Psychosocial factors and T lymphocyte counts in Brazilian peacekeepers.

OBJECTIVE: To investigate the associations between psychosocial factors and peripheral blood CD4 and CD8 T lymphocyte numbers in Brazilian peacekeepers. METHODS: Venous blood was collected from 759 peacekeepers who had just returned from a peace mission in Haiti. Among the 759 soldiers, 642 individuals completed the psychosocial measures. CD4 and CD8 T lymphocyte counts were measured by flow cytometry using a commercially available kit. Psychosocial factors, including military peace force stressors, clinical stress, anxiety and depression, were recorded. As a reference for T lymphocyte numbers, we measured T lymphocyte counts in 75 blood donors from the Instituto de Biologia do Exército, Rio de Janeiro. RESULTS: The median numbers of CD4 and CD8 T lymphocytes in the blood donors were 819 cells/µl and 496 cells/µl, respectively, with a CD4:CD8 ratio of 1.6. Significantly (p<0.05) lower CD4 T cell counts (759 cells/µl) were recorded for peacekeepers, with similar CD8 levels (548 cells/µl) and smaller CD4:CD8 ratios (1.3, p<0.001) compared to blood donors. These differences were due to a group of 14 military personnel with CD4 and CD8 medians of 308 and 266 cells/µl, respectively. Only one (7.1%) of these 14 individuals was diagnosed with clinical stress compared with 13.5% of the individuals with normal levels of CD4 T lymphocytes. One individual out of 628 (0.16%) had a Lipp's Stress Symptom Inventory score of 3, indicating near exhaustion. CONCLUSION: The prevalence of psychological disorders was low and there were no associations with CD4 or CD8 T cell numbers.

Mutations in the nef and vif genes associated with progression to AIDS in elite controller and slow-progressor patients.

Progression towards AIDS can vary from 5 to 10 years from the establishment of the primary infection by HIV-1 to more than 10 years in the complete absence of antiretroviral therapy. Several factors can contribute to the outcome of HIV infection, including host genetic and viral replicating characteristics. Historically, nef-deleted viral genomes have been associated with disease progression. Therefore, the lentiviral Nef protein is regarded as a progression factor. The objective of this work was to characterize the nef gene from a group of treatment naive patients infected with HIV-1 for more than 10 years. These patients were classified as long-term non-progressors, elite controller, and slow-progressors according to clinical and laboratorial data. A premature stop codon within the nef gene leading to the expression of a truncated peptide was observed on samples from the elite controller patient. For the slow-progressor patients, several degrees of deletions at the C-terminal of Nef were observed predicting a loss of function of this protein. The vif gene was characterized for these patients and a rare mutation that predicts a miss localization of the Vif protein to the nucleus of infected cells that could prevent its function as an APOBEC neutralization factor was also observed. These data indicate the importance of the HIV accessory proteins as factors that contribute to the outcome of AIDS.

Diphtheria Antibodies and T lymphocyte Counts in Patients Infected with HIV-1

We assessed the IgG levels anti-diphtheria (D-Ab) and T cell counts (CD4+ and CD8+) in HIV-1 infected subjects undergoing or not highly active antiretroviral therapy (HAART). Approximately 70% of all HIV-1 patients were unprotected against diphtheria. There were no differences in D-Ab according to CD4 counts. Untreated patients had higher D-Ab (geometric mean of 0.62 IU/ml) than HAART-patients (geometric mean of 0.39 IU/ml). The data indicated the necessity of keeping all HIV-1 patients up-to-date with their vaccination.

Diphtheria Antibodies and T lymphocyte Counts in Patients Infected With HIV-1.

We assessed the IgG levels anti-diphtheria (D-Ab) and T cell counts (CD4+ and CD8+) in HIV-1 infected subjects undergoing or not highly active antiretroviral therapy (HAART). Approximately 70% of all HIV-1 patients were unprotected against diphtheria. There were no differences in D-Ab according to CD4 counts. Untreated patients had higher D-Ab (geometric mean of 0.62 IU/ml) than HAART-patients (geometric mean of 0.39 IU/ml). The data indicated the necessity of keeping all HIV-1 patients up-to-date with their vaccination.

Temporal trends of HIV-related risk behavior among Brazilian military conscripts, 1997-2002.

PURPOSE: To present selected results of military conscript surveys related to HIV/AIDS, conducted in Brazil, 1997-2002. METHODS: Questionnaires including information on socio-demographic data, sexual behavior practices, sexually transmitted infections-related problems, and use of injecting drugs were completed by 30970 individuals, obtained through a 2-stage sampling. An index of sexual risk behavior was developed to take into account multiplicity of partners and irregularity of condom use. The HIV infection prevalence rate was estimated for 2002. Logistic regression was used to identify the most important determinants of HIV infection. RESULTS: The percentage of regular condom use increased from 38% (1997) to 49% (2002), and the index of sexual risk behavior decreased from 0.98 in 1997 to 0.87, in 2002. The HIV infection prevalence rate was 0.09%, in 2002, which remained unchanged since 1998 Riskier sexual practices among young men with incomplete education and among "men who have sex with men" were found as well as among the participants who reported at least one sexually transmitted infections - related problem. The most important predictor of HIV infection was to be positive for syphilis. CONCLUSIONS: The estimated value of the HIV infection prevalence supports the diagnosis of a concentrated HIV epidemic, in Brazil. Results indicate that particular attention needs to be paid for regional differentials, and for special subgroups, in Brazil.

Temporal trends of HIV-related risk behavior among brazilian military conscripts, 1997-2002

OBJETIVO: Apresentar determinados resultados de levantamentos sobre HIV/AIDS em conscritos do Exército Brasileiro, conduzidos em 1997-2002. MÉTODOS: Aplicaram-se questionários em 30970 conscritos, selecionados segundo um esquema de amostragem em 2 estágios, para obter informações sobre comportamento sexual, problemas relacionados a infecções sexualmente transmitidas e uso de drogas injetáveis. Desenvolveu-se um índice de comportamento sexual de risco para contemplar multiplicidade de parceria sexual e uso de preservativo. Estimou-se, para o ano de 2002, a taxa de prevalência de infecção pelo HIV. RESULTADOS: A porcentagem de uso regular de preservativo aumentou de 38%, em 1997, para 49%, em 2002. O índice de comportamento sexual de risco decresceu de 0,98 em 1997 para 0,87, em 2002. O índice de prevalência de infecção HIV foi de 0.09%, in 2002, permanecendo inalterado desde 1998 Práticas sexuais de maior risco foram observadas entre aqueles com baixa escolaridade e em "homens que fazem sexo com homens", como também entre aqueles com problemas de infecções sexualmente transmissíveis. O mais importante preditor de infecção pelo HIV foi a soropositividade para lues. CONCLUSÕES: A prevalência estimada de infeção pelo HIV suporta o diagnóstico que a epidemia de AIDS, no Brasil, é do tipo "concentrada". Os resultados indicam que são necessárias medidas de intervenção que contemplem diferenças regionais e também voltadas para subgrupos populacionais especiais.

Seroprevalence of hepatitis B and C in Brazilian army conscripts in 2002: a cross-sectional study

Hepatitis B and C constitute important public health problems worldwide. In Brazil, studies on prevalence of viral hepatitis have local and regional characteristics; consequently it is difficult to define the national epidemiological situation. Our objective was to evaluate the seroprevalence of hepatitis B and C in conscripts of the Brazilian Army. A transversal study among males aged 17 to 22 years was conducted nationwide. After informed consent, each volunteer filled in a social-behavioral questionnaire and had blood drawn to test for HBsAg and anti-HCV. A total of 7,372 volunteers were evaluated in the second half of 2002. The prevalence of HBsAg was 2.6 percent (95 percent confidence interval: 2.2, 3.0) and that of anti-HCV was 1.5 percent (95 percent confidence interval: 1.2, 1.8). A wide variation among macro regions and states in the same region was observed for both markers. In conclusion, although this population theoretically had a low risk for HBV and HCV infection, these results are higher than expected for this age range. These findings may indicate a change in the pattern of HBV and HCV transmission in Brazil. Due to the different dynamics of these epidemics, further studies are warranted to confirm these apparent trends.

Seroprevalence of hepatitis B and C in Brazilian army conscripts in 2002: a cross-sectional study.

Hepatitis B and C constitute important public health problems worldwide. In Brazil, studies on prevalence of viral hepatitis have local and regional characteristics; consequently it is difficult to define the national epidemiological situation. Our objective was to evaluate the seroprevalence of hepatitis B and C in conscripts of the Brazilian Army. A transversal study among males aged 17 to 22 years was conducted nationwide. After informed consent, each volunteer filled in a social-behavioral questionnaire and had blood drawn to test for HBsAg and anti-HCV. A total of 7,372 volunteers were evaluated in the second half of 2002. The prevalence of HBsAg was 2.6% (95% confidence interval: 2.2, 3.0) and that of anti-HCV was 1.5% (95% confidence interval: 1.2, 1.8). A wide variation among macro regions and states in the same region was observed for both markers. In conclusion, although this population theoretically had a low risk for HBV and HCV infection, these results are higher than expected for this age range. These findings may indicate a change in the pattern of HBV and HCV transmission in Brazil. Due to the different dynamics of these epidemics, further studies are warranted to confirm these apparent trends.

Immunogenicity of WHO-17D and Brazilian 17DD yellow fever vaccines: a randomized trial

OBJETIVO: Comparar a imunogenicidade de três vacinas contra febre amarela ) das subcepas WHO-17D e 17DD brasileira (diferentes lotes-semente). MÉTODOS: Trata-se de ensaio de equivalência envolvendo 1.087 adultos no Rio de Janeiro, RJ. As vacinas foram produzidas em Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brasil) e foram administradas seguindo procedimentos adaptados para randomização em blocos, com tipos de vacinas codificados ("duplo-cego"). Anticorpos neutralizantes contra febre amarela foram dosados antes e depois da vacinação. Definiu-se equivalência como diferença nas taxas de soroconversão não superior a cinco pontos percentuais, e razão de títulos médios geométricos superior (TMG) a 0,67. RESULTADOS: As taxas de soroconversão foram iguais ou maiores do que 98 por cento nos participantes previamente soronegativos. Na coorte completa (incluindo os previamente soropositivos) a soroconversão foi igual ou superior a 90 por cento. As diferenças na soroconversão variaram de -0,05 por cento a -3,02 por cento entre os grupos de comparação. A intensidade da resposta imune também foi semelhante nos grupos: 14,5 UI/mL a 18,6 UI/mL. As razões de TMG variaram de 0,78 a 0,93. Considerando o grupo placebo, as vacinas explicaram 93 por cento da soroconversão. Viremia foi detectada entre os dias três e sete em 2,7 por cento dos participantes vacinados. CONCLUSÕES: A equivalência na imunogenicidade das vacinas contra a febre amarela das subcepas 17D e 17DD foi demonstrada pela primeira vez em ensaio clínico randomizado, duplo-cego, controlado com placebo. O estudo completou o processo de validação clínica do novo lote-semente de vacina, além de ampliar as bases para utilização da vacina brasileira em outros países e de trazer alternativas de subcepas para o produtor da vacina no Brasil.

Prevalence of human immunodeficiency virus drug resistance mutations and subtypes in drug-naive, infected individuals in the army health service of Rio de Janeiro, Brazil.

The prevalence of mutations that confer resistance to antiretroviral drugs was examined in 56 drug-naive, human immunodeficiency virus type 1 (HIV-1)-infected individuals from the Army Health Service in Rio de Janeiro, Brazil. No primary protease inhibitor mutations were found, but secondary mutations were observed in 51.2% of the samples. Fourteen percent of the viruses had reverse transcriptase inhibitor-associated mutations. Comparative analysis of protease secondary mutations from four different time periods in drug-naive patients in the city of Rio de Janeiro has indicated constant rates for particular mutations. Changes in CD4 cell counts and HIV viral load over time in subtype B- and non-B-infected drug-naive patients were not significantly different.