Assuntos
Síndrome da Imunodeficiência Adquirida/transmissão , Infecções por HIV/transmissão , Infecções Sexualmente Transmissíveis/transmissão , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Métodos Epidemiológicos , Feminino , Ouro , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Masculino , Mineração , Prevalência , Fatores de Risco , Educação Sexual , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Venezuela/epidemiologiaRESUMO
The peripheral blood of 41 Yaruro and Guahibo Indians from Venezuela was examined for HTLV antibodies and DNA. Twenty-five samples (61%) were found to be infected with HTLV-IIB. The sensitivities of the serologic and DNA polymerase chain reaction (PCR) analyses were 80% and 96%, respectively. Epidemiologic studies supported both sexual and perinatal transmission of the virus. Sequence analyses of the HTLV-IIB strains from these Indians indicate that they are unique relative to HTLV-II detected in other groups of humans. HTLV-IIB-G2 isolated from a Guahibo Indian is the most divergent HTLV-IIB strain relative to the prototype HTLV-II NRA.
Assuntos
Infecções por HTLV-II/etnologia , Vírus Linfotrópico T Tipo 2 Humano/genética , Indígenas Sul-Americanos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Sequência de Bases , Cricetinae , Transmissão de Doença Infecciosa , Infecções por HTLV-II/genética , Infecções por HTLV-II/transmissão , Vírus Linfotrópico T Tipo 2 Humano/classificação , Humanos , Transmissão Vertical de Doenças Infecciosas , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Homologia de Sequência do Ácido Nucleico , Estudos Soroepidemiológicos , Venezuela/epidemiologiaRESUMO
Sera from 166 Guahibo Indians (55% of the population) living in southwest Venezuela were screened by enzyme-linked immunoassay for antibodies to human T-cell lymphotropic virus (HTLV) I and II. Positive samples were confirmed by immunofluorescence and Western blot. Forty-one Guahibos (24.8%) were found to be seropositive. Polymerase chain reaction (PCR) analysis of proviral DNA in mononuclear cell lysates revealed the virus to be HTLV-II. Prevalence increased with age, and sexual contact with HTLV-II-seropositive partners was identified as a risk factor for infection. PCR amplification of a region of the pol gene, utilizing the primer pair SK110/SK111, with subsequent digestion of the 140-base-pair amplification products with HinfI and MseI restriction enzymes, showed an HTLV-II subtype-b restriction pattern in all cases. These data suggest that the substrain infecting this Guahibo community belongs to the b subtype, the most frequent among Paleo-Amerindian populations.
Assuntos
Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Adolescente , Adulto , Fatores Etários , Idoso , Western Blotting , Criança , Pré-Escolar , DNA Viral/análise , Feminino , Genes pol , Infecções por HTLV-II/genética , Infecções por HTLV-II/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 2 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Humanos , Indígenas Sul-Americanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Comportamento Sexual , Venezuela/epidemiologiaRESUMO
The clinical and public health importance of CD4+ T lymphocytopenia without human immunodeficiency virus infection is still unclear. We describe herein two new human immunodeficiency virus-negative patients with low numbers of peripheral CD4+ T cells and opportunistic infections (cerebral toxoplasmosis and tuberculosis plus extrapulmonary histoplasmosis). The low numbers of CD4+ CD29+ memory cells, the high percentage of gamma delta T-cell receptor cells, and the recovery of CD4+ cells after treatment were remarkable.
Assuntos
Subpopulações de Linfócitos T/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/imunologia , Adulto , Antígenos CD4/imunologia , Linfócitos T CD4-Positivos/imunologia , Feminino , Humanos , Integrina beta1/imunologia , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , T-Linfocitopenia Idiopática CD4-Positiva/terapiaRESUMO
We describe for the first time the presence of human T lymphotropic virus type II (HTLV-II) infection in Venezuela, among the Pume Amerindians living in the southern plains of the country. Antibodies to HTLV-II antigens were assessed by enzyme immunoassays (Elisa), Western blot, radioimmuno-precipitation, and immunofluorescence; titration studies against HTLV-I- and HTLV-II-infected cell lines were very useful in the differentiation of HTLV-I and HTLV-II antibodies. The HTLV-II general prevalence was 5%; however, there is a striking difference in prevalence between the truly isolated villages (0%) when compared to those living along the riverside and thus in contact with outsiders (9%). Preliminary evidence suggests sexual contact as the main source of transmission. These findings might suggest that HTLV-II in Venezuela originated through contact with outsiders rather than ancient infection related to the origins of the Pume.
Assuntos
Infecções por HTLV-II/etnologia , Indígenas Sul-Americanos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Anticorpos Anti-HTLV-I/sangue , Anticorpos Anti-HTLV-II/sangue , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Ensaio de Radioimunoprecipitação , Venezuela/epidemiologiaRESUMO
A study of the immunopathogenic characteristics of HIV infection was begun in 1984 at the National Reference Center on Clinical Immunology (CNRIC) in Caracas, Venezuela, on 240 individuals with a variety of clinical manifestations. The most important findings were depletion of the CD4 cells in HIV-infected individuals, including asymptomatic carriers; significant reduction of the CD3-, CD16+ large granular lymphocytes (LGL) in AIDS cases; decrease in LGL cytotoxic activity in infected persons versus controls, along with increased lytic function induced by stimulation with recombinant interleukin-2 in both groups; and reduction of the CD4 population in AIDS patients, independent of the presence or absence of free serum antigen. Such research is helping to clarify the immunopathogenic mechanisms of HIV and possible geographic and demographic variations.