Volunteers living in an area where schistosomiasis mansoni is endemic were subjected to ultrasound examination and classified into groups according to the levels of fibrosis diagnosed, namely, absence of indications of fibrosis (group 0), incipient fibrosis (group 1), and moderate/severe fibrosis (group 2). Peripheral blood mononuclear cells (PBMC) collected from the volunteers were stimulated with soluble antigens from adult schistosomes or from schistosome eggs, and the production of the cytokines gamma interferon, tumor necrosis factor alpha, transforming growth factor ␤ (TGF-␤), interleukin-4 (IL-4), IL-10, and IL-13 was determined. Potential associations of the level of fibrosis with age, sex, intensity of infection, and cytokine production were investigated between the three groups. Univariate analysis identified associations of age (>50), gender (male), and absence of eggs/g of feces with moderate/severe fibrosis and an association of intensity of infection (>100 eggs) with incipient fibrosis. When cytokine production in PBMC cultures stimulated by soluble egg antigens was categorized as low or high, significant differences in the distribution of IL-13 levels were established between groups 0 and 2. No significant differences were detected between the groups in the cytokines produced by PBMC cultures stimulated with soluble antigens from adult schistosomes. When all variables were tested in multivariate analyses, only IL-13 was strongly associated with fibrosis (odds ratio ‫؍‬ 5.8; 95% confidence interval [CI] ‫؍‬ 1

Com o objetivo de determinar o perfil clínico-epidemiológico dos acidentes ofídicos, em hospital do Estado do Acre, foram estudados prospectivamente 144 pacientes admitidos no período de janeiro a dezembro de 2002. Desses, 113 (78,5%) foram classificados como vítimas de acidente com envenenamento. Os gêneros Bothrops, Lachesis e Micrurus foram responsáveis por, respectivamente, 75,7%, 2,1% e 0,7% dos casos. Os acidentes predominaram em pessoas do sexo masculino (78,5%), trabalhadores rurais (51,4%) e com idades entre 10 e 29 anos (43,8%). Nos acidentes botrópicos, os envenenamentos considerados moderados (48,6%) prevaleceram sobre os leves (31,2%) e graves (20,2%). Dois casos envolvendo o gênero Bothrops não receberam terapia antipeçonha. Entretanto, soro heterólogo foi administrado em 23 vítimas de acidente sem envenenamento. Concluindo, os resultados obtidos neste estudo diferiram dos observados por outros autores quanto à gravidade dos casos e adequação do tratamento, indicando a necessidade de treinamento da equipe.

Alien invasive species represent a severe risk to biodiversity. Such is the case of buffel grass (Cenchrus ciliaris L.), a native species of Southern Asia and East Africa, which was introduced to the United States and Mexico for use in improved pasture. Here we present a coarse-grain approach to determine areas where buffel grass can potentially invade in Mexico. Potential species distributions, suitable for an invasion by buffel grass, were obtained through genetic algorithms. We generated the algorithms with databases of herbaria specimens; environmental digital covers of climate, soil texture, and vegetation; and the program called Genetic Algorithm for Rule-Set Prediction. This spatial modeling approach was validated with a case study for the state of Sonora, Mexico, where the occurrence of buffel grass has been proven. The most threatened vegetation types for the specific case of Sonora were desert scrub, mesquite woodlands, and tropical deciduous forest. The model prediction agreed with the field observations recorded in Sonora and allowed us to apply the same procedure to produce a map of the potential sites of buffel grass invasion for Mexico. The areas at risk of invasion mostly occurred in desert scrub, located in the arid and semiarid regions of northern Mexico. This methodology provides an initial baseline for assessment, prevention, and management of alien species that may become invasive under certain environmental conditions. Additionally this modeling approach provides a tool for policy makers to use in making decisions on land-use management practices when alien species are involved. Resumen: Las especies exóticas invasoras representan un riesgo para la biodiversidad. Tal es el caso deCenchrus ciliaris, una especie nativa del sureste de Asia y este deÁfrica, que fue introducida a los Estados Unidos y México como un pasto mejora de pasturas. Presentamos un método de grano grueso para determinaráreas que potencialmente pueden ser invadidas por C. ciliaris en México. Las distribuciones potenciales deáreas susceptibles de invasión por C. ciliaris, se obtuvieron por medio de algoritmos genéticos. Generamos los algoritmos con bases de datos de especímenes de herbario, coberturas ambientales digitales (i. e. clima, textura del suelo y vegetación) y el programa Genetic Algorithm for Rule-Set Prediction. Este método de modelado espacial fue validado con un estudio de caso para el estado de Sonora, México, donde se había probado la ocurrencia de C. ciliaris. Para el caso específico de Sonora, los tipos de vegetación más amenazados

In order to understand the determinants of human infection by Leishmania chagasi in an urban area, a cross-sectional population based study was conducted using molecular and serologic methods to identify infection. Participants were interviewed using a pre-coded questionnaire. Two criteria were tested to identify risk factors: Model 1-including all participants positive in hybridization by Leishmania donovani complex probe; Model 2-including all participants positive for hybridization and at least one serologic test. In Model 1, the variables associated with infection were: ownership of birds, time spent outside house between 6:00-10:00 PM and garbage not collected. In Model 2, the variables associated with infection were: family with knowledge of the vector, garbage not collected, garbage not removed or buried, ownership of birds and eroded areas in the neighborhood. The risk factors identified were associated with household conditions, presence of animals and the likelihood of contact with phlebotomine sandflies. Key-words: Visceral leishmaniasis. Kala-Azar. Leishmania chagasi. Asymptomatic infection. Risk factors. RESUMOCom o objetivo de identificar os determinantes da infecção humana por Leishmania chagasi em uma área urbana, foi realizado um estudo seccional de base populacional utilizando-se métodos moleculares e sorológicos para identificar a infecção. Os participantes foram entrevistados utilizando-se questionário pré-codificado. Dois critérios foram testados para identificar os fatores de risco: Modelo 1-incluindo todos os participantes positivos na hibridização com sonda para o complexo Leishmania donovani; Modelo 2-incluindo todos os participantes positivos na hibridização e em pelo menos um teste sorológico. No Modelo 1, as variáveis associadas à infecção foram: criar pássaros, encontrar-se fora de casa entre 18:00-22:00h e não ter o lixo coletado. No Modelo 2, as variáveis associadas à infecção foram: família conhecer o vetor, não ter o lixo coletado, lixo não removido ou queimado, criar pássaros, proximidade de áreas erodidas. Os fatores de risco identificados foram associados às condições das moradias, presença de animais e probabilidade de contato com flebotomíneos. Palavras-chaves: Leishmaniose visceral. Calazar. Leishmania chagasi. Infecção assintomática. Fatores de risco.

BackgroundOne of the most important drawbacks in visceral leishmaniasis (VL) population studies is the difficulty of diagnosing asymptomatic carriers. The aim of this study, conducted in an urban area in the Southeast of Brazil, was to evaluate the performance of serology to identify asymptomatic VL infection in participants selected from a cohort with a two-year follow-up period.MethodologyBlood samples were collected in 2001 from 136 cohort participants (97 positive and 39 negatives, PCR/hybridization carried out in 1999). They were clinically evaluated and none had progressed to disease from their asymptomatic state. As controls, blood samples from 22 control individuals and 8 patients with kala-azar were collected. Two molecular biology techniques (reference tests) were performed: PCR with Leishmania-generic primer followed by hybridization using L. infantum probe, and PCR with specific primer to L. donovani complex. Plasma samples were tested by ELISA using three different antigens: L. infantum and L. amazonensis crude antigens, and rK39 recombinant protein. Accuracy of the serological tests was evaluated using sensitivity, specificity, likelihood ratio and ROC curve.FindingsThe presence of Leishmania was confirmed, by molecular techniques, in all kala-azar patients and in 117 (86%) of the 136 cohort participants. Kala-azar patients showed high reactivity in ELISAs, whereas asymptomatic individuals presented low reactivity against the antigens tested. When compared to molecular techniques, the L. amazonensis and L. infantum antigens showed higher sensitivity (49.6% and 41.0%, respectively) than rK39 (26.5%); however, the specificity of rK39 was higher (73.7%) than L. amazonensis (52.6%) and L. infantum antigens (36.8%). Moreover, there was low agreement among the different antigens used (kappa<0.10).ConclusionsSerological tests were inaccurate for diagnosing asymptomatic infections compared to molecular methods; this could lead to misclassification bias in population studies. Therefore, studies which have used serological assays to estimate prevalence, to evaluate intervention programs or to identify risk factors for Leishmania infection, may have had their results compromised.

Background Studies analyzing motivation factors that lead to blood donation have found altruism to be the primary motivation factor; however social capital has not been analyzed in this context. Our study examines the association between motivation factors (altruism, self-interest and response to direct appeal) and social capital (cognitive and structural) across three large blood centers in Brazil. Study Design and Methods We conducted a cross-sectional survey of 7,635 donor candidates from October 15 through November 20, 2009. Participants completed self-administered questionnaires on demographics, previous blood donation, HIV testing and knowledge, social capital and donor motivations. Enrollment was determined prior to the donor screening process. Results Among participants, 43.5% and 41.7% expressed high levels of altruism and response to direct appeal respectively, while only 26.9% expressed high levels of self-interest. More high self-interest was observed at Hemope-Recife (41.7%). Of participants, 37.4% expressed high levels of cognitive social capital while 19.2% expressed high levels of structural social capital. More high cognitive and structural social capital was observed at Hemope-Recife (47.3% and 21.3%, respectively). High cognitive social capital was associated with high levels of altruism, self-interest and response to direct appeal. Philanthropic and high social altruism was associated with high levels of altruism and response to direct appeal. Conclusion Cognitive and structural social capital and social altruism are associated with altruism and response to direct appeal, while only cognitive social capital is associated with self-interest. Designing marketing campaigns with these aspects in mind may help blood banks attract potential blood donors more efficiently.

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BackgroundBovine vaccinia (BV) is a zoonosis caused by Vaccinia virus, a virus from Orthopoxvirus genus (OPV) that affects mainly cattle herds and humans in rural areas in Brazil. Because most studies have focused on outbreaks situations, data on BV epidemiology is limited. A cross sectional study in Brazilian rural areas during 2012–2013 was conducted to determine the neutralizing antibodies seroprevalence and risk factors for BV.MethodsA structured questionnaire was applied to elicit demographics data and farming practices considered risk factors for BV exposure. Neutralizing anti-OPV antibodies were investigated using plaque reduction neutralization test. The neutralizing antibodies prevalence rates were calculated and the risk factor analysis was performed using multivariate logistic regression.ResultsTwo hundred and forty participants were enrolled in this study with a prevalence of neutralizing antibodies of 30.8 % (95 % confidence interval [CI], 25.3–36.9). In multivariate analysis, age > 35 years (Odds Ratio [OR] = 18.2; CI 95 % = 7.7 – 43.2) and previous outbreak in property (OR = 3.9; C I95 % = 1.2 – 12.6) were independently associated with anti-OPV neutralizing antibodies.ConclusionsIn this study, anti-OPV protective immunity (neutralizing antibody titers) was assessed in an endemic BV Brazilian rural area. Our findings indicate that epidemiological surveillance is required and should be applied by public health authorities to create interventions and/or prevention strategies to avoid viral spread causing future outbreaks among individuals who are under risk of infection.