ABSTRACT
BACKGROUND: As the most frequent pathway of vertical transmission of HTLV-1 is breast-feeding, and considering the higher prevalence in women, it is very important to perform screening examinations for anti-HTLV-1 antibodies as part of routine prenatal care. So far, no studies of HTLV-1 seroprevalence in pregnant women in the Southern region of Bahia, Brazil, have been described. METHODS: Pregnant women were selected at the two regional reference centers for health care from Southern Bahia. A total of 2766 pregnant women attending the antenatal unit between November 2008 and May 2010 have been analyzed. An extra blood sample was drawn during their routine antenatal testing. A standardized questionnaire was applied and all positive plasma samples were tested by ELISA and were confirmed by Western Blot and PCR. Besides that, positive women were contacted and visited. The family members that were present during the visit were asked to be serologically screened to the virus. A prospective study was also carried out and newborns were followed up to two years for evaluation of vertical transmission. RESULTS: HTLV prevalence was 1.05% (CI 95%: 0.70-1.50). There was no association of HTLV-1 infection with age, education, income and ethnic differences. The association with marital status was borderline (OR = 7.99; 95% CI 1.07-59.3; p = 0.042). In addition, 43 family members of the HTLV-1 seropositive women have been analyzed and specific reactivity was observed in 32.56%, including two children from previous pregnancy. CONCLUSION: It is very important to emphasize that the lack of HTLV-1 screening in pregnant women can promote HTLV transmission especially in endemic areas. HTLV screening in this vulnerable population and the promotion of bottle-feeding for children of seropositive mothers could be important cost-effective methods to limit the vertical transmission. Besides that, our data reinforce the need to establish strategies of active surveillance in household and family contacts as important epidemiological surveillance actions for the early detection of virus infection and the prevention of transmission by sexual or and parenteral contact.
Subject(s)
HTLV-I Infections/epidemiology , Human T-lymphotropic virus 1/isolation & purification , Pregnancy Complications, Infectious/epidemiology , Adolescent , Adult , Blotting, Western , Brazil/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Female , HTLV-I Infections/virology , Humans , Male , Polymerase Chain Reaction , Pregnancy , Pregnancy Complications, Infectious/virology , Prevalence , Surveys and Questionnaires , Young AdultABSTRACT
A prevalência de HTLV- 1 no Brasil é diversa, dependendo tanto da região geográfica quanto do grupo analisado. Um estudo populacional realizado em Salvador detectou prevalência de 1,76%, além de maior prevalência em mulheres e associação com menores níveis de escolaridade e renda. Como a via mais frequente de transmissão vertical do HTLV-1 é a amamentação e considerando a maior prevalência nas mulheres, é muito importante a realização de exames de triagem para HTLV-1 como parte do prénatal. Até o momento, não existem estudos publicados sobre a soroprevalência do HTLV-1 em gestantes na região sul da Bahia. No presente estudo, as gestantes foram selecionadas em dois centros de referência regionais de saúde do sul da Bahia. Um total de 2.766 gestantes atendidas na sala de pré-parto entre novembro de 2008 e maio de 2010 foram analisados. Um questionário foi aplicado, e todas as amostras de plasma reagentes foram testadas em duplicata e confirmadas por Western blot e PCR. Além disso, mulheres positivas foram contactadas e visitadas. Os membros da família que estavam presentes durante a visita foram convidados a serem testados para o HTLV...
The prevalence of HTLV-1 in Brazil is diverse, depending on both the geographic region and the group analyzed. A study conducted on general population revealed that the prevalence in Salvador was 1.76%. Besides, it was also found that the prevalence was higher amongst women and that the virus was associated with lower education and lower income. As the most frequent pathway of vertical transmission of HTLV-1 is breast-feeding, and considering the higher prevalence in women, it is very important to perform screening examinations for anti-HTLV-1...
Subject(s)
Humans , Pregnancy/immunology , Pregnancy/blood , Deltaretrovirus Infections/diagnosis , Deltaretrovirus Infections/immunology , Deltaretrovirus Infections/prevention & control , Virus Diseases/diagnosis , Virus Diseases/immunologyABSTRACT
To estimate HIV-1 seroprevalence in the general population of Salvador, Bahia, Brazil, we conducted a cross-sectional survey of 3,437 residents from 1998 to 2000. Subjects were drawn from 30 sentinel areas representing a wide range of living conditions. Plasma samples were screened for HIV-1 antibodies by ELISA and confirmed by immunofluorescent assay. Subtype determination by HMA was performed after proviral DNA amplification. Phylogenetic analysis using parsimony was performed with the neighbor-joining method. Overall HIV-1 seroprevalence was 0.55 percent (19/3,446): 0.8 percent for men and 0.36 percent for women. Seroprevalence was higher in the 31-45-year age group (1 percent) and among persons with family income less than twice the minimum wage (0.78 percent) as compared to 0.33 percent for the higher income group. Syphilis was detected in 37 percent of HIV seropositive individuals. Phylogenetic inferences identified 10 samples as subtype B in the env region and 2 samples with Benv/Fgag/Fpol and Fenv/Bgag. Age > 30 years, male gender, and income < 2 times the minimum wage were identified as risk factors for HIV-1 infection. Extrapolating the proportion of seropositive individuals to Salvador, the number of HIV-1 infected individuals was estimated at 13,750.
A seroprevalência do HIV-1 na população geral de Salvador, Bahia, Brasil, foi estimada em estudo de corte transversal com 3.437 indivíduos entre 1998-2000, residentes de 30 áreas sentinelas com ampla va-riedade de condições de vida. Realizou-se uma triagem para anticorpos anti-HIV-1 por ELISA e confirmados por imunofluorescência. A determinação do subtipo foi realizada por HMA, após amplificação do DNA proviral. As análises filogenéticas foram realizadas com PAUP utilizando os algoritmos neighbor-joining. A seroprevalência do HIV-1 foi de 0,55 por cento (19/3.446): 0,8 por cento para os homens e 0,36 por cento para as mulheres. A seroprevalência foi mais alta no grupo de 31-45 anos (1 por cento) e entre as pessoas com renda familiar inferior a dois salários mínimos (0,78 por cento). A sífilis foi diagnosticada em 37 por cento dos participantes HIV soropositivos. A análise filogenética identificou 10 amostras como subtipo B na região env, e duas amostras Benv/Fgag/Fpol e Fenv/Bgag. Idade > 30 anos, sexo masculino, renda < 2 salários mínimos se comportaram como fatores de riscos para a infecção por HIV-1. Se extrapolarmos a proporção de soropositivos para Salvador, o número de infectados pelo HIV seria 13.750.
Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , HIV Seroprevalence , HIV-1 , HIV Infections/epidemiology , Brazil/epidemiology , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Seroepidemiologic StudiesABSTRACT
To estimate HIV-1 seroprevalence in the general population of Salvador, Bahia, Brazil, we conducted a cross-sectional survey of 3,437 residents from 1998 to 2000. Subjects were drawn from 30 sentinel areas representing a wide range of living conditions. Plasma samples were screened for HIV-1 antibodies by ELISA and confirmed by immunofluorescent assay. Subtype determination by HMA was performed after proviral DNA amplification. Phylogenetic analysis using parsimony was performed with the neighbor-joining method. Overall HIV-1 seroprevalence was 0.55% (19/3,446): 0.8% for men and 0.36% for women. Seroprevalence was higher in the 31-45-year age group (1%) and among persons with family income less than twice the minimum wage (0.78%) as compared to 0.33% for the higher income group. Syphilis was detected in 37% of HIV seropositive individuals. Phylogenetic inferences identified 10 samples as subtype B in the env region and 2 samples with Benv/Fgag/Fpol and Fenv/Bgag. Age > or = 30 years, male gender, and income < or = 2 times the minimum wage were identified as risk factors for HIV-1 infection. Extrapolating the proportion of seropositive individuals to Salvador, the number of HIV-1 infected individuals was estimated at 13,750.
Subject(s)
Genes, Viral/genetics , HIV Antibodies/blood , HIV Infections/epidemiology , HIV Seroprevalence , HIV-1/genetics , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Brazil/epidemiology , Child , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Epidemiologic Methods , Female , HIV Infections/virology , HIV-1/immunology , HIV-1/isolation & purification , Hepatitis C Antibodies/analysis , Humans , Infant , Male , Middle Aged , Molecular Epidemiology , Sex Distribution , Socioeconomic Factors , Urban PopulationABSTRACT
Patients infected with HIV-1 develop a potent humoral immune response against the virus, but HIV-1 primary isolates are remarkably resistant to neutralizing antibodies. Considering that the envelope glycoprotein of HIV-1 (gp120/41) is heavily glycosylated, we investigated whether anti-carbohydrate antibodies could inhibit HIV-1 infection in vitro. We studied the neutralizing activity of three monoclonal antibodies (mAbs) raised to carbohydrates of Schistosoma mansoni, against seven primary isolates of HIV-1. Assays were performed infecting peripheral blood mononuclear cells from normal donors with viral isolates previously treated with mAbs. Viral strains used were tropic for the coreceptors CCR5, CXCR4, and dual-tropic ones. We found that the anti-glycan mAbs vigorously inhibited HIV-1 infection, regardless of the preferential coreceptor usage of the isolate, in a dose-response manner. Importantly, five isolates were resistant to neutralization by two HIV-1 antibody-positive human sera endowed with potent anti-HIV-1 inhibitory activity. Our findings suggest that carbohydrates of the HIV-1 viral envelope may be a target of an effective humoral immune response elicited by vaccination.
