Htlv-1 Infection in Patients With Neurological Manifestations in Northeast Brazil

Htlv-1 Infection in Patients With Neurological Manifestations in Northeast Brazil | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Htlv-1 Infection in Patients With Neurological Manifestations in Northeast Brazil Artur Fernando Soares da Silva, Yan Charles da Silva Bastos, Juliana Tiemi Oikawa, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8842050/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 9 You are reading this latest preprint version Abstract Human T-lymphotropic virus (HTLV) infection is associated with a broad spectrum of neurological manifestations, including conditions that may precede the development of HTLV-1–associated myelopathy/tropical spastic paraparesis. This analytical cross-sectional study aimed to estimate the prevalence of HTLV-1 infection and describe associated sociodemographic, socioeconomic, behavioral, and clinical characteristics among patients with neurological disorders followed at a tertiary public hospital in Northeast Brazil between 2024 and 2025. A total of 300 patients underwent serological screening using an immunoenzymatic assay with a commercial kit (Murex HTLV-I + II-Diasorin UK), and molecular confirmation by polymerase chain reaction for positive or indeterminate samples using a commercial kit (HiPurA Blood Genomic DNA Miniprep Purification). Three patients tested positive for HTLV-1 infection, resulting in an overall prevalence of 1.0%. All individuals who tested positive for HTLV-1 were women aged 43 to 72 years, with low educational level and income. Univariate analyses identified significant associations with injection drug use, history of blood transfusion, and family history of HTLV-1/2. Clinically, HTLV-1 positive patients presented heterogeneous neurological manifestations, ranging from urinary dysfunction and lower limb sensory and motor impairment to musculoskeletal and inflammatory symptoms, compatible with early or intermediate neurological syndrome. These findings highlight the presence of HTLV-1 infection among neurological patients and reinforce the importance of targeted screening in this population. Early identification of HTLV-1 may contribute to improved clinical management and support public health strategies aimed at preventing disease progression and reducing underdiagnosis in endemic regions. Human T-lymphotropic virus type 1 Neurological Disorders HTLV-1–associated myelopathy Epidemiology Introduction The Human T-lymphotropic Virus (HTLV) was the first oncogenic retrovirus identified in humans in 1977 and it is primarily transmitted through sexual contact, vertical transmission, and blood exposure (World Health Organization 2023). Among its types, HTLV-1 is the most significant, with an estimated 5 to 10 million infected individuals worldwide and between 800,000 to 2.5 million in Brazil, and it is associated with a broad spectrum of clinical manifestations, particularly neurological disorders. The main neurological condition related to HTLV-1 infection is HTLV-1–associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic, progressive inflammatory disease of the central nervous system (Lima et al. 2021). In addition to HAM/TSP, HTLV-1 infection may present with other neurological manifestations, including cognitive dysfunction, encephalopathies, neurogenic bladder, and myopathies, which may occur in isolation and vary according to the individual and duration of infection (Ferreira et al. 2024; Araújo and Wedemann 2019). Given the slow and insidious progression of HAM/TSP, literature has described the presence of nonspecific neurological manifestations associated with HTLV-1 that precede the development of classical myelopathy. This set of alterations has been referred as Intermediate Syndrome (IS) and encompasses neurological manifestations that do not yet fulfill the diagnostic criteria for HAM/TSP but already indicate involvement of the central nervous system. Recognition of IS is essential for the early identification of HTLV-1–associated neurological involvement and for the implementation of a more appropriate clinical approach (Marcusso et al. 2024). In patients presenting with neurological manifestations, HTLV-1 infection is of particular relevance due to its association with HAM/TSP and with neurological conditions compatible with Intermediate Syndrome, which are often underdiagnosed and exhibit a progressive course (Gascon et al. 2019; Yamauchi et al. 2021). However, the scarcity of regional epidemiological data and the underreporting of HTLV-1 infection hinder accurate estimates of its true magnitude, especially in endemic areas such as Northeast Brazil (Rosadas et al. 2020). The aim of this study was to estimate the prevalence of HTLV-1/2 infection and associated factors among patients with neurological disorders treated at a public hospital in the state of Pernambuco, Brazil, in 2025. Additionally, we sought to describe the sociodemographic, socioeconomic, behavioral, and clinical profiles of HTLV-positive patients, in order to support timely diagnosis, appropriate clinical management, and the strengthening of public health policies for screening and follow-up. Results The study included 300 patients with neurological manifestations who underwent serological testing for HTLV-1/2 infection, with subsequent molecular confirmation. Of these, three tested positive for HTLV-1, resulting in an overall prevalence of 1.0% (3/300). The results of the univariate analysis of sociodemographic, socioeconomic, and behavioral variables of the overall study population, including all the positive cases, are summarized in Table 1. Table 1. Distribution of sociodemographic, socioeconomic, and behavioral variables of the study population. SOCIODEMOGRAPHIC VARIABLES Variables No. of positive cases No. of negative cases % 95% CI P-Value Place of residence 1.000 1. Metropolitan Region of Recife (MRR) 2 165 55.67% 50.01-61.18% 2. Inland areas of the state 1 129 43.33% 37.85–48.99% 3. Not reported 0 3 1% 0.34-2.90% Sex at birth 0.179 1.Female 2.Male 3 0 185 112 62.67% 37.33% 57.07-67.95% 32.05-42.93% Age group (years) 0.592 1. 18–29 years 2. 30–60 years 3. ≥ 61 years 0 1 2 28 153 116 9.33% 51.33% 39.33% 6.54-13.16% 45.70-56.94% 33.97-44.96% Ethnicity 0.282 1. White 2. Black 3. Mixed Race (Pardo) 2 1 0 103 58 136 35.00% 19.67% 45.33% 29.82-40.56% 15.56-24.54% 39.79-50.99% Marital status 0.068 1. Single 2. Married / Stable union 3. Widowed / Divorced 3 0 0 105 145 47 36.00% 48.33% 15.67% 30.78-41.58% 42.74-53.97% 11.99-20.21% SOCIOECONOMIC VARIABLES Variables No. of positive cases No. of negative cases % 95% CI P-Value Education level 0.817 1. Illiterate 0 29 9.67% 6.81-13.54% 2. Incomplete / complete Primary education 2 133 45.00% 39.47-50.66% 3. Incomplete / complete secondary education 1 104 34.67% 29.51-40.22% 4. Higher education / postgraduate studies 0 32 10.67% 7.66-14.67% Income 0.822 1. No income 2. < one minimum wage 3. one minimum wage 4. two minimum wage 5. three or more minimum wage 6. Not reported 0 0 3 0 0 0 57 26 171 19 23 1 19.00% 8.67% 58.00% 6.33% 7.67% 0.33% 14.96-23.82% 5.98-12.40% 52.35-63.45% 4.09-9.68% 5.16-11.24% 0.06-1.86% BEHAVIORAL VARIABLES Variables No. of positive cases No. of negative cases % 95% CI P-Value History of intravenous drug use 0.020 1. YES 2. NO 1 2 1 296 0.67% 99.33% 0.18-2.40% 97.60-99.82% Age at sexual debut 0.305 1. No previous sexual activity 2. ≤ 18 years 3. ≥ 19 years 4. Not reported 1 1 1 0 16 172 96 13 5.67% 57.66% 32.33% 4.34% 3.34-8.91% 51.87-63.24% 27.07-37.93% 2.32-7.28% Condom use 1.000 1. YES 2. NO 0 2 91 190 32.15% 67.85% 26.7-37.9% 62.1-73.3% History of multiple sexual partners 0.346 1. YES 2. NO 1 1 53 228 19.08% 80.91% 14.7- 24.1% 75.9- 85.3% History of blood transfusion 0.045 1. YES 2. NO 2 1 37 260 13% 87% 9.66-17.28% 82.72-90.34% Family history of HTLV infection 0.020 1. YES 2. NO 1 2 1 296 0.67% 99.33% 0.18-2.40% 97.60-99.82% History of breastfeeding 0.250 1. YES 2. NO 3. Does not know / does not remember 2 1 0 228 22 47 76.67% 7.67% 15.67% 71.56-81.10% 5.16-11.24% 11.99-20.21% Detailed sociodemographic and socioeconomic characteristics of the three HTLV-1–positive patients are presented in Table 2, while behavioral and clinical characteristics, including neurological manifestations and potential exposure factors, are summarized in Table 3. Table 2. Sociodemographic and socioeconomic characteristics of neurological patients investigated for HTLV infection at a tertiary hospital in Northeast Brazil Pacient Sex at birth Age Race Marital Status Occupation Residence Income Education Level 1 Feminine 67y White Single Retired Recife BRL 1412 Incomplete primary education 2 Feminine 43y Black Single Retired Camaragibe BRL 1412 High school 3 Feminine 72y White Single Retired Garanhuns BRL 1412 Incomplete primary education *BRL = Brazilian Real. Table 3. Behavioral and clinical characteristics of neurological patients investigated for HTLV infection at a tertiary hospital in Northeast Brazil Pacient Injecting drug use First Sexual Intercourse Multiple sexual partners Use of Condoms Blood transfusion Breastfed Neurological manifestation 1 NO 14y YES NO YES, 2003 YES Paresthesia in the lower limbs; urinary incontinence. 2 NO 21y NO NO NO YES Lower limb paralysis; neurogenic bladder. 3 YES No history of sexual activity - - YES, 1988 NO Vertigo; Syncope; Fibromyalgia; Lumbosciatica and Cervicalgia. Discussion The prevalence of HTLV-1 infection of 1.0% observed among neurological patients in this study represents one of the first reports of HTLV-1 prevalence in this specific population in Brazil. This finding corroborates with results from studies conducted in other populations, such as pregnant women, among whom a prevalence of 0.49% has been reported by Leal et al. (2025), and Lima et al. (2021) in blood donors, for whom the national mean prevalence was estimated at 0.41%. The univariate analyses identified some statistically significant associations, however, these findings should be interpreted with caution, because there was no control for potential confounding factors. Additionally, due to the small number of positive cases, the multivariate analysis was not realized. Variables related to known HTLV transmission routes, such as injection drug use and a history of blood transfusion, showed statistical association with viral infection. Prior knowledge of HTLV, including the presence of a family history, was also statistically significant in the univariate analysis. These findings are consistent with risk factors discussed by Saab et al. (2024), with a case of HAM/TSP. Regarding the sociodemographic and socioeconomic characteristics of HTLV-1–positive participants (Table 2 ), all three patients were female, aged between 43 and 72 years, in agreement with studies reporting a higher occurrence of HTLV-1 among women, especially older ones, possibly due to cumulative exposure risk over time (Rosadas et al., 2021). All the positive participants reported a monthly income equivalent to one minimum wage, and educational levels ranged from incomplete elementary education to completed secondary education, characteristics commonly observed in populations assisted by public health services and previously described in HTLV studies conducted in Brazil (Rosadas et al., 2020). Sexual transmission is recognized as one of the main routes of HTLV dissemination in Brazil, particularly in contexts involving unprotected sexual intercourse and multiple partners (Altieri et al., 2025; Eusébio-Ponce et al., 2019). In this study, two participants reported having initiated sexual activity at 14 and 21 years of age and not using condoms, additionally both were single, and one had a history of multiple sexual partners. It was not possible to establish an association between age at sexual debut and increased risk of HTLV infection, in contrast to findings from other studies that report higher risk associated with early sexual initiation (Leal et al., 2025). Regarding blood-borne and vertical transmission routes of the three positive participants, one patient reported a history of injection drug use, a transmission route of HTLV previously described in the literature by Altieri et al. (2025). Two patients reported having received blood transfusions during surgical procedures in 2003 and 1988, respectively. In Brazil, routine screening of blood donors for HTLV has been mandatory since 1993 (Rosadas et al., 2021), and the Ministry of Health (2021) considers individuals who received transfusions prior to 1993 as a vulnerable population. In the case of the patient who received a transfusion in 1988, when HTLV testing was not mandatory, blood transfusion represents the most likely route of viral transmission. Two of the three HTLV-positive patients reported having been breastfed, among them, one had a family history of HTLV, with an infected mother. This finding is relevant, as it suggests that this was the route of infection for HTLV-1. Vertical transmission represents an important route of HTLV-1 transmission and occurs predominantly through breastfeeding according to Rosadas et al. (2020). With regard to the clinical profile and neurological manifestations of HTLV-positive participants described in Table 3 , two HTLV-1–positive patients presented urinary symptoms combined with lower limb impairment, characteristic of HTLV infection, differing in severity and duration. Haziot et al. (2019) described that for a clinical condition to be considered Intermediate Syndrome (IS), the patient must present more than three signs found during a neurological evaluation, where the investigator is unaware of the patient's HTLV infection, the patient at an earlier disease stage reported paresthesia in the lower limbs, characterized by numbness, in addition to urinary incontinence, with symptom onset approximately two years prior, coinciding with the beginning of follow-up at the study site, but it was still under investigation regarding the presence of infection, being classified as an IS based on the results of this study. In contrast, the participant with more advanced disease, although attending her first neurology outpatient visit, had a prior diagnosis of HTLV infection and presented more severe neurological manifestations, including lower limb paralysis and a history of neurogenic bladder since 2012, characteristic of a defined HAM/TSP case described in the literature (Haziot et al. 2019). The third participant, despite reporting less typical neurological symptoms such as dizziness and nausea, also presented inflammatory manifestations, including lumbar and cervical pain, as well as musculoskeletal conditions such as fibromyalgia. This finding is consistent with the study by Silva et al. (2024), which described rheumatological alterations, including fibromyalgia, in patients infected with HTLV-1/2, and considering the absence of a previous diagnosis for HTLV infection, she can be also classified as IS according to the results of this study. In conclusion, the diversity of clinical presentations observed in this study, together with variability in disease severity, highlights the broad spectrum of neurological impairment associated with HTLV-1 infection. This investigation contributes to filling important information gaps and may support public health policies aimed at patients with neurological manifestations associated with HTLV-1 in Pernambuco, emphasizing the need for greater attention to neurological conditions that precede HAM/TSP and fall within the Intermediate Syndrome spectrum. Methods An analytical cross-sectional study was conducted among patients with neurological disorders followed at a tertiary university hospital in Northeast Brazil between 2024 and 2025. Participants provided written informed consent and completed structured interviews to collect sociodemographic, socioeconomic, behavioral, and clinical data. Peripheral blood samples were collected and analyzed at the Virology Laboratory of the Keizo Asami Institute (iLIKA-UFPE) using an enzyme-linked immunosorbent assay (ELISA) for screening of HTLV-1/2 infection with the commercial Diasorin Murex HTLV-1 + 2 kit. Samples with positive or indeterminate ELISA results underwent molecular detection using polymerase chain reaction (PCR) using the HiPurA Blood Genomic DNA Miniprep Purification kit. The minimum sample size of 296 participants was estimated based on an annual population of approximately 1.290 neurological patients treated at the hospital, assuming an expected prevalence of 50%, a 95% confidence level, and a 5% margin of error. Sample size calculation was performed using Epi Info software, version 7.2.5.0. A univariate analysis of the associations between categorical variables was performed using the chi-square test and Fisher's exact test. Given the extremely low number of positive cases, multivariate logistic regression was not performed due to model instability and the risk of overfitting. The statistical programs Epi Info 7 and Jamovi 2.7.13 were used for these analyses. All results with a p-value < 0.05, at a 95% confidence interval, are indicative of statistical significance. Declarations Conflict of interest The authors declare that they have no competing interests. Ethics approval and consent to participate This study was reviewed and approved by the Research Ethics Committee of the Center for Health Sciences, Federal University of Pernambuco (UFPE), under approval number CAAE: 83342724.1.0000.5208. Consent for publication Written informed consent was obtained from all participants, including consent for the anonymous publication of the data. Data availability The authors do not have permission to share participants’ data due to ethical and confidentiality restrictions. Materials availability Biological materials generated and analyzed during the current study are not publicly available due to ethical and confidentiality constraints but may be made available upon reasonable request to the corresponding author and subject to approval by the ethics committee. Code availability Not applicable. No custom code was generated or used in this study. Acknowledgements The authors thank Dra. Clélia Maria Ribeiro Franco, Head of the Neurology Outpatient Service at Hospital das Clínicas, UFPE, as well as the team of physicians and nurses for their daily support in the development of this research. The authors also acknowledge the financial support provided by the National Council for Scientific and Technological Development (CNPq) and the Coordination for the Improvement of Higher Education Personnel (CAPES). Author contribution Artur Fernando Soares da Silva: Conceptualization, Methodology, Investigation, Formal analysis, Project administration, Writing – original draft; Yan Charles da Silva Bastos: Conceptualization, Methodology, Project administration; Juliana Tiemi Oikawa: Methodology, Investigation; Ana Eliza Vargas Eskinazi Sant’Anna: Methodology, Investigation; Gabriel Galindo Cunha: Formal analysis, Data curation, Validation; Clarice Neuenschwander Lins de Morais: Methodology, Investigation; Elisa de Almeida Neves Azevedo: Methodology, Investigation; Maria Rosângela Cunha Duarte Côelho: Supervision, Resources, Funding acquisition, Project administration, Validation, Visualization, Writing – review & editing. References ALTIERI, Adrian, et al. “HTLV-1 and ATLL: Epidemiology, Oncogenesis, and Opportunities for Community-Informed Research in the United States”. Viruses , v. 17, n. 10, setembro de 2025, p. 1333. DOI.org (Crossref), https://doi.org/10.3390/v17101333. ARAÚJO, Abelardo; WEDEMANN, Diego. “HTLV-1 Associated Neurological Complex. What Is Hidden below the Water?” Aids Reviews , v. 21, n. 4, janeiro de 2020, p. 3403. DOI.org (Crossref), https://doi.org/10.24875/AIDSRev.19000108. ASSIS, Izabela Mendonca. et al. Análise dos níveis de carga proviral em portadores de HTLV-1 com diferentes condições de comprometimento neurológico. Research, Society and Development , v. 10, n. 3, p. e22310313264, 14 mar. 2021. BRASIL. Ministério da Saúde. Guia de Manejo Clínico da Infecção pelo HTLV. Brasília, DF: Ministério da Saúde, 2021. EUSEBIO-PONCE, Emiliana. et al. HTLV-1 infection: An emerging risk. Pathogenesis, epidemiology, diagnosis and associated diseases. Revista Espanola De Quimioterapia: Publicacion Oficial De La Sociedad Espanola De Quimioterapia, v. 32, n. 6, p. 485–496, dez. 2019. FERREIRA, Qesya Rodrigues, et al. “Neurological Aspects of HTLV-1 Infection: Symptoms in Apparently Asymptomatic Carriers”. Journal of NeuroVirology, v. 30, n. 4, agosto de 2024, p. 353–61. DOI.org (Crossref), https://doi.org/10.1007/s13365-024-01197-9. GASCON, Maria Rita, et al. “Memory impairment: an intermediate clinical syndrome symptom in HTLV-1-infected patients?” Arquivos de Neuro-Psiquiatria, v. 77, n. 6, junho de 2019, p. 429–35. DOI.org (Crossref), https://doi.org/10.1590/0004-282x20190062. HAZIOT, Michel E., et al. “Detection of Clinical and Neurological Signs in Apparently Asymptomatic HTLV-1 Infected Carriers: Association with High Proviral Load”. PLOS Neglected Tropical Diseases, organizado por Joseph Raymond Zunt, v. 13, n. 5, maio de 2019, p. e0006967. DOI.org (Crossref), https://doi.org/10.1371/journal.pntd.0006967. LEAL, Gabriela Rodrigues De Aguiar, et al. “Prevalence and First Detection of HTLV-2 in a Pregnant Woman in Rural Brazil”. Acta Tropica, v. 265, maio de 2025, p. 107632. DOI.org (Crossref), https://doi.org/10.1016/j.actatropica.2025.107632. LIMA, Victor Fernando da Silva, et al. Vírus Linfotrópicos de células T humanas (HTLV-1 e HTLV-2): revisão de literatura / Human T-cell lymphotropic viruses (HTLV-1 and HTLV-2): literature review. Brazilian Journal of Health Review, v. 4, n. 5, p. 20900–20923, 5 out. 2021. MARCUSSO, Rosa Maria Do Nascimento, et al. “HTLV-1-Associated Myelopathy (HAM) Incidence in Asymptomatic Carriers and Intermediate Syndrome (IS) Patients”. Pathogens, v. 13, n. 5, maio de 2024, p. 403. DOI.org (Crossref), https://doi.org/10.3390/pathogens13050403. ORGANIZAÇÃO MUNDIAL DA SAÚDE. Human T-lymphotropic virus type 1. Disponível em: . Acesso em: 14 abr. 2024. ROSADAS, Carolina, et al. Brazilian Protocol for Sexually Transmitted Infections 2020: human T-cell lymphotropic virus (HTLV) infection. Revista da Sociedade Brasileira de Medicina Tropical, v. 54, n. suppl 1, p. e2020605, 2021. ROSADAS, Carolina, et. al. Prevalência da infecção por HTLV-1/2 no Brasil. Boletim Epidemiológico, Secretaria de Vigilância em Saúde- Ministério da Saúde. 11, Vol. 51, n. 48, Nov. 2020. SAAB, Lea, et al. “HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP): Case Based Discussion of Risk Factors, Clinical, and Therapeutic Considerations”. Journal of the Neurological Sciences, v. 459, abril de 2024, p. 122973. DOI.org (Crossref), https://doi.org/10.1016/j.jns.2024.122973. SILVA, Bianca Lumi Inomata , et al. “Fibromyalgia in patients infected with HTLV-1 and HTLV-2”. Frontiers in Medicine, v. 11, agosto de 2024, p. 1419801. DOI.org (Crossref), https://doi.org/10.3389/fmed.2024.1419801. YAMAUCHI, Junji, et al. An update on human T-cell leukemia virus type I (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) focusing on clinical and laboratory biomarkers. Pharmacology & Therapeutics, v. 218, p. 107669, fev. 2021. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8842050","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":591695970,"identity":"f62195fb-3f49-40bb-abad-d104e00831c0","order_by":0,"name":"Artur Fernando Soares da Silva","email":"","orcid":"","institution":"Federal University of Pernambuco","correspondingAuthor":false,"prefix":"","firstName":"Artur","middleName":"Fernando Soares da","lastName":"Silva","suffix":""},{"id":591695971,"identity":"f770c72b-2575-4319-bac3-71a0f022c49a","order_by":1,"name":"Yan Charles da Silva Bastos","email":"","orcid":"","institution":"Federal University of Pernambuco","correspondingAuthor":false,"prefix":"","firstName":"Yan","middleName":"Charles da Silva","lastName":"Bastos","suffix":""},{"id":591695973,"identity":"5264c24d-372b-47ad-9087-7c63ae187fbb","order_by":2,"name":"Juliana Tiemi Oikawa","email":"","orcid":"","institution":"Federal University of Pernambuco","correspondingAuthor":false,"prefix":"","firstName":"Juliana","middleName":"Tiemi","lastName":"Oikawa","suffix":""},{"id":591695975,"identity":"11126aaa-07e2-4fad-8a7b-65e59b5ff89b","order_by":3,"name":"Ana Eliza Vargas Eskinazi Sant’Anna","email":"","orcid":"","institution":"Federal University of Pernambuco","correspondingAuthor":false,"prefix":"","firstName":"Ana","middleName":"Eliza Vargas Eskinazi","lastName":"Sant’Anna","suffix":""},{"id":591695983,"identity":"6ce2d5b7-8f78-4c09-af58-38ca04a2b7f7","order_by":4,"name":"Gabriel Galindo Cunha","email":"","orcid":"","institution":"Federal University of Pernambuco","correspondingAuthor":false,"prefix":"","firstName":"Gabriel","middleName":"Galindo","lastName":"Cunha","suffix":""},{"id":591695984,"identity":"28db26e8-dc7e-45e3-969e-a4917d9d78ac","order_by":5,"name":"Clarice Neuenschwander Lins de Morais","email":"","orcid":"","institution":"Oswaldo Cruz Foundation","correspondingAuthor":false,"prefix":"","firstName":"Clarice","middleName":"Neuenschwander Lins","lastName":"de Morais","suffix":""},{"id":591695986,"identity":"b8156b0e-9527-4055-9543-5ec5b2095b55","order_by":6,"name":"Elisa de Almeida Neves Azevedo","email":"","orcid":"","institution":"Oswaldo Cruz Foundation","correspondingAuthor":false,"prefix":"","firstName":"Elisa","middleName":"de Almeida Neves","lastName":"Azevedo","suffix":""},{"id":591695992,"identity":"a48745d4-1ab1-47ed-991e-e77094669d52","order_by":7,"name":"Maria Rosângela Cunha Duarte Coêlho","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYLCChw0MMmw8DIwPgGwePqK0JDYw8AC1MBuAtLARrQUI2SRAHIJazNsPH3yQuMOGh4/n8LPKrzl2MmwMzA8f3cCjReZMWrJB4pk0HjbeNrPbstuSgQ5jMzbOwaNFQoLHTCKx7TAPGz+D2W3JbcxALTxs0gS0mP+AaGH/Viy5rZ4oLWYMYC28PWaMH7cdJkILT1oy0GFAv/CcKZZm3Hach42ZkF/YDx/88LHNRk6+J33jx5/bqu352ZsfPsanBQUw84BJYpWDAOMPUlSPglEwCkbBiAEABYI8cymPfG0AAAAASUVORK5CYII=","orcid":"","institution":"Federal University of Pernambuco","correspondingAuthor":true,"prefix":"","firstName":"Maria","middleName":"Rosângela Cunha Duarte","lastName":"Coêlho","suffix":""}],"badges":[],"createdAt":"2026-02-10 14:23:36","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8842050/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8842050/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102964280,"identity":"4552d8b9-f452-4492-a063-2a853fa5a472","added_by":"auto","created_at":"2026-02-19 04:21:59","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":826645,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8842050/v1/b3528ac2-ae2e-4ef4-b1be-2abb7fe2bca0.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eHtlv-1 Infection in Patients With Neurological Manifestations in Northeast Brazil\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe Human T-lymphotropic Virus (HTLV) was the first oncogenic retrovirus identified in humans in 1977 and it is primarily transmitted through sexual contact, vertical transmission, and blood exposure (World Health Organization 2023). Among its types, HTLV-1 is the most significant, with an estimated 5 to 10\u0026nbsp;million infected individuals worldwide and between 800,000 to 2.5\u0026nbsp;million in Brazil, and it is associated with a broad spectrum of clinical manifestations, particularly neurological disorders. The main neurological condition related to HTLV-1 infection is HTLV-1\u0026ndash;associated myelopathy/tropical spastic paraparesis (HAM/TSP), a chronic, progressive inflammatory disease of the central nervous system (Lima et al. 2021). In addition to HAM/TSP, HTLV-1 infection may present with other neurological manifestations, including cognitive dysfunction, encephalopathies, neurogenic bladder, and myopathies, which may occur in isolation and vary according to the individual and duration of infection (Ferreira et al. 2024; Ara\u0026uacute;jo and Wedemann 2019).\u003c/p\u003e \u003cp\u003eGiven the slow and insidious progression of HAM/TSP, literature has described the presence of nonspecific neurological manifestations associated with HTLV-1 that precede the development of classical myelopathy. This set of alterations has been referred as Intermediate Syndrome (IS) and encompasses neurological manifestations that do not yet fulfill the diagnostic criteria for HAM/TSP but already indicate involvement of the central nervous system. Recognition of IS is essential for the early identification of HTLV-1\u0026ndash;associated neurological involvement and for the implementation of a more appropriate clinical approach (Marcusso et al. 2024).\u003c/p\u003e \u003cp\u003eIn patients presenting with neurological manifestations, HTLV-1 infection is of particular relevance due to its association with HAM/TSP and with neurological conditions compatible with Intermediate Syndrome, which are often underdiagnosed and exhibit a progressive course (Gascon et al. 2019; Yamauchi et al. 2021). However, the scarcity of regional epidemiological data and the underreporting of HTLV-1 infection hinder accurate estimates of its true magnitude, especially in endemic areas such as Northeast Brazil (Rosadas et al. 2020).\u003c/p\u003e \u003cp\u003eThe aim of this study was to estimate the prevalence of HTLV-1/2 infection and associated factors among patients with neurological disorders treated at a public hospital in the state of Pernambuco, Brazil, in 2025. Additionally, we sought to describe the sociodemographic, socioeconomic, behavioral, and clinical profiles of HTLV-positive patients, in order to support timely diagnosis, appropriate clinical management, and the strengthening of public health policies for screening and follow-up.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe study included 300 patients with neurological manifestations who underwent serological testing for HTLV-1/2 infection, with subsequent molecular confirmation. Of these, three tested positive for HTLV-1, resulting in an overall prevalence of 1.0% (3/300). The results of the univariate analysis of sociodemographic, socioeconomic, and behavioral variables of the overall study population, including all the positive cases, are summarized in Table 1.\u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003eDistribution of sociodemographic, socioeconomic, and behavioral variables of the study population.\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" valign=\"top\" style=\"width: 608px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSOCIODEMOGRAPHIC VARIABLES\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of positive cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of negative cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePlace of residence\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"4\" valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. Metropolitan Region of Recife (MRR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e165\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e55.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e50.01-61.18%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e2. Inland areas of the state\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e129\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e43.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e37.85\u0026ndash;48.99%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e3. Not reported\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e0.34-2.90%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex at birth\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.179\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1.Female\u003c/p\u003e\n \u003cp\u003e2.Male\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e185\u003c/p\u003e\n \u003cp\u003e112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e62.67%\u003c/p\u003e\n \u003cp\u003e37.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e57.07-67.95%\u003c/p\u003e\n \u003cp\u003e32.05-42.93%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge group (years)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.592\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. 18\u0026ndash;29 years\u003c/p\u003e\n \u003cp\u003e2. 30\u0026ndash;60 years\u003c/p\u003e\n \u003cp\u003e3. \u0026ge; 61 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003cp\u003e153\u003c/p\u003e\n \u003cp\u003e116\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e9.33%\u003c/p\u003e\n \u003cp\u003e51.33%\u003c/p\u003e\n \u003cp\u003e39.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e6.54-13.16%\u003c/p\u003e\n \u003cp\u003e45.70-56.94%\u003c/p\u003e\n \u003cp\u003e33.97-44.96%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEthnicity\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.282\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. White\u003c/p\u003e\n \u003cp\u003e2. Black\u003c/p\u003e\n \u003cp\u003e3. Mixed Race (Pardo)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e103\u003c/p\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003cp\u003e136\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e35.00%\u003c/p\u003e\n \u003cp\u003e19.67%\u003c/p\u003e\n \u003cp\u003e45.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e29.82-40.56%\u003c/p\u003e\n \u003cp\u003e15.56-24.54%\u003c/p\u003e\n \u003cp\u003e39.79-50.99%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMarital status\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. Single\u003c/p\u003e\n \u003cp\u003e2. Married / Stable union\u003c/p\u003e\n \u003cp\u003e3. Widowed / Divorced\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e105\u003c/p\u003e\n \u003cp\u003e145\u003c/p\u003e\n \u003cp\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e36.00%\u003c/p\u003e\n \u003cp\u003e48.33%\u003c/p\u003e\n \u003cp\u003e15.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e30.78-41.58%\u003c/p\u003e\n \u003cp\u003e42.74-53.97%\u003c/p\u003e\n \u003cp\u003e11.99-20.21%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" valign=\"top\" style=\"width: 608px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSOCIOECONOMIC VARIABLES\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of positive cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of negative cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEducation level\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.817\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. Illiterate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e9.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e6.81-13.54%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e2. Incomplete / complete Primary education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e133\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e45.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e39.47-50.66%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e3. Incomplete / complete secondary education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e104\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e34.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e29.51-40.22%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e4. Higher education / postgraduate studies\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e10.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e7.66-14.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIncome\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.822\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. No income\u003c/p\u003e\n \u003cp\u003e2. \u0026lt; one minimum wage\u003c/p\u003e\n \u003cp\u003e3. one minimum wage\u003c/p\u003e\n \u003cp\u003e4. two minimum wage\u003c/p\u003e\n \u003cp\u003e5. three or more minimum wage\u003c/p\u003e\n \u003cp\u003e6. Not reported\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003cp\u003e171\u003c/p\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e19.00%\u003c/p\u003e\n \u003cp\u003e8.67%\u003c/p\u003e\n \u003cp\u003e58.00%\u003c/p\u003e\n \u003cp\u003e6.33%\u003c/p\u003e\n \u003cp\u003e7.67%\u003c/p\u003e\n \u003cp\u003e0.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e14.96-23.82%\u003c/p\u003e\n \u003cp\u003e5.98-12.40%\u003c/p\u003e\n \u003cp\u003e52.35-63.45%\u003c/p\u003e\n \u003cp\u003e4.09-9.68%\u003c/p\u003e\n \u003cp\u003e5.16-11.24%\u003c/p\u003e\n \u003cp\u003e0.06-1.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" valign=\"top\" style=\"width: 608px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBEHAVIORAL VARIABLES\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of positive cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of negative cases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHistory of intravenous drug use\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.020\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. YES\u003c/p\u003e\n \u003cp\u003e2. NO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;1\u003c/p\u003e\n \u003cp\u003e296\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e0.67%\u003c/p\u003e\n \u003cp\u003e99.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e0.18-2.40%\u003c/p\u003e\n \u003cp\u003e97.60-99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge at sexual debut\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.305\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. No previous sexual activity\u003c/p\u003e\n \u003cp\u003e2. \u0026le; 18 years\u003c/p\u003e\n \u003cp\u003e3. \u0026ge; 19 years\u003c/p\u003e\n \u003cp\u003e4. Not reported\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003cp\u003e172\u003c/p\u003e\n \u003cp\u003e96\u003c/p\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e5.67%\u003c/p\u003e\n \u003cp\u003e57.66%\u003c/p\u003e\n \u003cp\u003e32.33%\u003c/p\u003e\n \u003cp\u003e4.34%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e3.34-8.91%\u003c/p\u003e\n \u003cp\u003e51.87-63.24%\u003c/p\u003e\n \u003cp\u003e27.07-37.93%\u003c/p\u003e\n \u003cp\u003e2.32-7.28%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCondom use\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. YES\u003c/p\u003e\n \u003cp\u003e2. NO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003cp\u003e190\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e32.15%\u003c/p\u003e\n \u003cp\u003e67.85%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e26.7-37.9%\u003c/p\u003e\n \u003cp\u003e62.1-73.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHistory of multiple sexual partners\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.346\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. YES\u003c/p\u003e\n \u003cp\u003e2. NO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003cp\u003e228\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e19.08%\u003c/p\u003e\n \u003cp\u003e80.91%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e14.7- 24.1%\u003c/p\u003e\n \u003cp\u003e75.9- 85.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHistory of blood transfusion\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.045\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. YES\u003c/p\u003e\n \u003cp\u003e2. NO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003cp\u003e260\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e13%\u003c/p\u003e\n \u003cp\u003e87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e9.66-17.28%\u003c/p\u003e\n \u003cp\u003e82.72-90.34%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFamily history of HTLV infection\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.020\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. YES\u003c/p\u003e\n \u003cp\u003e2. NO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003cp\u003e296\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e0.67%\u003c/p\u003e\n \u003cp\u003e99.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e0.18-2.40%\u003c/p\u003e\n \u003cp\u003e97.60-99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\" valign=\"top\" style=\"width: 546px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHistory of breastfeeding\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e0.250\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 190px;\"\u003e\n \u003cp\u003e1. YES\u003c/p\u003e\n \u003cp\u003e2. NO\u003c/p\u003e\n \u003cp\u003e3. \u0026nbsp; \u0026nbsp; Does not know / does not remember\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003cp\u003e1\u003cbr\u003e\u0026nbsp;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e228\u003c/p\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003cp\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 82px;\"\u003e\n \u003cp\u003e76.67%\u003c/p\u003e\n \u003cp\u003e7.67%\u003c/p\u003e\n \u003cp\u003e15.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e71.56-81.10%\u003c/p\u003e\n \u003cp\u003e5.16-11.24%\u003c/p\u003e\n \u003cp\u003e11.99-20.21%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 62px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eDetailed sociodemographic and socioeconomic characteristics of the three HTLV-1\u0026ndash;positive patients are presented in Table 2, while behavioral and clinical characteristics, including neurological manifestations and potential exposure factors, are summarized in Table 3.\u003cstrong\u003e\u003cbr\u003e\u0026nbsp;Table 2.\u0026nbsp;\u003c/strong\u003eSociodemographic and socioeconomic characteristics of neurological patients investigated for HTLV infection at a tertiary hospital in Northeast Brazil\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003ePacient\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eSex at birth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003eRace\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003eMarital Status\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eOccupation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 80px;\"\u003e\n \u003cp\u003eResidence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eIncome\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003eEducation\u003c/p\u003e\n \u003cp\u003eLevel\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eFeminine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e67y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003eWhite\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003eSingle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eRetired\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 80px;\"\u003e\n \u003cp\u003eRecife\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eBRL 1412\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003eIncomplete primary education\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eFeminine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e43y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003eBlack\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003eSingle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eRetired\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 80px;\"\u003e\n \u003cp\u003eCamaragibe\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eBRL 1412\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003eHigh school\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 78px;\"\u003e\n \u003cp\u003eFeminine\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e72y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003eWhite\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 63px;\"\u003e\n \u003cp\u003eSingle\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003eRetired\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 80px;\"\u003e\n \u003cp\u003eGaranhuns\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003eBRL 1412\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003eIncomplete primary education\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*BRL = Brazilian Real.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3.\u0026nbsp;\u003c/strong\u003eBehavioral and clinical characteristics of neurological patients investigated for HTLV infection at a tertiary hospital in Northeast Brazil\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePacient\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eInjecting drug use\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003eFirst Sexual\u003c/p\u003e\n \u003cp\u003eIntercourse\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003eMultiple sexual partners\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eUse of\u003c/p\u003e\n \u003cp\u003eCondoms\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eBlood transfusion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eBreastfed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 143px;\"\u003e\n \u003cp\u003eNeurological manifestation\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e14y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eYES, 2003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 143px;\"\u003e\n \u003cp\u003eParesthesia in the lower limbs; urinary incontinence.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e21y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 143px;\"\u003e\n \u003cp\u003eLower limb paralysis; neurogenic bladder.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 60px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003eNo history of sexual activity\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 61px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 67px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003eYES, 1988\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 69px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 143px;\"\u003e\n \u003cp\u003eVertigo; Syncope; Fibromyalgia; Lumbosciatica and Cervicalgia.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe prevalence of HTLV-1 infection of 1.0% observed among neurological patients in this study represents one of the first reports of HTLV-1 prevalence in this specific population in Brazil. This finding corroborates with results from studies conducted in other populations, such as pregnant women, among whom a prevalence of 0.49% has been reported by Leal et al. (2025), and Lima et al. (2021) in blood donors, for whom the national mean prevalence was estimated at 0.41%.\u003c/p\u003e \u003cp\u003eThe univariate analyses identified some statistically significant associations, however, these findings should be interpreted with caution, because there was no control for potential confounding factors. Additionally, due to the small number of positive cases, the multivariate analysis was not realized. Variables related to known HTLV transmission routes, such as injection drug use and a history of blood transfusion, showed statistical association with viral infection. Prior knowledge of HTLV, including the presence of a family history, was also statistically significant in the univariate analysis. These findings are consistent with risk factors discussed by Saab et al. (2024), with a case of HAM/TSP.\u003c/p\u003e \u003cp\u003eRegarding the sociodemographic and socioeconomic characteristics of HTLV-1\u0026ndash;positive participants (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), all three patients were female, aged between 43 and 72 years, in agreement with studies reporting a higher occurrence of HTLV-1 among women, especially older ones, possibly due to cumulative exposure risk over time (Rosadas et al., 2021). All the positive participants reported a monthly income equivalent to one minimum wage, and educational levels ranged from incomplete elementary education to completed secondary education, characteristics commonly observed in populations assisted by public health services and previously described in HTLV studies conducted in Brazil (Rosadas et al., 2020).\u003c/p\u003e \u003cp\u003eSexual transmission is recognized as one of the main routes of HTLV dissemination in Brazil, particularly in contexts involving unprotected sexual intercourse and multiple partners (Altieri et al., 2025; Eus\u0026eacute;bio-Ponce et al., 2019). In this study, two participants reported having initiated sexual activity at 14 and 21 years of age and not using condoms, additionally both were single, and one had a history of multiple sexual partners. It was not possible to establish an association between age at sexual debut and increased risk of HTLV infection, in contrast to findings from other studies that report higher risk associated with early sexual initiation (Leal et al., 2025).\u003c/p\u003e \u003cp\u003eRegarding blood-borne and vertical transmission routes of the three positive participants, one patient reported a history of injection drug use, a transmission route of HTLV previously described in the literature by Altieri et al. (2025). Two patients reported having received blood transfusions during surgical procedures in 2003 and 1988, respectively. In Brazil, routine screening of blood donors for HTLV has been mandatory since 1993 (Rosadas et al., 2021), and the Ministry of Health (2021) considers individuals who received transfusions prior to 1993 as a vulnerable population. In the case of the patient who received a transfusion in 1988, when HTLV testing was not mandatory, blood transfusion represents the most likely route of viral transmission. Two of the three HTLV-positive patients reported having been breastfed, among them, one had a family history of HTLV, with an infected mother. This finding is relevant, as it suggests that this was the route of infection for HTLV-1. Vertical transmission represents an important route of HTLV-1 transmission and occurs predominantly through breastfeeding according to Rosadas et al. (2020).\u003c/p\u003e \u003cp\u003eWith regard to the clinical profile and neurological manifestations of HTLV-positive participants described in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, two HTLV-1\u0026ndash;positive patients presented urinary symptoms combined with lower limb impairment, characteristic of HTLV infection, differing in severity and duration. Haziot et al. (2019) described that for a clinical condition to be considered Intermediate Syndrome (IS), the patient must present more than three signs found during a neurological evaluation, where the investigator is unaware of the patient's HTLV infection, the patient at an earlier disease stage reported paresthesia in the lower limbs, characterized by numbness, in addition to urinary incontinence, with symptom onset approximately two years prior, coinciding with the beginning of follow-up at the study site, but it was still under investigation regarding the presence of infection, being classified as an IS based on the results of this study. In contrast, the participant with more advanced disease, although attending her first neurology outpatient visit, had a prior diagnosis of HTLV infection and presented more severe neurological manifestations, including lower limb paralysis and a history of neurogenic bladder since 2012, characteristic of a defined HAM/TSP case described in the literature (Haziot et al. 2019). The third participant, despite reporting less typical neurological symptoms such as dizziness and nausea, also presented inflammatory manifestations, including lumbar and cervical pain, as well as musculoskeletal conditions such as fibromyalgia. This finding is consistent with the study by Silva et al. (2024), which described rheumatological alterations, including fibromyalgia, in patients infected with HTLV-1/2, and considering the absence of a previous diagnosis for HTLV infection, she can be also classified as IS according to the results of this study.\u003c/p\u003e \u003cp\u003eIn conclusion, the diversity of clinical presentations observed in this study, together with variability in disease severity, highlights the broad spectrum of neurological impairment associated with HTLV-1 infection. This investigation contributes to filling important information gaps and may support public health policies aimed at patients with neurological manifestations associated with HTLV-1 in Pernambuco, emphasizing the need for greater attention to neurological conditions that precede HAM/TSP and fall within the Intermediate Syndrome spectrum.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eAn analytical cross-sectional study was conducted among patients with neurological disorders followed at a tertiary university hospital in Northeast Brazil between 2024 and 2025. Participants provided written informed consent and completed structured interviews to collect sociodemographic, socioeconomic, behavioral, and clinical data. Peripheral blood samples were collected and analyzed at the Virology Laboratory of the Keizo Asami Institute (iLIKA-UFPE) using an enzyme-linked immunosorbent assay (ELISA) for screening of HTLV-1/2 infection with the commercial Diasorin Murex HTLV-1\u0026thinsp;+\u0026thinsp;2 kit. Samples with positive or indeterminate ELISA results underwent molecular detection using polymerase chain reaction (PCR) using the HiPurA Blood Genomic DNA Miniprep Purification kit.\u003c/p\u003e \u003cp\u003eThe minimum sample size of 296 participants was estimated based on an annual population of approximately 1.290 neurological patients treated at the hospital, assuming an expected prevalence of 50%, a 95% confidence level, and a 5% margin of error. Sample size calculation was performed using Epi Info software, version 7.2.5.0. A univariate analysis of the associations between categorical variables was performed using the chi-square test and Fisher's exact test. Given the extremely low number of positive cases, multivariate logistic regression was not performed due to model instability and the risk of overfitting. The statistical programs Epi Info 7 and Jamovi 2.7.13 were used for these analyses. All results with a p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05, at a 95% confidence interval, are indicative of statistical significance.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was reviewed and approved by the Research Ethics Committee of the Center for Health Sciences, Federal University of Pernambuco (UFPE), under approval number CAAE: 83342724.1.0000.5208.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003eWritten informed consent was obtained from all participants, including consent for the anonymous publication of the data.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003eThe authors do not have permission to share participants\u0026rsquo; data due to ethical and confidentiality restrictions.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials availability\u003c/strong\u003e\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003eBiological materials generated and analyzed during the current study are not publicly available due to ethical and confidentiality constraints but may be made available upon reasonable request to the corresponding author and subject to approval by the ethics committee.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCode availability\u003c/strong\u003e\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003e Not applicable. No custom code was generated or used in this study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003eThe authors thank Dra. Cl\u0026eacute;lia Maria Ribeiro Franco, Head of the Neurology Outpatient Service at Hospital das Cl\u0026iacute;nicas, UFPE, as well as the team of physicians and nurses for their daily support in the development of this research. The authors also acknowledge the financial support provided by the National Council for Scientific and Technological Development (CNPq) and the Coordination for the Improvement of Higher Education Personnel (CAPES).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contribution\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eArtur Fernando Soares da Silva: Conceptualization, Methodology, Investigation, Formal analysis, Project administration, Writing \u0026ndash; original draft; \u0026nbsp; Yan Charles da Silva Bastos: Conceptualization, Methodology, Project administration; Juliana Tiemi Oikawa: Methodology, Investigation; Ana Eliza Vargas Eskinazi Sant\u0026rsquo;Anna: Methodology, Investigation; \u0026nbsp; Gabriel Galindo Cunha: Formal analysis, Data curation, Validation; Clarice Neuenschwander Lins de Morais: Methodology, Investigation; Elisa de Almeida Neves Azevedo: Methodology, Investigation; Maria Ros\u0026acirc;ngela Cunha Duarte C\u0026ocirc;elho: Supervision, Resources, Funding acquisition, Project administration, Validation, Visualization, Writing \u0026ndash; review \u0026amp; editing.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eALTIERI, Adrian, et al. \u0026ldquo;HTLV-1 and ATLL: Epidemiology, Oncogenesis, and Opportunities for Community-Informed Research in the United States\u0026rdquo;. \u003cstrong\u003eViruses\u003c/strong\u003e, v. 17, n. 10, setembro de 2025, p. 1333. DOI.org (Crossref), https://doi.org/10.3390/v17101333.\u003c/li\u003e\n \u003cli\u003eARA\u0026Uacute;JO, Abelardo; WEDEMANN, Diego. \u0026ldquo;HTLV-1 Associated Neurological Complex. What Is Hidden below the Water?\u0026rdquo; \u003cstrong\u003eAids Reviews\u003c/strong\u003e, v. 21, n. 4, janeiro de 2020, p. 3403. DOI.org (Crossref), https://doi.org/10.24875/AIDSRev.19000108.\u003c/li\u003e\n \u003cli\u003eASSIS, Izabela Mendonca. et al. An\u0026aacute;lise dos n\u0026iacute;veis de carga proviral em portadores de HTLV-1 com diferentes condi\u0026ccedil;\u0026otilde;es de comprometimento neurol\u0026oacute;gico. \u003cstrong\u003eResearch, Society and Development\u003c/strong\u003e, v. 10, n. 3, p. e22310313264, 14 mar. 2021.\u003c/li\u003e\n \u003cli\u003eBRASIL. Minist\u0026eacute;rio da Sa\u0026uacute;de. Guia de Manejo Cl\u0026iacute;nico da Infec\u0026ccedil;\u0026atilde;o pelo HTLV. Bras\u0026iacute;lia, DF: Minist\u0026eacute;rio da Sa\u0026uacute;de, 2021.\u003c/li\u003e\n \u003cli\u003eEUSEBIO-PONCE, Emiliana. et al. HTLV-1 infection: An emerging risk. Pathogenesis, epidemiology, diagnosis and associated diseases. Revista Espanola De Quimioterapia: Publicacion Oficial De La Sociedad Espanola De Quimioterapia, v. 32, n. 6, p. 485\u0026ndash;496, dez. 2019.\u003c/li\u003e\n \u003cli\u003eFERREIRA, Qesya Rodrigues, et al. \u0026ldquo;Neurological Aspects of HTLV-1 Infection: Symptoms in Apparently Asymptomatic Carriers\u0026rdquo;. Journal of NeuroVirology, v. 30, n. 4, agosto de 2024, p. 353\u0026ndash;61. DOI.org (Crossref), https://doi.org/10.1007/s13365-024-01197-9.\u003c/li\u003e\n \u003cli\u003eGASCON, Maria Rita, et al. \u0026ldquo;Memory impairment: an intermediate clinical syndrome symptom in HTLV-1-infected patients?\u0026rdquo; Arquivos de Neuro-Psiquiatria, v. 77, n. 6, junho de 2019, p. 429\u0026ndash;35. DOI.org (Crossref), https://doi.org/10.1590/0004-282x20190062.\u003c/li\u003e\n \u003cli\u003eHAZIOT, Michel E., et al. \u0026ldquo;Detection of Clinical and Neurological Signs in Apparently Asymptomatic HTLV-1 Infected Carriers: Association with High Proviral Load\u0026rdquo;. PLOS Neglected Tropical Diseases, organizado por Joseph Raymond Zunt, v. 13, n. 5, maio de 2019, p. e0006967. DOI.org (Crossref), https://doi.org/10.1371/journal.pntd.0006967.\u003c/li\u003e\n \u003cli\u003eLEAL, Gabriela Rodrigues De Aguiar, et al. \u0026ldquo;Prevalence and First Detection of HTLV-2 in a Pregnant Woman in Rural Brazil\u0026rdquo;. Acta Tropica, v. 265, maio de 2025, p. 107632. DOI.org (Crossref), https://doi.org/10.1016/j.actatropica.2025.107632.\u003c/li\u003e\n \u003cli\u003eLIMA, Victor Fernando da Silva, et al. V\u0026iacute;rus Linfotr\u0026oacute;picos de c\u0026eacute;lulas T humanas (HTLV-1 e HTLV-2): revis\u0026atilde;o de literatura / Human T-cell lymphotropic viruses (HTLV-1 and HTLV-2): literature review. Brazilian Journal of Health Review, v. 4, n. 5, p. 20900\u0026ndash;20923, 5 out. 2021.\u003c/li\u003e\n \u003cli\u003eMARCUSSO, Rosa Maria Do Nascimento, et al. \u0026ldquo;HTLV-1-Associated Myelopathy (HAM) Incidence in Asymptomatic Carriers and Intermediate Syndrome (IS) Patients\u0026rdquo;. Pathogens, v. 13, n. 5, maio de 2024, p. 403. DOI.org (Crossref), https://doi.org/10.3390/pathogens13050403.\u003c/li\u003e\n \u003cli\u003eORGANIZA\u0026Ccedil;\u0026Atilde;O MUNDIAL DA SA\u0026Uacute;DE. Human T-lymphotropic virus type 1. Dispon\u0026iacute;vel em: \u0026lt;https://www.who.int/news-room/fact-sheets/detail/human-t-lymphotropic-virus-type-1\u0026gt;. Acesso em: 14 abr. 2024.\u003c/li\u003e\n \u003cli\u003eROSADAS, Carolina, et al. Brazilian Protocol for Sexually Transmitted Infections 2020: human T-cell lymphotropic virus (HTLV) infection. Revista da Sociedade Brasileira de Medicina Tropical, v. 54, n. suppl 1, p. e2020605, 2021.\u003c/li\u003e\n \u003cli\u003eROSADAS, Carolina, et. al. Preval\u0026ecirc;ncia da infec\u0026ccedil;\u0026atilde;o por HTLV-1/2 no Brasil. Boletim Epidemiol\u0026oacute;gico, Secretaria de Vigil\u0026acirc;ncia em Sa\u0026uacute;de- Minist\u0026eacute;rio da Sa\u0026uacute;de. 11, Vol. 51, n. 48, Nov. 2020.\u003c/li\u003e\n \u003cli\u003eSAAB, Lea, et al. \u0026ldquo;HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP): Case Based Discussion of Risk Factors, Clinical, and Therapeutic Considerations\u0026rdquo;. Journal of the Neurological Sciences, v. 459, abril de 2024, p. 122973. DOI.org (Crossref), https://doi.org/10.1016/j.jns.2024.122973.\u003c/li\u003e\n \u003cli\u003eSILVA, Bianca Lumi Inomata , et al. \u0026ldquo;Fibromyalgia in patients infected with HTLV-1 and HTLV-2\u0026rdquo;. Frontiers in Medicine, v. 11, agosto de 2024, p. 1419801. DOI.org (Crossref), https://doi.org/10.3389/fmed.2024.1419801.\u003c/li\u003e\n \u003cli\u003eYAMAUCHI, Junji, et al. An update on human T-cell leukemia virus type I (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) focusing on clinical and laboratory biomarkers. Pharmacology \u0026amp; Therapeutics, v. 218, p. 107669, fev. 2021.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-neurovirology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"njiv","sideBox":"Learn more about [Journal of NeuroVirology](http://link.springer.com/journal/13365)","snPcode":"13365","submissionUrl":"https://submission.nature.com/new-submission/13365/3","title":"Journal of NeuroVirology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Human T-lymphotropic virus type 1, Neurological Disorders, HTLV-1–associated myelopathy, Epidemiology","lastPublishedDoi":"10.21203/rs.3.rs-8842050/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8842050/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eHuman T-lymphotropic virus (HTLV) infection is associated with a broad spectrum of neurological manifestations, including conditions that may precede the development of HTLV-1\u0026ndash;associated myelopathy/tropical spastic paraparesis. This analytical cross-sectional study aimed to estimate the prevalence of HTLV-1 infection and describe associated sociodemographic, socioeconomic, behavioral, and clinical characteristics among patients with neurological disorders followed at a tertiary public hospital in Northeast Brazil between 2024 and 2025. A total of 300 patients underwent serological screening using an immunoenzymatic assay with a commercial kit (Murex HTLV-I\u0026thinsp;+\u0026thinsp;II-Diasorin UK), and molecular confirmation by polymerase chain reaction for positive or indeterminate samples using a commercial kit (HiPurA Blood Genomic DNA Miniprep Purification). Three patients tested positive for HTLV-1 infection, resulting in an overall prevalence of 1.0%. All individuals who tested positive for HTLV-1 were women aged 43 to 72 years, with low educational level and income. Univariate analyses identified significant associations with injection drug use, history of blood transfusion, and family history of HTLV-1/2.\u003c/p\u003e \u003cp\u003eClinically, HTLV-1 positive patients presented heterogeneous neurological manifestations, ranging from urinary dysfunction and lower limb sensory and motor impairment to musculoskeletal and inflammatory symptoms, compatible with early or intermediate neurological syndrome. These findings highlight the presence of HTLV-1 infection among neurological patients and reinforce the importance of targeted screening in this population. Early identification of HTLV-1 may contribute to improved clinical management and support public health strategies aimed at preventing disease progression and reducing underdiagnosis in endemic regions.\u003c/p\u003e","manuscriptTitle":"Htlv-1 Infection in Patients With Neurological Manifestations in Northeast Brazil","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-18 15:48:46","doi":"10.21203/rs.3.rs-8842050/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-06T19:07:12+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-01T20:03:16+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-24T15:01:52+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"188964946645413046949340449405655110537","date":"2026-02-15T17:23:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"278775359150517886608891175756155895541","date":"2026-02-13T15:17:31+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-12T21:29:04+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-12T00:03:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-12T00:03:46+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of NeuroVirology","date":"2026-02-10T13:17:26+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-neurovirology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"njiv","sideBox":"Learn more about [Journal of NeuroVirology](http://link.springer.com/journal/13365)","snPcode":"13365","submissionUrl":"https://submission.nature.com/new-submission/13365/3","title":"Journal of NeuroVirology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"2452da11-2c3f-4c33-adc8-e7a57dbd9e2d","owner":[],"postedDate":"February 18th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-15T15:39:16+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-18 15:48:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8842050","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8842050","identity":"rs-8842050","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}