{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T15:01:28Z","timestamp":1787238088603,"version":"build-2736575974"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,5,13]],"date-time":"2024-05-13T00:00:00Z","timestamp":1715558400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fapesp","award":["2014\/22827-7"],"award-info":[{"award-number":["2014\/22827-7"]}]},{"name":"Fapesp","award":["n. 2021\/12316-9"],"award-info":[{"award-number":["n. 2021\/12316-9"]}]},{"name":"Fapesp","award":["2020\/05758-2"],"award-info":[{"award-number":["2020\/05758-2"]}]},{"name":"Fapesp","award":["MR\/X0223358\/1"],"award-info":[{"award-number":["MR\/X0223358\/1"]}]},{"name":"Fapesp","award":["301275\/2019-0"],"award-info":[{"award-number":["301275\/2019-0"]}]},{"name":"MRC","award":["2014\/22827-7"],"award-info":[{"award-number":["2014\/22827-7"]}]},{"name":"MRC","award":["n. 2021\/12316-9"],"award-info":[{"award-number":["n. 2021\/12316-9"]}]},{"name":"MRC","award":["2020\/05758-2"],"award-info":[{"award-number":["2020\/05758-2"]}]},{"name":"MRC","award":["MR\/X0223358\/1"],"award-info":[{"award-number":["MR\/X0223358\/1"]}]},{"name":"MRC","award":["301275\/2019-0"],"award-info":[{"award-number":["301275\/2019-0"]}]},{"name":"Funda\u00e7\u00e3o Faculdade de Medicina","award":["2014\/22827-7"],"award-info":[{"award-number":["2014\/22827-7"]}]},{"name":"Funda\u00e7\u00e3o Faculdade de Medicina","award":["n. 2021\/12316-9"],"award-info":[{"award-number":["n. 2021\/12316-9"]}]},{"name":"Funda\u00e7\u00e3o Faculdade de Medicina","award":["2020\/05758-2"],"award-info":[{"award-number":["2020\/05758-2"]}]},{"name":"Funda\u00e7\u00e3o Faculdade de Medicina","award":["MR\/X0223358\/1"],"award-info":[{"award-number":["MR\/X0223358\/1"]}]},{"name":"Funda\u00e7\u00e3o Faculdade de Medicina","award":["301275\/2019-0"],"award-info":[{"award-number":["301275\/2019-0"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Several studies suggest that HTLV-1 infection may be associated with a wider spectrum of neurological and clinical manifestations that do not meet diagnostic criteria for HAM. These conditions may later progress to HAM or constitute an intermediate clinical form: intermediate syndrome (IS), a mid-point between asymptomatic HTLV-1 carriers and those with full myelopathy. Thus, we determined the incidence of HAM cases in the HTLV-1-asymptomatic and IS patients, and the clinical\/laboratory associated markers. A total of 204 HTLV-1-positive patients were included in this study, divided into two groups: Group 1, including 145 asymptomatic HTLV-1 subjects (ASY), and Group 2, including 59 patients with inflammatory clinical symptoms in more than three systems and a high proviral load (PVL). During a 60-month follow-up time, with the age ranging from 47 to 79 years, ten patients of the fifty-nine initially diagnosed as IS developed HAM (iHAM), and two patients of the initial 145 ASY developed HAM directly. Women were more prevalent in all groups. For the iHAM patients, the age ranged from 20 to 72 years, with a mean of 53 (\u00b115 SD). Older age was associated with the development of HAM, higher PVL and IS; however, there was no any specific symptom or clinical sign, that was associated with risk for iHAM. In conclusion, IS cases could be an early phase of development of HAM. These findings show the presence of higher incidence probabilities in our cohort than previously reported.<\/jats:p>","DOI":"10.3390\/pathogens13050403","type":"journal-article","created":{"date-parts":[[2024,5,14]],"date-time":"2024-05-14T03:20:29Z","timestamp":1715656829000},"page":"403","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["HTLV-1-Associated Myelopathy (HAM) Incidence in Asymptomatic Carriers and Intermediate Syndrome (IS) Patients"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8396-0263","authenticated-orcid":false,"given":"Rosa Maria do Nascimento","family":"Marcusso","sequence":"first","affiliation":[{"name":"Instituto de Infectologia Em\u00edlio Ribas, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0993-4523","authenticated-orcid":false,"given":"Tatiane","family":"Assone","sequence":"additional","affiliation":[{"name":"Departamento de Medicina Legal, Bio\u00e9tica, Medicina do Trabalho e Medicina F\u00edsica e Reabilita\u00e7\u00e3o, Faculdade de Medicina, Universidade de S\u00e3o Paulo, S\u00e3o Paulo 01246-000, Brazil"},{"name":"Departamento de Dermatologia, Faculdade de Medicina, Universidade de S\u00e3o Paulo, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3549-1992","authenticated-orcid":false,"given":"Michel E.","family":"Haziot","sequence":"additional","affiliation":[{"name":"Instituto de Infectologia Em\u00edlio Ribas, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jerusa","family":"Smid","sequence":"additional","affiliation":[{"name":"Instituto de Infectologia Em\u00edlio Ribas, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0114-7587","authenticated-orcid":false,"given":"Victor A.","family":"Folgosi","sequence":"additional","affiliation":[{"name":"Departamento de Dermatologia, Faculdade de Medicina, Universidade de S\u00e3o Paulo, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3922-5667","authenticated-orcid":false,"given":"Carolina","family":"Rosadas","sequence":"additional","affiliation":[{"name":"Section of Virology, Department of Infectious Disease, Imperial College London, London SW7 2BX, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4553-2559","authenticated-orcid":false,"given":"Jorge","family":"Casseb","sequence":"additional","affiliation":[{"name":"Departamento de Dermatologia, Faculdade de Medicina, Universidade de S\u00e3o Paulo, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Augusto C. Penalva","family":"de Oliveira","sequence":"additional","affiliation":[{"name":"Instituto de Infectologia Em\u00edlio Ribas, S\u00e3o Paulo 01246-000, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"the HTLV-1 Clinical Definition Working Group","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7415","DOI":"10.1073\/pnas.77.12.7415","article-title":"Detection and Isolation of Type C Retrovirus Particles from Fresh and Cultured Lymphocytes of a Patient with Cutaneous T-Cell Lymphoma","volume":"77","author":"Poiesz","year":"1980","journal-title":"Proc. Natl. Acad. Sci. 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