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

OBJECTIVE: To compare the immunogenicity of three yellow fever vaccines from WHO-17D and Brazilian 17DD substrains (different seed-lots). METHODS: An equivalence trial was carried out involving 1,087 adults in Rio de Janeiro. Vaccines produced by Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brazil) were administered following standardized procedures adapted to allow blocked randomized allocation of participants to coded vaccine types (double-blind). Neutralizing yellow fever antibody titters were compared in pre- and post-immunization serum samples. Equivalence was defined as a difference of no more than five percentage points in seroconversion rates, and ratio between Geometric Mean Titters (GMT) higher than 0.67. RESULTS: Seroconversion rates were 98% or higher among subjects previously seronegative, and 90% or more of the total cohort of vaccinees, including those previously seropositive. Differences in seroconversion ranged from -0.05% to -3.02%. The intensity of the immune response was also very similar across vaccines: 14.5 to 18.6 IU/mL. GMT ratios ranged from 0.78 to 0.93. Taking the placebo group into account, the vaccines explained 93% of seroconversion. Viremia was detected in 2.7% of vaccinated subjects from Day 3 to Day 7. CONCLUSIONS: The equivalent immunogenicity of yellow fever vaccines from the 17D and 17DD substrains was demonstrated for the first time in placebo-controlled double-blind randomized trial. The study completed the clinical validation process of a new vaccine seed-lot, provided evidence for use of alternative attenuated virus substrains in vaccine production for a major manufacturer, and for the utilization of the 17DD vaccine in other countries.

Influenza vaccination in Brazil: rationale and caveats

Mass vaccination campaigns against influenza in the elderly have been conducted in Brazil since 1999. A search of the literature on influenza in Brazil indicated that data on disease burden are still scarce and inaccurate. Published data seem to indicate that vaccination has produced some impact in the southern and southeastern regions but not in other regions of Brazil. A discussion of the technical and scientific rationale for mass immunization against influenza is presented and it is argued that the current strategy has not taken into account potential differences in disease occurrence in different areas. It is suggested some epidemiological surveillance actions needed to address major concerns regarding mass influenza vaccination and its impact in Brazil.

Fungal contamination: comparation between Portuguese poultries and swines

Animal confinement tends to increase the overall microbial load in the production environment caused by high amounts of feed and organic residuals (manure and wastewater) present in those environments. The number of animais and the handling and management required to work in these settings also contribute to enhance that microbial ioad. Animal housing typically exposes workers to substantial concentrations of bioaerosols, such as fungi and their metabolites. Therefore, agricultural workers, and especially pig and poultry farmers, are at increased risk of occupational respiratory diseases. Exposure to bioaerosols in poultries and swines may vary depending upon the stage of the animals' growth, density, manure management procedures, litter type and used floor coverage, among others. Gathering temporal information about the quantity and the composition of fungal load is necessary to better understand the relationship between these factors and adverse health symptoms of workers. This study aimed to characterize and compare fungal contamination between these two different settings.

Factors associated with infant feeding practices after hospital discharge

OBJECTIVE: To assess factors associated with infant feeding practices on the first day at home after hospital discharge. METHODS: A total of 209 women, who had a child aged four months or less and were living in Itapira, Brazil, were interviewed during the National Immunization Campaign Day in 1999. Statistical analysis was performed using the Chi-square test and a logistic regression model was used for verifying an association between dependent and independent variables. RESULTS: Women aged 25.5 years on average and 18.2% were teenagers. Fifty-three percent of the women delivered vaginally and most vaginal deliveries (78.5%) took place in the public hospital. The prevalence of exclusive breastfeeding on the first day at home was 78.1% and 11.6% of the infants were receiving formula at this time. The only factor associated with EBF on the first day at home was being a teenaged-primiparous mother (OR=9.40; 95% CI: 1.24-71.27). This association remained statistically significant even after controlling for type of delivery and hospital where the birth took place. Feeding formula on the first day at home was only significantly associated with the hospital (i.e., birth at the city hospital was a protective factor (OR=0.33; 95% CI: 0.13-0.86), even after controlling for vaginal delivery. CONCLUSIONS: On the first day at home after hospital discharge, teenaged-primiparous mothers were more likely to exclusive breastfeeding as well as those infants born in the municipal public hospital. Further studies are needed from a multidisciplinary approach.

Reactogenicity of yellow fever vaccines in a randomized, placebo-controlled trial

OBJECTIVE: To compare the reactogenicity of three yellow fever (YF) vaccines from WHO-17D and Brazilian 17DD substrains (different seed-lots) and placebo. METHODS: The study involved 1,087 adults eligible for YF vaccine in Rio de Janeiro, Brazil. Vaccines produced by Bio-Manguinhos, Fiocruz (Rio de Janeiro, Brazil) were administered ("day 0") following standardized procedures adapted to allow blinding and blocked randomization of participants to coded vaccine types. Adverse events after immunization were ascertained in an interview and in diary forms filled in by each participant. Liver enzymes were measured on days 0, 4-20 and 30 of the study. Viremia levels were measured on days 4 to 20 of follow-up. The immune response was verified through serologic tests. RESULTS: Participants were mostly young males. The seroconversion rate was above 98% among those seronegative before immunization. Compared to placebo, the excess risk of any local adverse events ranged from 0.9% to 2.5%, whereas for any systemic adverse events it ranged from 3.5% to 7.4% across vaccine groups. The excess risk of events leading to search for medical care or to interruption of work activities ranged from 2% to 4.5%. Viremia was detected in 3%-6% of vaccinees up to 10 days after vaccination. Variations in liver enzyme levels after vaccination were similar in placebo and vaccine recipients. CONCLUSIONS: The frequency of adverse events post-immunization against YF, accounting for the background occurrence of nonspecific signs and symptoms, was shown for the first time to be similar for vaccines from 17D and 17DD substrains. The data also provided evidence against viscerotropism of vaccine virus.

Determinants of vaccination after the Colombian health system reform

OBJECTIVE: To assess the effects of individual, household and healthcare system factors on poor children's use of vaccination after the reform of the Colombian health system. METHODS: A household survey was carried out in a random sample of insured poor population in Bogota, in 1999. The conceptual and analytical framework was based on the Andersen's Behavioral Model of Health Services Utilization. It considers two units of analysis for studying vaccination use and its determinants: the insured poor population, including the children and their families characteristics; and the health care system. Statistical analysis were carried out by chi-square test with 95% confidence intervals, multivariate regression models and Cronbach's alpha coefficient. RESULTS: The logistic regression analysis showed that vaccination use was related not only to population characteristics such as family size (OR=4.3), living area (OR=1.7), child's age (OR=0.7) and head-of-household's years of schooling (OR=0.5), but also strongly related to health care system features, such as having a regular health provider (OR=6.0) and information on providers' schedules and requirements for obtaining care services (OR=2.1). CONCLUSIONS: The low vaccination use and the relevant relationships to health care delivery systems characteristics show that there are barriers in the healthcare system, which should be assessed and eliminated. Non-availability of regular healthcare and deficient information to the population are factors that can limit service utilization.

Levantamento de anomalias nos sistemas impermeabilizantes de coberturas planas

As coberturas planas são um dos principais elementos construtivos de uma edificação, necessitando por isso de materiais com qualidade e certificados por organismos competentes, bem como de uma conceção e execução minuciosas. Em Portugal, os estudos sobre as anomalias realmente observadas em coberturas planas são ainda bastante reduzidos. Nesse âmbito, o presente trabalho teve como objetivo, efetuar o levantamento e a análise estatística das principais anomalias e causas identificadas em coberturas planas de 75 edifícios, permitindo assim a elaboração de um estudo que possa contribuir para a prevenção dessas anomalias e que indique também as medidas necessárias à reparação e os respetivos custos associados. As anomalias foram analisadas através da observação "in situ" das coberturas o que conduziu ao preenchimento de fichas de obra com os dados recolhidos. Da análise estatística efetuada aos edifícios, verificou-se que as principais anomalias detetadas estão relacionadas com perfurações e fissurações do sistema impermeabilizante, resultantes da falta de conhecimento dos utilizadores. Foi possível verificar erros de execução de remates em pontos singulares da cobertura, por falta de pormenores construtivos desses pontos ou erros de execução por parte do aplicador. Em muitos dos casos estudados, não foi detetada nenhuma anomalia, porque se considerou razoável considerar que o sistema impermeabilizante tenha atingido o fim de vida útil. O custo médio por metro quadrado associado à reabilitação de uma cobertura plana é influenciado principalmente por dois fatores: área e acessibilidade da cobertura. O tipo de anomalia e/ou a sua causa não determinaram o custo por metro quadrado da reparação efetuada, pois esta foi sempre de caracter integral e nunca pontual.

Barriers for HIV testing during pregnancy in Southern Brazil

OBJECTIVE: To assess HIV testing rate and determine risk factors for not have been tested during pregnancy. METHODS: A cross-sectional study was carried out in Porto Alegre, Southern Brazil, from December 2000 to February 2001. Socioeconomic, maternal and healthcare variables were obtained by means of a standardized questionnaire. Crude and adjusted odds ratios and their 95% confidence intervals were obtained in logistic regression models. RESULTS: A total of 1,642 mothers were interviewed. Of them, 94.3% reported being offered HIV testing before or during pregnancy or during labor; 89 mothers (5.4%) were not tested or did not know if they were tested. Attending fewer than six prenatal visits, being single and younger than 18 years old were relevant barriers preventing HIV testing. There was found a relationship between maternal schooling and the category of prenatal care provider. Having low 22.20 (12.43-39.67) or high 3.38 (1.86-7.68). schooling and being cared in the private sector strongly reduced the likelihood of being HIV tested. CONCLUSIONS: The Brazilian Health Ministry's recommendation for universal counseling and HIV testing has been successfully implemented in the public sector. In order to improve HIV testing coverage, new strategies need to target women cared in the private sector especially those of low schooling.

Avaliação da margem do PTV em tumores ginecológicos com irradiação dos gânglios lomboaórticos, que realizaram IMRT

Mestrado em Radioterapia.

Comparação do cálculo de dose com os algoritmos Analytical Anisotropic Algorithm e Pencil Beam Convolution na patologia de pulmão

Mestrado em Radioterapia.

Cellular uptake of BCG-loaded chitosan microparticles and in vivo evaluation of immune response following intranasal immunisation

Attenuated Mycobacterium bovis bacillus Calmette-Guérin (BCG) is the only currently available vaccine against tuberculosis. It is highly effective in pre-exposure immunisation against TB in children when administered by subcutaneous route to newborns. However, it does not provide permanent protection in adults. In this work, polymeric chitosan-alginate microparticles have been evaluated as potential nasal delivery systems and mucosal adjuvants for live attenuated BCG. Chitosan (CS) has been employed as adjuvant and mucosal permeation-enhancer, and, together with alginate (ALG), as additive to enhance BCG-loaded microparticles (MPs) cellular uptake in a human monocyte cell line, by particle surface modification. The most suitable particles were used for vaccine formulation and evaluation of immune response following intranasal immunisation of BALB/c mice.

Isolamento e caracterização de uma proteína tóxica produzida por um isolado açoriano de Bacillus weihenstephanensis

Dissertação de Mestrado, Biotecnologia em Controlo Biológico, 27 de Junho de 2013, Universidade dos Açores.

Estudo da reciclagem do banho de caleiro de pele caprina

Mestrado em Engenharia Química

Occupational exposure to Aflatoxin B1 in swine production and possible contamination sources

Although the adverse health consequences of ingestion of food contaminated with aflatoxin B1 (AFB1) are known, relatively few studies are available on the adverse effects of exposure in occupational settings. Taking this into consideration, our study was developed aiming to elucidate the possible effects of occupational exposure to AFB1 in Portuguese swine production facilities using a specific biomarker to assess exposure to AFB1. In total, 28 workers participated in this study, providing blood samples, and a control group (n  = 30) was composed of subjects without any type of agricultural activity. Fungal contamination was also studied by conventional methods through air, surfaces, and new and used floor coverage. Twenty-one workers (75%) showed detectable levels of AFB1 with values ranging from <1 ng/ml to 8.94 ng/ml and with a mean value of 1.91 ± 1.68 ng/ml. In the control group, the AFB1 values were all below 1 ng/ml. Twelve different Aspergillus species were identified. Aspergillus versicolor presented the highest airborne spore counts (3210 CFU/m3) and was also detected in higher values in surfaces (>300 CFU/cm2). Data indicate that exposure to AFB1 occurs in swine barns, and this site serves as a contamination source in an occupational setting.

Climatic patterns and physical controls of chlorophyll-a in the Northeast Atlantic

Tese de Doutoramento, Física, 17 de Dezembro de 2013, Universidade dos Açores.