Moderada endemicidade da infecção pelo vírus linfotrópico-T humano na região metropolitana de Belém, Pará, Brasil / Moderate endemicity of the human T-lymphotropic virus infection in the metropolitan region of Belém, Pará, Brazil

RESUMO: Introdução: A disseminação da infecção pelo vírus linfotrópico-T humano (HTLV) em famílias da área metropolitana de Belém, Pará, Brasil, e a ausência de estudos na população em geral requisitam investigações que esclareçam melhor a sua prevalência na região. Metodologia: Foi realizada pesquisa de anticorpos anti-HTLV-1/HTLV-2 em indivíduos adultos transeuntes de logradouros públicos de Belém, entre novembro de 2014 e novembro de 2015. A infecção foi confirmada por pesquisa de DNA proviral e foi realizada avaliação clínica e investigação intrafamiliar dos infectados. Resultados: Dos 1.059 indivíduos investigados, 21 (2,0%) apresentaram amostras sororeagentes, 15 (1,4%) confirmados para HTLV-1, 5 (0,5%) para HTLV-2 e o DNA proviral foi indetectável em 1 caso. A média de idade dos infectados (57,2) foi maior que a dos não infectados (46,2) (p = 0,0010). A infecção aumentou com a idade e se destacou nos indivíduos com renda familiar menor ou igual a um salário mínimo. A transmissão intrafamiliar parece ter ocorrido em todas as famílias investigadas. Dentre os portadores de HTLV-1, 30% (3/10) já apresentavam algum sintoma relacionado à infecção. Discussão: O aumento da infecção de acordo com a idade pode ocorrer por soroconversão tardia de infecção pré-adquirida ou pelo risco cumulativo de novas infecções, sobretudo em mulheres. Conclusão: A infecção por HTLV demonstrou moderada prevalência na população estudada, com predomínio do HTLV-1. Essa mostrou-se associada à baixa renda e ao aumento da idade das mulheres. Também apresentou disseminação intrafamiliar e negligência no diagnóstico das doenças associadas.

ABSTRACT: Introduction: The spread of the HTLV infection in families living in the metropolitan area of Belém, Pará, Brazil, and the lack of studies in the general population requires studies to better understand its prevalence in the region. Methods: An anti-HTLV-1/HTLV-2 antibodies test was carried out on random adults in public places in Belém between November 2014 and November 2015. A proviral DNA test detected if the person was infected, and then a clinical evaluation and an intrafamilial investigation were carried out. Results: Of the 1059 individuals being investigated, 21 (2.0%) had seroreagent samples, 15 (1.4%) had HTLV-1, 5 (0.5%) had HTLV-2, and proviral DNA was undetectable in one case. The mean age of the infected people (57.2) was higher than that of those that were uninfected (46.2) (p = 0.0010). The prevalence of infection increased with age, especially in individuals with a family income equal to or less than a minimum wage. Intrafamilial transmission seems to have occurred in all of the families being studied. Among the patients with HTLV-1, 30% (3/10) already had some symptom related to the infection. Discussion: The increase in prevalence rates according to age may be due to late seroconversion of a previously acquired infection, or the cumulative risk of new infections, especially in women. Conclusion: There was a moderate prevalence of the HTLV infection among adult individuals from the metropolitan area of Belém, with a predominance of HTLV-1. This infection was associated with low income and increasingly older women. It also presented intrafamily spread and negligence in the diagnosis of associated diseases.

Comparative performances of serologic and molecular assays for detecting human T lymphotropic virus type 1 and type 2 (HTLV-1 and HTLV-2) in patients infected with human immunodeficiency virus type 1 (HIV-1)

ABSTRACT The present study evaluated several techniques currently available (commercial kits and in-house assays) for diagnosing human T lymphotropic viruses types 1 and 2 in two groups of patients enrolled at HIV/AIDS specialized care services in São Paulo: Group 1 (G1), n = 1608, 1237 male/371 female, median age 44.3 years old, majority using highly active antiretroviral therapy (HAART); G2, n = 1383, 930 male/453 female, median age of 35.6 years old, majority HAART naïve. Enzyme immunoassays [(EIA) Murex and Gold ELISA] were employed for human T lymphotropic viruses types 1 and 2 screening; Western blotting (WB), INNO-LIA (LIA), real-time PCR pol (qPCR), and nested-PCR-RFLP (tax) were used to confirm infection. Samples were considered human T lymphotropic viruses types 1 and 2 positive when there was reactivity using at least one of the four confirmatory assays. By serological screening, 127/2991 samples were positive or borderline, and human T lymphotropic virus infection was confirmed in 108 samples (three EIA-borderline): 56 human T lymphotropic virus type 1 [G1 (27) + G2 (29)]; 45 human T lymphotropic virus type 2 [G1 (21) + G2 (24)]; one human T lymphotropic virus type 1 + human T lymphotropic virus type 2 (G2); six human T lymphotropic virus [G1 (2) + G2 (4)]. Although there were differences in group characteristics, human T lymphotropic viruses types 1 and 2 prevalence was similar [3.1% (G1) and 4.2% (G2), p = 0.113]. The overall sensitivities of LIA, WB, qPCR, and PCR-RFLP were 97.2%, 82.4%, 68.9%, and 68.4%, respectively, with some differences among groups, likely due to the stage of human T lymphotropic virus infection and/or HAART duration. Indeterminate immunoblotting results were detected in G2, possibly due to the seroconversion period. Negative results in molecular assays could be explained by the use of HAART, the occurrence of defective provirus and/or the low circulating proviral load. In conclusion, when determining the human T lymphotropic virus infection, the findings highlight that there is a need to consider the blood samples with borderline results in screening assays. Of all the tested assays, LIA was the assay of choice for detecting human T lymphotropic virus type 1 and human T lymphotropic virus type 2 in human immunodeficiency virus type 1-infected patients.

Seroprevalencia del virus linfotrópico humano de tipos I y II en donantes del Banco de Sangre de la Fundación Valle del Lili, Cali, Colombia, 2008-2014 / Seroprevalence of human T-lymphotropic virus in blood bank donors at Fundación Valle del Lili, Cali, Colombia, 2008-2014

Introducción. El virus linfotrópico humano (HTLV) de tipos I y II es un retrovirus prevalente en la Costa Pacífica colombiana que puede transmitirse por transfusiones de sangre. En el 2014 se reglamentó la tamización para bancos de sangre con el fin de reducir la transmisión por medio de la donación. La información sobre la seroprevalencia del virus en el suroccidente colombiano es limitada. Objetivo. Determinar la seroprevalencia, el comportamiento a lo largo del tiempo de los resultados reactivos antes y después de la introducción del inmunoensayo Western blot y la concomitancia del HTLV con otros marcadores de infección en donantes de un banco de sangre de Cali, Colombia. Materiales y métodos. Se hizo un estudio trasversal de 77.117 donantes del Banco de Sangre de la Fundación Valle del Lili mediante el análisis de los registros de donantes con prueba reactiva para anticuerpos IgG anti HTLV I-II entre enero de 2008 y diciembre de 2014. Resultados. La seroprevalencia acumulada fue de 0,24 %. Los resultados reactivos fueron más frecuentes en mujeres (61 %) y la mediana de edad fue de 37 años. La seroprevalencia en los años previos a la introducción del Western blot fue de 0,13, 0,19, 0,31 y 0,32 % (2008-2012), y posteriormente fue de 0,18, 0,08 y 0,07 % (2012-2014). La reacción positiva concomitante con otros marcadores de infección fue de 11 %: sífilis (57 %), HIV (19 %), hepatitis B (14 %) y hepatitis C (9 %). La mayor seroprevalencia (0,38 %) se registró en el 2012. Conclusión. Se encontró una alta prevalencia de pruebas reactivas para el HTLV I-II en comparación con otros estudios. Los resultados de este estudio son un punto de partida para el desarrollo de estudios poblacionales.

Introduction: Human lymphotropic virus (HTLV I/II) is a retrovirus that is prevalent across the Colombian Pacific coast, and is potentially transmissible by transfusion. Blood bank screening has been regulated since 2004, in order to reduce transmission of HTLV I/II through donation. Information on the seroprevalence of the virus in southwestern Colombia is limited. Objective: To determine the seroprevalence and the behavior of reactivity to HTLV I/II before and after the introduction of Western blot, and the comorbidity of HTLV and other infectious markers in donors from a blood bank in Cali, Colombia. Materials and methods: We conducted a cross-sectional study of 77,117 blood bank donors from the Fundación Valle del Lili by analyzing records of donors who had been tested with the reactive test for anti-HTLV I-II antibodies (IgG) between January, 2008, and December, 2014. Results: The cumulative seroprevalence during the study period was 0.24% (186/77,119). Reactivity was more common in women (61%), and the median age was 37 years (IQR: 24-48). The seroprevalence in the years before the introduction of Western blot was 0.13%, 0.19%, 0.31%, 0.32% and 0.18% (2008-2012), and thereafter it was 0.08% and 0.07% (2012-2014). Concomitant reactivity with other infectious markers was 11%: syphilis (57%), followed by HIV (19%), hepatitis B (14%) and hepatitis C (9%). The highest seroprevalence (0.38%) was reported in 2012. Conclusion: We found a high prevalence of reactivity to HTLV I-II compared to that reported in other studies. The results of this study are a starting point for the development of population studies.

Geographic distribution of human T-lymphotropic virus types 1 and 2 among mothers of newborns tested during neonatal screening, Minas Gerais, Brazil / Distribución geográfica del virus linfotrópico de células T humanas tipos 1 y 2 en madres de recién nacidos estudiados en el tamizaje neonatal en Minas Gerais, Brasil

OBJECTIVE: To evaluate the geographic distribution of human T-lymphotropic virus types 1 and 2 (HTLV-1/2) in the State of Minas Gerais, Brazil, in puerperal women whose newborns were tested for HTLV-1/2 during neonatal screening, and to overlap seropositivity with social and economic status determinants. METHODS: During September-November 2007, the dry-blood samples taken from newborns on filter paper for routine screening were also tested for maternal IgG anti-HTLV-1/2 antibodies. For reactive samples, the mothers of the newborns had blood drawn to test for these viruses. RESULTS: The study analyzed 55 293 specimens taken from newborns. Of these, 52 (9.4 per 10 000) were reactive and 42 mothers (7.6 per 10 000) were confirmed with HTLV-1/2 infection. HTLV-1/2 geographic distribution was heterogeneous, with a tendency to be higher in the North and North-East parts of Minas Gerais. The highest rates of seropositivity were observed in Vale do Mucuri (55.9 per 10 000) and in Jequitinhonha (16.0 per 10 000), overlapping with the State's worst social and economic indicators. CONCLUSIONS: To our knowledge this was the first time that neonatal screening for HTLV-1/2 was performed in Brazil. This model could be used in other areas with high HTLV-1/2 prevalence rates. The detection of carrier mothers can enable intervention measures, such as providing infant formula to newborns, to be implemented expeditiously to reduce vertical transmission.

OBJETIVOS: Evaluar la distribución geográfica del virus linfotrópico de células T humanas tipos 1 y 2 (HTLV-1/2) en el estado de Minas Gerais (Brasil), en mujeres puérperas en cuyos recién nacidos se analizó la presencia del HTLV-1/2 durante las pruebas neonatales de detección sistemática, y superponer la seropositividad con determinantes del estado socioeconómico. MÉTODOS: Entre septiembre y noviembre de 2007, en las muestras de sangre seca extraída a los recién nacidos en papel de filtro para un tamizaje sistemático, se analizaron también los anticuerpos maternos de tipo IgG anti-HTLV-1/2. En el caso de las muestras reactivas, se extrajo la sangre de las madres de los recién nacidos para realizar pruebas de detección de estos virus. RESULTADOS: En el estudio se analizaron 55 293 muestras extraídas de los recién nacidos. De estas, 52 (9,4 por 10 000) fueron reactivas y en 42 madres (7,6 por 10 000) se confirmó la infección por el HTLV-1/2. La distribución geográfica del HTLV-1/2 fue heterogénea, con una tendencia a ser mayor en el norte y el noreste de Minas Gerais. Las tasas más elevadas de seropositividad se observaron en Vale do Mucuri (55,9 por 10 000) y en Jequitinhonha (16,0 por 10 000), superponiéndose con los peores indicadores socioeconómicos del estado. CONCLUSIONES: Esta fue la primera vez que se realizó un tamizaje neonatal para el HTLV-1/2 en Brasil. Este modelo podría usarse en otras regiones con tasas de prevalencia altas del HTLV-1/2. La detección de las madres portadoras puede permitir la aplicación rápida de medidas de intervención, como por ejemplo, el suministro de leche maternizada a los recién nacidos, a fin de reducir la transmisión vertical.

Prevalência, fatores de risco e caracterização genética dos vírus linfotrópico de células T humana tipo 1 e 2 em pacientes infectados pelo vírus da imunodeficiência humana tipo 1 nas Cidades de Ribeirão Preto e São Paulo / Prevalence, risk factors and genetic characterization of human T-cell lymphotropic virus types 1 and 2 in patients infected with human immunodeficiency virus type 1 in the cities of Ribeirão Preto and São Paulo

O objetivo deste estudo foi definir a prevalência dos vírus linfotrópico de células T humana tipo 1 e 2 em pacientes positivos para o vírus da imunodeficiência humana tipo 1 no Estado de São Paulo, Brasil. Avaliamos 319 indivíduos atendidos em clínicas de Ribeirão Preto e Capital. Os pacientes foram entrevistados e testados sorologicamente. Foram seqüenciadas as regiões tax e long terminal repeat para diferenciação e determinação do subtipo. A soroprevalência geral foi de 7,5 por cento (24/319) e esteve associada somente com uso de drogas injetáveis e ao vírus da hepatite tipo C (p<0, 001). O genoma viral foi detectado em 13 das 24 amostras, sendo 12 caracterizadas como HTLV-2 subtipo 2c e uma como 1a. Nossos dados mostraram que o uso de drogas injetáveis é um importante fator de risco para a transmissão de HTLV-2 em populações infectadas pelo vírus da imunodeficiência humana tipo 1.

The aim of this study was to define the prevalence of human T cell lymphotropic virus types 1 and 2 in patients who were positive for human immunodeficiency virus type 1 in the State of São Paulo, Brazil. We evaluated 319 individuals infected with HIV type 1 who were attended at specialized clinics in two cities (Ribeirão Preto and São Paulo). The patients were interviewed and tested for antibodies against HTLV types 1 and 2 (Orthoâ HTLV-1/HTLV-2 Ab-Capture enzyme immunoassay). Direct DNA sequencing of polymerase chain reaction products from the tax region of HTLV type 2 and the long terminal repeat region of HTLV types 1 and 2 were performed to differentiate and determine the subtypes. The overall prevalence of anti-HTLV type 1 and 2 antibodies was 7.5 percent (24/319; 95 percent CI: 5.2-11.5). HTLV type 1 and 2 infection was associated with a history of injected drug use and with antibodies for hepatitis C virus (p < 0.001), but not with age (p = 0.2), sex (p = 0.9), sexual behavior or serological markers for sexually transmitted diseases (anti-Treponema pallidum, anti-human herpesvirus type 8 or anti-hepatitis B virus antibodies) (p > 0.05). HTLV DNA was detected in 13 out of 24 samples, of which 12 were characterized as HTLV subtype 2c and one as HTLV subtype 1a. Among the 12 HTLV type 2 samples, seven were from injected drug users, thus indicating that this route is an important risk factor for HTLV type 2 transmission among our population infected with HIV type 1.

Prevalência da infecção pelo vírus linfotrópico humano de células T - HTLV-1/2 entre puérperas de Cuiabá, Estado de Mato Grosso, 2006 / Prevalence of human T-cell lymphotropic virus (HTLV-1/2) infection among puerperae in Cuiabá, Mato Grosso, 2006

A prevalência da infecção pelo vírus linfotrópico humano de células T em puérperas do Estado de Mato Grosso, no Brasil, não é conhecida. Neste estudo transversal definiu-se a prevalência da infecção em puérperas atendidas em três maternidades públicas de Cuiabá (MT). De abril a setembro de 2006, 3.831 partos foram realizados e 2.965 puérperas foram submetidas aos testes sorológicos para o HTLV-1/2 (Enzyme Linked Immuno Sorbent Assay - ELISA e Western Blot). A idade média das mulheres participantes foi de 23,9 anos. A prevalência da infecção pelo HTLV-1/2 foi de 0,2 por cento, semelhante à observada na população geral de vários centros desenvolvidos do país. Esse achado de baixa prevalência sugere que ainda não é justificada a introdução de intervenção de saúde pública para a população de gestantes de nosso meio, visando à redução da transmissão vertical do HTLV-1/2.

The prevalence of human T-cell lymphotropic virus (HTLV-1/2) infection among puerperae in the State of Mato Grosso, Brazil, is unknown. Through this cross-sectional study, the prevalence of HTLV-1/2 infection among puerperae attended at three public maternity hospitals in Cuiabá, State of Mato Grosso, was defined. Between April and September 2006, 3,831 deliveries took place and 2,965 puerperae underwent serological tests for HTLV-1/2: enzyme-linked immunosorbent assay (ELISA) and western blot. The mean age of the women studied was 23.9 years. The prevalence of HTLV-1/2 was 0.2 percent, i.e. similar to the prevalence observed in the general population of many developed centers in Brazil. This finding of low prevalence suggests that there is still no justification for introducing public health interventions for the population of pregnant women in our setting, to reduce the vertical transmission of HTLV-1/2.

Confirming the presence of HTLV-1 infection and the absence of HTLV-2 in blood donors from Arequipa, Peru / Confirmação da presença de infecção por HTLV-1 e ausência de infecção por HTLV-2 em doadores de sangue de Arequipa, Peru

Epidemiological studies conducted in Peru disclosed HTLV-1 to be prevalent in different ethnic groups, and found HTLV-2 in some Amazonian Indians and in men who have sex with men. No data concerning HTLV-1/2 infection in blood donors from Arequipa, a highlands region in southern Peru, is available. We searched for the presence of HTLV-1 and HTLV-2 antibodies in 2,732 serum samples obtained from blood donors from this geographic area. HTLV-1/2-specific antibodies were detected using an enzyme-linked immunosorbent assay (ELISA) and were confirmed by Western blot (WB). Reactive sera had their blood bags discarded from donation, and the demographic characteristics of the donors were analyzed. Thirty-five sera (1.2 percent) were HTLV seroreactive by ELISA, and 25 were confirmed HTLV-1-positive by WB. One serum disclosed HTLV-positivity, and the remaining nine serum samples showed indeterminate results by WB; three of which had an HTLV-1 indeterminate Gag profile. The median age of HTLV-positive individuals was 34.6 years; 27 were male and eight were female. All individuals were from southern Peru: 27 from Arequipa, five from Puno, and three from Cuzco. HTLV co-positivity with hepatitis B (five sera) and syphilis (one serum) were detected. Previous transfusion and tattooing were observed in two and one individuals, respectively. No serum was positive for HTLV/HIV co-infection. This study confirmed, for the first time, HTLV-1 infection and the absence of HTLV-2 infection in blood donors from Arequipa, Peru and suggests vertical transmission as the major route of HTLV-1 transmission and acquisition in this geographic region.

Estudos epidemiológicos conduzidos no Peru apontam a infecção por HTLV-1 como prevalente em diferentes grupos étnicos e por HTLV-2 restrita a alguns índios da região Amazônica e a homens que fazem sexo com homens. Não existem dados sobre a infecção por HTLV-1/2 em doadores de sangue de Arequipa, região montanhosa do sul do Peru. Portanto, o presente estudo pesquisou anticorpos anti-HTLV-1 e HTLV-2 em 2.732 doadores de sangue desta região geográfica. Foram utilizados na triagem sorológica os testes imunoenzimáticos (ELISA) e para confirmação dos resultados o Western Blot (WB). Soros reagentes no ELISA tiveram suas bolsas de sangue descartadas. Os resultados obtidos foram analisados de acordo com características demográficas dos indivíduos. Trinta e cinco soros (1,2 por cento) resultaram HTLV-1/2 reagentes no ELISA, 25 confirmaram infecção por HTLV-1 no WB. Um soro resultou HTLV positivo e os nove soros restantes resultaram em padrão indeterminado no WB: três com perfil HTLV-1 Gag indeterminado. A média de idade dos indivíduos HTLV positivos foi de 34,6 anos; 27 do gênero masculino e oito do gênero feminino. Todos eram da região sul do país: 27 de Arequipa, cinco de Puno e três de Cuzco. Foi detectada co-positividade HTLV com hepatite B (cinco soros) e sífilis (um soro). Nenhum soro resultou positivo para a co-infecção HIV/HTLV. Havia dois indivíduos com transfusão prévia e um com tatuagem. Este trabalho confirma pela primeira vez infecção por HTLV-1 e ausência de infecção por HTLV-2 em doadores de sangue de Arequipa, sul do Peru e sugere que a transmissão vertical seja a principal via de transmissão/aquisição de HTLV-1 nesta região geográfica.

Infecção pelo HTLV 1/2: atuação no pré-natal como estratégia de controle da doença no Estado de Mato Grosso do Sul / HTLV 1/2 infection: prenatal performance as a disease control strategy in State of Mato Grosso do Sul

Neste estudo, foi estimada a prevalência da infecção pelo HTLV 1/2 em gestantes no Estado de Mato Grosso do Sul, por meio das técnicas ELISA, Western Blot e PCR, em amostras de sangue obtidas por punção venosa periférica. Foram examinadas 116.689 gestantes, sendo diagnosticadas 153 infectadas pelo HTLV 1/2, com prevalência de 0,13 por cento. Deste total, 133 (86,9 por cento) eram do tipo 1 e 20 (11,1 por cento) do tipo 2. Das 153 gestantes, 73,2 por cento eram negras, pardas ou índias, cerca de 90 por cento tinham atividades domésticas e 75,8 por cento (116/153) tinham 7 anos ou menos de escolaridade. As 153 gestantes tiveram 172 gestações, durante o período do estudo, sendo que 164 tiveram acompanhamento. Das gestações acompanhadas, 6,7 por cento (11/164) evoluíram para aborto, 26,8 por cento (41/153) gestantes relataram abortos anteriores, sendo que 31,7 por cento (13/41) apresentaram mais de dois abortos. Co-morbidades foram detectadas em 17 por cento (26/153) sendo 3,3 por cento (5/153) com HIV (p<0,000002). Os autores enfatizam a importância da identificação das gestantes infectadas pelo HTLV1/2 na estratégia de controle e prevenção da doença.

In this study, the prevalence of HTLV 1/2 infection among pregnant women in the State of Mato Grosso do Sul was estimated by means of the ELISA, Western Blot and PCR techniques, in blood samples collected by peripheral venous puncture. 116,689 pregnant women were examined and 153 were diagnosed as presenting HTLV 1/2 infection, with prevalence of 0.13 percent. Among these 153 pregnant women, 133 (86.9 percent) had type 1 and 20 (11.1 percent) had type 2; 73.2 percent were black, brown or indigenous; about 90 percent performed domestic activities; and 75.8 percent (116/153) had been to school for seven years or less. The 153 pregnant women had 172 pregnancies during the study period and 164 pregnancies were followed. Out of pregnancies that were followed, 6.7 percent (11/164) evolved to abortion, 26.8 percent (41/153) reported previous abortions and 31.7 percent (13/41) had had more than two abortions. Comorbidities were found in 17 percent (26/153), among whom 3.3 percent (5/153) had HIV (p<0.000002). The authors emphasize the importance of identifying pregnant women with HTLV 1/2 infection, as a strategy for disease control and prevention.

Performances of HTLV serological tests in diagnosing HTLV infection in high-risk population of São Paulo, Brazil

Testing problems in diagnosing human T-lymphotropic virus (HTLV) infection, mostly HTLV-II, have been documented in HIV/AIDS patients. Since December 1998, the Immunology Department of Instituto Adolfo Lutz (IAL) offers HTLV-I/II serology to Public Health Units that attend HTLV high-risk individuals. Two thousand, three hundred and twelve serum samples: 1,393 from AIDS Reference Centers (Group I), and 919 from HTLV out-patient clinics (Group II) were sent to IAL for HTLV-I/II antibodies detection. The majority of them were screened by two enzyme immunoassays (EIAs), and confirmed by Western Blot (WB 2.4, Genelabs). Seven different EIA kits were employed during the period, and according to WB results, the best performance was obtained by EIAs that contain HTLV-I and HTLV-II viral lysates and rgp21 as antigens. Neither 1st and 2nd, nor 3rd generation EIA kits were 100 percent sensitive in detecting truly HTLV-I/II reactive samples. HTLV-I and HTLV-II prevalence rates of 3.3 percent and 2.5 percent were detected in Group I, and of 9.6 percent and 3.6 percent in Group II, respectively. High percentages of HTLV-seroindeterminate WB sera were detected in both Groups. The algorithm testing to be employed in HTLV high-risk population from São Paulo, Brazil, needs the use of two EIA kits of different formats and compounds as screening, and because of high seroindeterminate WB, may be another confirmatory assay.

Problemas nos testes diagnósticos de infecção pelos vírus linfotrópicos de células T humanas (HTLV), principalmente HTLV-II, têm sido observados em pacientes com HIV/Aids. Desde Dezembro de 1998, a Seção de Imunologia do Instituto Adolfo Lutz (IAL) oferece a sorologia para HTLV-I/II para Serviços de Saúde Pública que atendem populações consideradas de risco para esta infecção. Duas mil trezentas e doze amostras de soro: 1.393 de Centros de Referência em Aids (Grupo I) e 919 de Clínicas de Especialidade em HTLV (Grupo II) foram encaminhadas para o IAL para a pesquisa de anticorpos anti-HTLV-I/II. A maioria delas foram testadas por dois ensaios imunoenzimáticos (EIAs) e confirmadas por Western Blot (WB 2.4, Genelabs). Sete kits diferentes de EIAs foram empregados durante o período e de acordo com os resultados do WB a melhor performance foi obtida com os EIAs que continham lisado viral dos HTLV-I e -II e a rgp21 como antígenos. Nenhum kit de EIA de 1ª, 2ª ou 3ª geração foi 100 por cento sensível para detectar todas as amostras verdadeiramente HTLV-I/II reagentes. A prevalência de HTLV-I e HTLV-II, respectivamente, foi de 3,3 por cento e 2,5 por cento no Grupo I e de 9,6 por cento e 3,6 por cento no Grupo II. Em ambos os Grupos, foram detectadas altas percentagens de soros com padrão indeterminado no WB. O algoritmo de testes sorológicos para ser usado em população de alto risco para HTLV de São Paulo, Brasil, necessita de dois kits EIAs de princípios e composição diferentes para a triagem sorológica e, pelo elevado número de WB indeterminado, talvez de um outro teste confirmatório.

Difficulties in the diagnosis of HTLV-2 infection in HIV/AIDS patients from Brazil: comparative performances of serologic and molecular assays, and detection of HTLV-2b subtype

The current diagnosis of human T-lymphotropic virus type-2 (HTLV-2) infection is based on the search of specific antibodies; nevertheless, several studies conducted in Brazil pointed deficiencies of the commercially available kits in detecting HTLV-2, mostly in HIV/AIDS patients. This study searched for the presence of HTLV-1 and -2 in 758 HIV/AIDS patients from Londrina, Paraná, Brazil. Serum samples were screened for HTLV-1/2 antibodies using two EIA kits (Vironostika and Murex), and confirmed by WB (HTLV Blot 2.4, Genelabs). The results obtained by EIA disclosed 49 (6.5 percent) reactive sera: 43 positive by both EIA kits, and six with discordant results. WB confirmed HTLV-1 infection in seven samples (0.9 percent) and HTLV-2 in 21 sera (2.8 percent). Negative and indeterminate results were detected in four (0.5 percent) and 16 (2.1 percent) sera, respectively. Blood from 47 out of 49 HTLV seroreactive patients were collected and analyzed for the presence of env, LTR and tax genomic segments of HTLVs by PCR. PCR confirmed six cases of HTLV-1 and 37 cases of HTLV-2 infection (14 out of 16 that were found to be WB indeterminate). Restriction analysis of the env PCR products of HTLV-2 disclosed 36 isolates of HTLV-2a/c subtype, and one of HTLV-2b subtype. These results emphasize the need of improving serologic tests for detecting truly HTLV-2 infected patients from Brazil, and confirm the presence of HTLV-2b subtype in the South of this country.

O diagnóstico de infecção por HTLV-2 se baseia na pesquisa de anticorpos específicos, entretanto, vários estudos conduzidos no Brasil têm apontado falhas nos kits sorológicos disponíveis no mercado em detectar HTLV-2, principalmente nos pacientes com HIV/aids. Este trabalho avaliou a presença de infecção por HTLV-1 e -2 em 758 pacientes HIV/aids de Londrina, Paraná, Brasil. Amostras de soro foram analisadas quanto à presença de anticorpos anti-HTLV-1/2 por dois kits de EIA (Vironostika e Murex) e confirmados por WB (HTLV Blot 2.4, Genelabs). Os resultados obtidos pelos testes sorológicos mostraram 49 (6,5 por cento) soros reagentes: 43 positivos para ambos os kits e seis com resultados discordantes. O WB confirmou infecção por HTLV-1 em sete soros (0,9 por cento) e HTLV-2 em 21 soros (2,8 por cento). Resultados negativos e indeterminados foram detectados, respectivamente, em quatro (0,5 por cento) e 16 (2,1 por cento) soros. Amostras de sangue de 47 dos 49 pacientes com sorologia reagente foram avaliadas quanto à presença de segmentos do genoma dos HTLVs (env, LTR e tax), usando a técnica de PCR. As PCRs confirmaram seis casos de infecção por HTLV-1 e 37 casos por HTLV-2 (14 dos 16 cuja sorologia resultou WB indeterminada). A subtipagem de HTLV-2 por análise de restrição enzimática de produtos da PCR env mostrou 36 isolados de subtipo HTLV-2a/c e um HTLV-2b. Esses resultados reforçam a necessidade de melhorar o diagnóstico de infecção por HTLV-2 no Brasil e confirmam a presença do subtipo HTLV-2b na região sul do país.

Is seroprevalence of HTLV-I/II among blood donors in India relevant?

Human T-cell lymphotropic virus type I/II (HTLV-I/II) is associated with certain hematologic and neurologic disorders. Seroprevalence studies demonstrate that the distribution of HTLV-I/II is heterogeneous worldwide and not specific to one region. Because blood is one of the major routes of transmission of the virus, blood banks of several countries routinely screen all blood donations for HTLV-I/II. The aim of the present study was to assess the seroprevalence rate of HTLV-I/II antibodies among Indian blood donors and to confirm the positive rates by polymerase chain reaction (PCR). Between Jan 2004 to May 2005, consecutive blood samples of 10,000 blood donors were collected at the blood bank of Armed Forces Medical College, Pune. The samples were screened for HTLV-I/II by enzyme-linked immunosorbent assay (ELISA) method. Screening resulted in 18 (0.18%) positive samples, of which 14 (77.8%) samples were also positive by PCR. The prevalence of HTLV-I/II carriers in India seems to be negligible and is not a major public health hazard. Hence, routine screening of Indian blood donors for antibody to HTLV-I/II is not warranted due to its low prevalence in India.

Detección de anticuerpos contra los virus linfotrópicos de células T Tipo I, II, HTLV I, II, como medida de seguridad sanguínea en donantes de sangre en Costa Rica, mayo del 2002 a diciembre del 2004 / Detection of antibodies against viruses linfotropicos T cell type I, II, HTLV I, II, as a security measure blood in blood donors in Costa Rica, May 2002 December 2004

Los Virus Linfotrópicos Humanos tipo I y II, HTLV I, II, fueron los primeros retrovirus descritos y aislados en 1980. Tienen distribución mundial y son endémicos en el sur de Japón, el Caribe, algunos países del Sur y Centro América, Africa occidental y algunas otras poblaciones. Aunque la mayoría de infectados permanecen asintomáticos por largos períodos, el HTLV I es el agente causal de la leucemia linfoma de células T del adulto, LTA, y de la Paraparesia Espástica Tropical, PET o mielopatía asociada, MAH. El HTLV II se identificó inicialmente en un paciente con leucemia peluda de células T, pero se requieren más estudios para establecer la relación entre ambos. Dos de las principales vías de transmisión son la transfusión sanguínea o por compartir agujas de individuos infectados en drogadicción. Para controlar la transmisión de la infección en Costa Rica, se inició en el año 2002 un proyecto de la Sección de Laboratorios Clínicos de la CCSS, para la tamización de anticuerpos contra estos retrovirus a todos los donantes de sangre, fecha histórica para nuestro país por ser el primero en tener una cobertura del 100 por ciento de los donantes en América Latina...

During 1980, Human T lymphotropic virus (HTLV-I /II) were the first retrovirus identified and isolated.The geographic distribution of the virus is global, with endemic regions like south Japan, the Caribbean islands, western Africa, some South and Central America countries and other specific populations.Most infected patients remain without symptoms for long periods of time but association with human disease has been demonstrated. HTLV-II has been linked to adult T-cell leukemia/lymphoma (ATL/ATLL) and is also the causative agent of a neurological disorder termed HTLV-II associated Myelopathy/ttropical Spastic Parapesis.HTLV-II was first identified in a patient with hairy-cell leukemia, however better studies are needed to establish the relation between both. HTLV can be transmitted by blood transfusion and sharing of needles and syringes. During 2002, Costa Rica became the first Latin American country with 100% coverage of blood donors. In this year, the Sección de Laboratorios Clínicos de la CCSS began as a project the screening for antibodies against HTLV in order to avoid transmission through this route. Of 106958 blood donors, 582 (0,54%) were initially reactive by enzyme-immunolinked assay (EELISA), 272 (46,7%) were reactive in duplicated with the same ELISA and they were analyzed by a second ELISA and 232 were confirmed with an "in-house "Western Blot (WB).. Those represent the 0.25% of the initial population. Twenty seven samples (0.03%) confirmed positives and 136 (0.13%) were indeterminate. A commercial WB was performed with 13 of these positive samples, 7 were HTLV-II, 5 were HTLV-III and 1 was an indeterminate pattern...

Human T - cell lymphotropic virus type II in Guaraní Indians, Southern Brazil

O vírus linfotrópico de células T-humanas do tipo II (HTLV-II) é identificado em muitos grupos de ameríndios. No Brasil, tem sido encontrado em indivíduos da população urbana, bem como em índios oriundos da região Amazônica. Os Índios Guaraní, do Sul do país, foram investigados para infecção por HTLV-I/II. Três indivíduos, oriundos de uma amostra de 52 índios, demonstraram sororeatividade para HTLV-II (ensaio imunoenzimático e Western blot). Este estudo preliminar foi o primeiro a identificar a presença de infecção por HTLV-II em ameríndios do Sul do Brasil.

Molecular characterization of human T-cell lymphotropic virus coinfecting human immunodeficiency virus 1 infected patients in the Amazon region of Brazil

The present work evaluated the epidemiology of human immunodeficiency virus 1/human T-cell lymphotropic virus (HIV-1/HTLV) coinfection in patients living in Belém (state of Pará) and Macapá (state of Amapá), two cities located in the Amazon region of Brazil. A total of 169 blood samples were collected. The sera were tested by enzyme-linked immunosorbent assay to determine the presence of antibodies anti-HTLV-1/2. Confirmation of infection and discrimination of HTLV types and subtypes was performed using a nested polymerase chain reaction targeting the pX and 5' LTR regions, followed by restriction fragment length polymorphism and sequencing analysis. The presence of anti-HTLV1/2 was detected in six patients from Belém. The amplification of the pX region followed by RFLP analysis, demonstrated the presence of HTLV-1 and HTLV-2 infections among two and four patients, respectively. Sequencing HTLV-1 5' LTR indicated that the virus is a member of the Cosmopolitan Group, Transcontinental subgroup. HTLV-2 strains isolated revealed a molecular profile of subtype HTLV-2c. These results are a reflex of the epidemiological features of HIV-1/HTLV-1/2 coinfection in the North region of Brazil, which is distinct from other Brazilian regions, as reported by previous studies.

Determinación de la presencia de anticuerpos anti-HTLV I/II en sujetos con riesgo para la infección / Presence of antibodies against HTLV I/II in a high-risk populations for infection

La presencia de virus linfotrópicos de células T humanas, tipo I y II, en determinadas zonas de Venezuela; nos llevaron a realizar este estudio clínico de tipo transversal, para conocer la frecuencia de infectados en grupos de alto riesgo, del estado Mérida. A los 44 individuos del estudio, 31 promiscuos sexuales y usuarios de drogas y 13 con neoplasias hematológicas, se les determinó la presencia de anticuerpos contra estos retrovirus, por ELISA y western blot. Ninguno de estos sujetos en estudio fue seropositivo. A pesar de que esta región esta muy cercana a focos de infección en Brasil, La Guajira Colombiana y en el Estado Zulia; nosotros, al menos en los sujetos estudiados, no encontramos evidencia serológica de infección por estos patógenos

Prevalence of human T-lymphotropic virus type I and type II antibody among blood donors in Eastern Saudi Arabia

Human T-cell leukemia/lymphoma virus type I and type II [HTLV-I/II] infections can be transfusion associated, leading to tropical paraparesis, myelopathy and other neurological disorders. The aim of this study is to circumvent the risk of transmission through blood transfusion and to describe the prevalence of HTLV-I/II antibody among blood donors of Al-Hasa region and the cost effectiveness of screening blood donors. The study was conducted at the Department of Laboratory and Blood Bank, King Fahad Hospital, Al-Hofuf, Al-Hasa, Kingdom of Saudi Arabia during the period of 1997 to 2003. A total of 47426 blood donors were screened for HTLV-I/II antibody by enzyme-linked immunosorbent assay test, during the 7 years of study period. The positive samples were confirmed by western blot analysis. Overall, HTLV-I antibody positivity [confirmed by western blot] was 3/47426 [0.006%]. Out of 3 donors positive for HTLV-I antibody during 1997 to 1998, 2 were expatriates [Indian] and one was native Saudi donor. Human T-cell leukemia/lymphoma virus type I antibody positivity among the native Saudi donors was 1/47426 [0.002%] [2/100000 blood donors]. None of the donor were positive for HTLV-II antibody. During the last 5 consecutive years of the study period [1999-2003], none of the donor was positive for HTLV-I/II antibody. Al-Hasa region is non-endemic for HTLV-I/II virus infections. Screening of native Saudi blood donors for these viruses does not appear to be cost effective

Sero-epidemiological study on the human T-cell leukaemia virus type I/II infection in the east coastal areas of Fujian province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the seroprevalence of human T-cell leukaemia virus type I/II (HTLV-I/II) infection in adult population in the east coastal areas of Fujian and to explore the possible risk factors of HTLV-I/II.</p><p><b>METHODS</b>A total number of 3259 blood samples from drug users, sexually transmitted disease (STD) patients, prostitutes and blood donors for serologic assays during 1999 to 2002, were collected. All samples were screened for HTLV-I/II antibody, using enzyme linked immunosorbent assay (ELISA) kits. All of the positive samples were confirmed by western blot (WB) kits. Statistical analysis was done by Epi software, and chi(2) test by Fisher's exact test. P value < 0.05 was considered statistically significant.</p><p><b>RESULTS</b>The overall seroprevalence rate of HTLV-I/II in healthy populations was 0.06% including, 0.32% in drug users, 0.58% in STD patients and prostitutes respectively. HTLV-II had not been found. The seropositive rates for HTLV-I in STD patients and prostitutes were significantly higher than the findings among healthy populations (P < 0.05). There were no different seroprevalence rates between drug users and healthy populations (P > 0.05). No significant changes in HTLV-I prevalence rates were found in the different age groups as well as in Fuzhou and Linde cities (P > 0.05).</p><p><b>CONCLUSION</b>The result suggested that in the east coastal areas of Fujian province, HTLV-I was the main prevalent virus. The seroprevalence of HTLV-I was very low, with no HTLV-II. Neither age nor gender seemed to be HTLV-I risk factor in the east coastal areas of Fujian province, but the increase of exposure to sex might be one.</p>

Evaluation of surrogate markers for human immunodeficiency virus infection among blood donors at the blood bank of "Hospital Universitário Regional Norte do Paraná", Londrina, PR, Brazil

This study evaluated the usefulness of the anti-HBc, hepatitis C virus antibodies (anti-HCV), human T cell lymphotropic virus I and II antibodies (anti-HTLV I/II), serologic tests for syphilis, and surface antigen of hepatitis B virus (HBsAg) as surrogate markers for the risk for HIV infection in 80,284 serum samples from blood donors from the Blood Bank of "Hospital Universitário Regional Norte do Paraná", Londrina, Paraná State, Brazil, analyzed from July 1994 to April 2001. Among 39 blood donors with positive serology for HIV, 12 (30.8 percent) were anti-HBc positive, 10 (25.6 percent) for anti-HCV, 1 (2.6 percent) for anti-HTLV I/I, 1 (2.6 percent) was positive for syphilis, and 1 (2.6 percent) for HBsAg. Among the donors with negative serology for HIV, these markers were detected in 8,407 (10.5 percent), 441 (0.5 percent), 189 (0.2 percent), 464 (0.6 percent), and 473 (0.6 percent) samples, respectively. The difference was statistically significant (p < 0.001) for anti-HBc and anti-HCV. Although the predictive positive value for these surrogate markers were low for HIV infection, the results confirmed the anti-HBc and anti-HCV as useful surrogate markers for HIV infection thus reinforcing the maintenance of them in the screening for blood donors contributing to the prevention of the small number of cases in which HIV is still transmitted by transfusion

Prevalence of antibodies to human T-lymphotropic viruses types I and II among healthy blood donors

To assess the prevalence of human T-cell lymphotropic virus type I and type II antibodies in blood donors donating blood for various reasons in a University hospital and to compare the results with other reports from the Kingdom of Saudi Arabia [KSA], and elsewhere. A 7-year retrospective review of blood bank records for results of serological tests at the King Fahd Hospital of the University, Al-Khobar, KSA, from January 1995 to December 2001 was conducted. The study included review of blood donor questionnaire cards as well as extraction of any other relevant information. The results showed that the total number of blood donor units drawn during the 7- year period was 23493 units. A total of 50 units were found repeatedly reactive by enzyme immunoassay screening test [0.2%]. Only 12 [0.05%] were confirmed reactive by western blot test and 4 were found to be indeterminate. Nine [0.04%] of the confirmed samples were from Saudi nationals. All 3 non-Saudi confirmed reactive donors were Indian nationals, while the 4 indeterminate cases, 2 were Saudis and 2 were Egyptians. A statistical estimate of the maximal risk of finding a positive donor in this donor population subgroup is in the order of 0.05%. The number of Saudi blood donors during this study was 16434 [80.3%] and non-Saudi donors was 4027 [19.7%]. Based on these results it is shown that the prevalence of this virus is still low among blood donors in the Eastern region of Kingdom of Saudi Arabia

Ausencia de circulación de los virus HTLV-I/II en donantes de sangre de las provincias de Santa Fe y Santiago del Estero / Absence of HTLV-I/II virus circulation in blood donors from the provinces of Santa Fe and Santiago del Estero

In the present study, we evaluated the seroprevalence of HTLV-I/II infection among the blood donors in Santa Fe and Santiago del Estero provinces. A total of 1327 serum samples from blood donors from Rafaela blood bank of Santa Fe province and 3382 serum samples from blood donors from Dr Edgar Bouzon blood bank of Santiago del Estero province were studied. The antibody screening was done by particle agglutination assay (PA) (SERODIA, Fujirebio Inc., Tokyo, Japan) or by enzyme immuno assay (EIA) (Abbott HTLV-I/HTLV-II EIA, Abbott, Germany). The "in house" indirect immunofluorescence assay (IFA) and Western blot (Bioblot HTLV Biokit, Barcelona, Spain) were used as confirmatory assays. All the samples resulted negative for specific antibodies against HTLV-I/II. These results suggest that HTLV-I/II are not circulating in low risk populations in these provinces or that the prevalences of infection would be lower than that reported by blood banks in other provinces of Argentina.