title: Prevalence and molecular characterization of human T cell leukemia virus type 2 in a group of intravenous drug users coinfected with HIV type 1 in Portugal.
abstract: Human T cell lymphotropic virus type 2 infections can be found in the large urban areas of the United States and Europe, where Spain and Italy are the most affected countries. The population most affected by the epidemic is characterized by high-risk behavior groups, mainly the sharing of needles between intravenous drug users (IDUs) with contaminated cellular blood products. It is also described that HTLV-2 infection appears as a coinfection with HIV-1. We have selected samples corresponding to 583 IDUs infected with HIV and screened for the presence of HTLV-1/2 antibodies. We have performed the molecular characterization of HTLV-2 in three confirmed positive cases on the basis of the long terminal repeat region. We can observe the Portuguese sequences (PortHl, PortNn, and PortVs) in the HTLV-2b cluster, grouping with the Spanish sequences, showing close phylogenetic relatedness. We may assume that HTLV-2 infection was introduced in Portugal from Spain. These results update previous reports that mentioned Portugal as being free of HTLV- 2 infections, and allow the identification of the subtype that is present, giving a first-hand description of the prevalence of HTLV-2 infection in a particular high-risk behavior group and justifying the importance of epidemiological surveillance in order to prevent dissemination of the infection.
authors.affiliation: Laboratório de Referência da SIDA/Centro de Virologia, Instituto Nacional de Saúde, P-1649-016 Lisbon, Portugal.
authors.forename: Ana Filipa
authors.initials: AF
authors.lastname: Silva
authors.forename: Catarina
authors.initials: C
authors.lastname: Almeida
authors.forename: Helena Cortes
authors.initials: HC
authors.lastname: Martins
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Coutinho
authors.forename: Emília
authors.initials: E
authors.lastname: Leitão
authors.forename: Rui
authors.initials: R
authors.lastname: Silva
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Paixão
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Pádua
mesh_terms: D001483:Base Sequence; D005260:Female; D015658:HIV Infections / Q000150:complications*; D015497:HIV-1; D015481:HTLV-I Antibodies / Q000097:blood; D015482:HTLV-II Antibodies / Q000097:blood; D015491:HTLV-II Infections / Q000150:complications / Q000453:epidemiology / Q000821:virology*; D015367:Human T-lymphotropic virus 2 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011174:Portugal / Q000453:epidemiology; D012367:RNA, Viral / Q000235:genetics; D016415:Sequence Alignment; D015819:Substance Abuse, Intravenous / Q000150:complications*; D020079:Terminal Repeat Sequences / Q000235:genetics
chemical_list: D015481:HTLV-I Antibodies; D015482:HTLV-II Antibodies; D012367:RNA, Viral