Mancon","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology, Virology and Bioemergencies, Ospedale Sacco, 20157 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-2559-7042","authenticated-orcid":false,"given":"Sara","family":"Diotallevi","sequence":"additional","affiliation":[{"name":"Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2447-6498","authenticated-orcid":false,"given":"Riccardo","family":"Lolatto","sequence":"additional","affiliation":[{"name":"Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Bruzzesi","sequence":"additional","affiliation":[{"name":"Infectious Diseases Unit, Vita-Salute San Raffaele University, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Rita","family":"Gismondo","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology, Virology and Bioemergencies, Ospedale Sacco, 20157 Milan, Italy"},{"name":"Laboratory of Clinical Microbiology, Virology and Bioemergencies, University of Milan, 20157 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonella","family":"Castagna","sequence":"additional","affiliation":[{"name":"Infectious Diseases Unit, Vita-Salute San Raffaele University, 20132 Milan, Italy"},{"name":"Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9414-0287","authenticated-orcid":false,"given":"Davide","family":"Mileto","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology, Virology and Bioemergencies, Ospedale Sacco, 20157 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2673-2731","authenticated-orcid":false,"given":"Silvia","family":"Nozza","sequence":"additional","affiliation":[{"name":"Infectious Diseases Unit, Vita-Salute San Raffaele University, 20132 Milan, Italy"},{"name":"Infectious Diseases Unit, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"679","DOI":"10.1056\/NEJMoa2207323","article-title":"Monkeypox Virus Infection in Humans across 16 Countries\u2014April\u2013June 2022","volume":"387","author":"Thornhill","year":"2022","journal-title":"N. 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