title: High prevalence of HTLV-1 infection among Japanese immigrants in non-endemic area of Brazil.
abstract: BACKGROUND
  Human T-lymphotropic virus type 1 (HTLV-1) has worldwide distribution and is considered endemic in many world regions, including southwestern Japan and Brazil. Japanese immigrants and their descendants have a high risk of acquiring this infection due to intense population exchange between Brazil and Japan.
  
  
  OBJECTIVE
  This cross-sectional study aimed to estimate the prevalence of HTLV, analyze the main risk factors associated with this infection, identify the main circulating types and subtypes of HTLV in Japanese immigrants and descendants living in Campo Grande-MS (Middle-West Brazil), as well as analyze the phylogenetic relationship among isolates of HTLV.
  
  
  METHODS
  A total of 219 individuals were interviewed and submitted to blood collection. All collected blood samples were submitted for detection of anti-HTLV-1/2 using the immunoassay ELISA and confirmed by immunoblot method. The proviral DNA of the 14 samples HTLV- 1 positive were genotyped by nucleotide sequencing.
  
  
  RESULTS
  The overall prevalence of HTLV-1 was 6.8% (IC 95%: 3,5-10,2). Descriptive analysis of behavioral risk factors showed statistical association between HTLV-1 and age greater than or equal to 45 years. The proviral DNA of HTLV-1 was detected in all HTLV-1 positive samples. Of these, 14 were sequenced and classified as Cosmopolitan subtype, and 50% (7/14) belonged to subgroup A (transcontinental) and 50% (7/14) to the subgroup B (Japanese).
  
  
  CONCLUSIONS
  The high prevalence of HTLV-1 found evidence of the importance of early diagnosis and counseling of individuals infected with HTLV-1 for the control and prevention of the spread of this infection among Japanese immigrants and their descendants in Central Brazil.
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Larissa M
authors.initials: LM
authors.lastname: Bandeira
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Silvia N O
authors.initials: SN
authors.lastname: Uehara
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Marcel A
authors.initials: MA
authors.lastname: Asato
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Gabriela S
authors.initials: GS
authors.lastname: Aguena
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Cristiane M
authors.initials: CM
authors.lastname: Maedo
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Nikolas H
authors.initials: NH
authors.lastname: Benites
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Marco A M
authors.initials: MA
authors.lastname: Puga
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Grazielli R
authors.initials: GR
authors.lastname: Rezende
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Carolina M
authors.initials: CM
authors.lastname: Finotti
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Gabriela A
authors.initials: GA
authors.lastname: Cesar
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Tayana S O
authors.initials: TS
authors.lastname: Tanaka
authors.affiliation: Central Public Health Laboratory, LACEN/MS, Camp Grande, Mato Grosso do Sul, Brazil.
authors.forename: Vivianne O L
authors.initials: VO
authors.lastname: Castro
authors.affiliation: Laboratory of Molecular Genetics of Microorganisms and Oswaldo Cruz Institute, Rio de Janeiro, Brazil.
authors.forename: Koko
authors.initials: K
authors.lastname: Otsuki
authors.affiliation: Laboratory of Molecular Genetics of Microorganisms and Oswaldo Cruz Institute, Rio de Janeiro, Brazil.
authors.forename: Ana C P
authors.initials: AC
authors.lastname: Vicente
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Fernandes
authors.affiliation: Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil; Oswaldo Cruz Foundation, Campo Grande, Mato Grosso do Sul, Brazil.
authors.forename: Ana R C
authors.initials: AR
authors.lastname: Motta-Castro
mesh_terms: D000328:Adult; D000367:Age Factors; D000914:Antibodies, Viral / Q000097:blood; D001483:Base Sequence; D001938:Brazil / Q000453:epidemiology; D003430:Cross-Sectional Studies; D054242:Emigrants and Immigrants / Q000706:statistics & numerical data*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015490:HTLV-I Infections / Q000453:epidemiology*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000276:immunology; D006801:Humans; D015151:Immunoblotting; D007564:Japan / Q000208:ethnology; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D015995:Prevalence; D017422:Sequence Analysis, DNA
chemical_list: D000914:Antibodies, Viral