Spatial point analysis based on dengue surveys at household level in central Brazil

<p>Abstract</p> <p>Background</p> <p>Dengue virus (DENV) affects nonimunne human populations in tropical and subtropical regions. In the Americas, dengue has drastically increased in the last two decades and Brazil is considered one of the most affected countries. The high frequency of asymptomatic infection makes difficult to estimate prevalence of infection using registered cases and to locate high risk intra-urban area at population level. The goal of this spatial point analysis was to identify potential high-risk intra-urban areas of dengue, using data collected at household level from surveys.</p> <p>Methods</p> <p>Two household surveys took place in the city of Goiania (~1.1 million population), Central Brazil in the year 2001 and 2002. First survey screened 1,586 asymptomatic individuals older than 5 years of age. Second survey 2,906 asymptomatic volunteers, same age-groups, were selected by multistage sampling (census tracts; blocks; households) using available digital maps. Sera from participants were tested by dengue virus-specific IgM/IgG by EIA. A Generalized Additive Model (GAM) was used to detect the spatial varying risk over the region. Initially without any fixed covariates, to depict the overall risk map, followed by a model including the main covariates and the year, where the resulting maps show the risk associated with living place, controlled for the individual risk factors. This method has the advantage to generate smoothed risk factors maps, adjusted by socio-demographic covariates.</p> <p>Results</p> <p>The prevalence of antibody against dengue infection was 37.3% (95%CI [35.5–39.1]) in the year 2002; 7.8% increase in one-year interval. The spatial variation in risk of dengue infection significantly changed when comparing 2001 with 2002, (ORadjusted = 1.35; p < 0.001), while controlling for potential confounders using GAM model. Also increasing age and low education levels were associated with dengue infection.</p> <p>Conclusion</p> <p>This study showed spatial heterogeneity in the risk areas of dengue when using a spatial multivariate approach in a short time interval. Data from household surveys pointed out that low prevalence areas in 2001 surveys shifted to high-risk area in consecutive year. This mapping of dengue risks should give insights for control interventions in urban areas.</p

Genomic Surveillance of Yellow Fever Virus Epizootic in São Paulo, Brazil, 2016 – 2018

São Paulo, a densely inhabited state in southeast Brazil that contains the fourth most populated city in the world, recently experienced its largest yellow fever virus (YFV) outbreak in decades. YFV does not normally circulate extensively in São Paulo, so most people were unvaccinated when the outbreak began. Surveillance in non-human primates (NHPs) is important for determining the magnitude and geographic extent of an epizootic, thereby helping to evaluate the risk of YFV spillover to humans. Data from infected NHPs can give more accurate insights into YFV spread than when using data from human cases alone. To contextualise human cases, identify epizootic foci and uncover the rate and direction of YFV spread in São Paulo, we generated and analysed virus genomic data and epizootic case data from NHPs in São Paulo. We report the occurrence of three spatiotemporally distinct phases of the outbreak in São Paulo prior to February 2018. We generated 51 new virus genomes from YFV positive cases identified in 23 different municipalities in São Paulo, mostly sampled from NHPs between October 2016 and January 2018. Although we observe substantial heterogeneity in lineage dispersal velocities between phylogenetic branches, continuous phylogeographic analyses of generated YFV genomes suggest that YFV lineages spread in São Paulo at a mean rate of approximately 1km per day during all phases of the outbreak. Viral lineages from the first epizootic phase in northern São Paulo subsequently dispersed towards the south of the state to cause the second and third epizootic phases there. This alters our understanding of how YFV was introduced into the densely populated south of São Paulo state. Our results shed light on the sylvatic transmission of YFV in highly fragmented forested regions in São Paulo state and highlight the importance of continued surveillance of zoonotic pathogens in sentinel species

Encontro de Haemagogus (Conopostegus) leucocelaenus (Diptera: Culicidae), no Município de Porto Alegre, Estado do Rio Grande do Sul Finding of Haemagogus (Conopostegus) leucocelaenus (Diptera: Culicidae), in the municipality of Porto Alegre, State of Rio Grande do Sul

Em novembro de 2006, foi realizada uma investigação entomológica numa mata nativa do município de Porto Alegre, Estado do Rio Grande do Sul. O resultado foi a captura de várias espécies Culicidae, incluindo o primeiro registro da presença de Haemagogus leucocelaenus na localidade. Esta espécie é considerada vetora do vírus da febre amarela em alguns municípios do Estado, motivando esta comunicação para alertar sobre o potencial da área para circulação do agente etiológico desta doença.<br>In November 2006, an entomological investigation was carried out in a native forest in the municipality of Porto Alegre, State of Rio Grande do Sul. The result was the capture of several Culicidae species, including the first recording of the presence of Haemagogus leucocelaenus in this locality. This species is considered to be a vector for the yellow fever virus in some municipalities of this State, and this was the motivation for the present communication, in order to warn regarding the potential of this area for circulation of the etiological agent for this disease

Perfil da composição química e atividades antibacteriana e antioxidante do óleo essencial do cravo-da-índia (Eugenia caryophyllata Thunb.)

A busca por substâncias antibacterianas e antioxidantes naturais tem sido alvo de diversos estudos científicos. Foi objetivo determinar as atividades antibacteriana e antioxidante e a concentração inibitória mínima do óleo essencial do cravo-da-índia, obtido por hidrodestilação. O estudo por CG-EM identificou o eugenol como o constituinte majoritário do óleo essencial e os testes de atividade antibacteriana mostraram bons resultados para quase todos os microorganismos avaliados. Os valores de concentração inibitória mínima variaram de 0,2 mg.mL-1 a 0,6 mg.mL-1. Aatividade antioxidante demonstrou uma correlação linear com a concentração de óleo essencial. Os resultados demonstraram potencial antibacteriano e antioxidante do óleo essencial de Eugenia caryophyllata, constituindo-se uma opção para a formulação de novos produtos alimentícios

Aspectos epidemiológicos do dengue no Município de São Luís, Maranhão, Brasil, 1997-2002 Epidemiological characteristics of dengue in the Municipality of São Luís, Maranhão, Brazil, 1997-2002

Foram notificados 12.008 casos de dengue no período de 1997 a 2002, com picos em 1997 (35,80%) e 1998 (45,80%). A doença predominou na faixa etária de 15-49 anos (72,20%) e na estação chuvosa (83,30%), correlacionando-se positivamente com a precipitação pluviométrica (r = 0,84) e a umidade relativa (r = 0,76), e negativamente com a temperatura (r = -0,78). Não houve diferença significativa (chi2 = 2,319; p > 0,05) no número de casos entre os sexos masculino (49,00%) e feminino (51,00%). Os sete distritos sanitários resultaram positivos: Tirirical (27,00%), Coroadinho (17,00%), Bequimão (16,00%), Cohab (14,00%), Itaqui-Bacanga (11,00%), Centro (8,00%) e Vila Esperança (7,00%). O índice de infestação predial oscilou de 1,01 a 7,15 e o índice de Breteau, de 1,10 a 8,18. Os depósitos mais freqüentes foram: tambor e similares (80,00%), vaso de planta (4,70%), garrafa, lata e plástico (3,60%), pneu (3,30%) e caixa d'água (2,70%); os demais representaram 5,7%. Para Ae. aegyptiforam encontrados 134.631 depósitos positivos, predominando os do tipo B (80,00%), seguidos pelos dos tipos C (4,70%), E (3,60%) e A (3,30%).<br>A total of 12,008 cases of dengue were reported from 1997 to 2002, with peaks in 1997 (35.8%) and 1998 (45.8%). The disease predominated in the 15-49-year age group (72.2%) and during the rainy season (83.3%), showing a positive correlation with the amount of rainfall (r = 0.84) and relative humidity (r = 0.76) and a negative correlation with temperature (r = -0.78). There was no significant difference (chi2 = 2.319; p > 0.05) in the number of cases in males (49%) and females (51%). Dengue was detected in all seven health districts: Tirirical (27%), Coroadinho (17%), Bequimão (16%), Cohab (14%), Itaqui-Bacanga (11%), Centro (8%), and Vila Esperança (7%). The building infestation rate ranged from 1.01 to 7.15, and the Breteau index ranged from 1.10 to 8.18. The most frequent mosquito breeding sites were metal barrels or similar recipients (80.0%), followed by plant vases (4.7%), bottles, cans, and plastics (3.6%), tires (3.3%), water tanks (2.7%), and others (5.7%). In the case of Aedes aegypti, 134,631 positive water deposits were detected, with a predominance of type B (80.0%), followed by types C (4.7%), E (3.6%), and A (3.3%)