BackgroundIn Brazil, dengue epidemics erupt sporadically throughout the country and it is unclear if outbreaks may initiate a sustainable transmission cycle. There are few studies evaluating the ability of Brazilian Aedes aegypti populations to transmit dengue virus (DENV). The aim of this study was to compare DENV susceptibility of field-captured Ae. aegypti populations from nine distinct geographic areas of the city of Belo Horizonte in 2009 and 2011. Infection Rate (IR), Vector Competence (VC) and Disseminated Infection Rate (DIR) were determined.MethodsAedes aegypti eggs from each region were collected and reared separately in an insectary. Adult females were experimentally infected with DENV-2 and the virus was detected by qPCR in body and head samples. Data were analyzed with the Statistical Package for the Social Sciences version 17.ResultsIR varied from 40.0% to 82.5% in 2009 and 60.0% to 100.0% in 2011. VC ranged from 25.0% to 77.5% in 2009 and 25.0% to 80.0% in 2011. DIR oscillated from 68.7% to 100.0% in 2009 and 38.4% to 86.8 in 2011. When the results were evaluated by a logistic model using IR as covariate, North, Barreiro, South-Central and Venda Nova showed the strongest association in 2009. In 2011, a similar association was observed for South-Central, Venda Nova, West and Northeast regions. Using VC as covariate, South-Central and Venda Nova showed the most relevant association in 2009. In 2011, South-Central, Venda Nova and Barreiro presented the greatest revelation associations. When DIR data were analyzed by logistic regression models, Pampulha, South-Central, Venda Nova, West, Northeast and East (2009) as well as South-Central, Venda Nova and West (2011) were the districts showing the strongest associations.ConclusionsWe conclude that Ae. aegypti populations from Belo Horizonte exhibit wide variation in vector competence to transmit dengue. Therefore, vector control strategies should be adapted to the available data for each region. Further analysis should be conducted to better understand the reasons for this large variability in vector competence and how these parameters correlate with epidemiological findings in subsequent years.

BackgroundThe study presents estimates for the burden of visceral leishmaniasis (VL) and cutaneous and mucocutaneous leishmaniasis (CML) in Brazil and its 27 federated units using data from the Global Burden of Disease Study (GBD) 2016.MethodologyWe report the incidence, years of life lost (YLL), years lived with disability (YLD), and disability-adjusted life years (DALY) for leishmaniasis in Brazil from 1990 to 2016. The metrics are presented as age-standardized rates per 100,000 inhabitants with their respective uncertainty intervals (95%UI) and relative percentages of change.Principal findingsThe age-standardized incidence rate of leishmaniasis decreased 48.5% from 1990 (71.0, 95%UI 24.3–150.7) to 2016 (36.5, 95%UI 24.7–50.9), whereas the age-standardized DALY increased 83.6% over the studied period from 12.2 (95%UI 7.9–18.8) to 22.4 (95%UI 13.3–36.2). The age-standardized incidence rate and YLL for VL increased by 52.9% and 108% from 1990 to 2016, respectively. Considering CML, the age-standardized incidence rate and YLD decreased by 51% and 31.8% respectively for the same period. For VL, similar profiles for male and female were observed, with YLL and DALY increasing over time; with males presenting slightly higher values. The highest YLL rates were among "under 1-year old" children, which increased 131.2% from 1990 to 2016. Regarding CML, the highest values of YLD and DALY were verified among males, and YLD values showed a similar profile, with rates increasing with age. The VL burden increased in some states in the Northeast and Southeast regions and decreased for CML in some Northern states.ConclusionThe increase of VL burden over the study period might be associated with the difficulties in controlling the disease spread. Information regarding the weight of VL and CML, including the death and disability tolls that they cause, highlights the impact of these neglected diseases on public health and the importance of effective prevention and treatment.

ABSTRACT:Objective: To describe the main metrics on dengue generated by Global Burden of Disease (GBD) Study 2015, for Brazil and its 27 federated units, in the years 2000 and 2015. Methods: The metrics described were: incidence and mortality rates by dengue, standardized by age, years of life lost (YLL), years lived with disability (YLD), and disability-adjusted life years (DALY) (in absolute frequency and age-standardized rates). The estimated metrics were presented with uncertainty intervals (UI 95%) for the years 2000 and 2015, accompanied by the relative percentages of changes. Results: The number of cases increased 232.7% and the number of deaths increased 639.0% between 2000 and 2015 in the country. The incidence rate varied 184.3% and the mortality rate was low, but with an increase of 500.0% in the period evaluated. The YLL, YLD, and DALY rates increased 420.0, 187.2, and 266.1%, respectively. In 2015, DALY was similar among women and men (21.9/100,000). The DALY increased more than double in all the Brazilian federated units. Conclusion:The marked increase in dengue over the years is associated with the introduction and/or circulation of one or more serotypes of the transmitter virus and an increasing proportion of patients affected by the severe form of the disease. Despite the low mortality rate of the disease in comparison between the years of study, the disease contributes to the loss of healthy years of life in Brazil as it affects a large number of people, from all age groups, causing some degree of disability during the infection and deaths, especially, in children.

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Conhecimentos de estudantes sobre Leishmaniose Visceral em escolas públicas de Caxias, Maranhão, BrasilKnowledge of students about visceral leishmaniasis in public schools in Caxias, Maranhão, Brazil

INTRODUCTION: Dengue is a serious public health problem worldwide, with cases reported annually in tropical and subtropical regions. Aedes aegypti (Linnaeus, 1762), the main vector of dengue, is a domiciliary species with high dispersal and survival capacities and can use various artificial containers as breeding sites. We assessed potential container breeding sites of A. aegypti in the municipality of Caxias, Maranhão, Brazil. METHODS: In the initial phase, we analyzed 900 properties in 3 neighborhoods during the dry and rainy seasons (August-October 2005 and February-April 2006, respectively). During the second sampling period, September 2006-August 2007, we used 5 assessment cycles for 300 properties in a single neighborhood. RESULTS: During the dry and rainy seasons, water-storage containers comprised 55.7% (n = 1,970) and 48.5% (n = 1,836) of the total containers inspected, and showed the highest productivity of immature A. aegypti; we found 23.7 and 106.1 individuals/container, respectively, in peridomicile sites. In intradomicile sites, water-storage containers were also the most important breeding sites with 86.4% (n = 973) and 85.6% (n = 900) of all containers and a mean of 7.9 and 108.3 individuals/container in the dry and rainy seaso-October 2006 (1,342). The highest number of positives (70) was recorded in May, mostly (94%) in storage containers. CONCLUSIONS: Storage containers are the principal and most productive A. aegypti breeding sites and are a major contributing factor to the maintenance of this vector in Caxias.

Brazil reported the majority of the dengue cases in Americas during the last two decades, where the occurrence of human dengue cases is exclusively attributed to the Aedes (Stegomyia) aegypti (Linnaeus). Nowadays, other recognized Dengue virus (DENV) vector in Asian countries, Aedes (Stegomyia) albopictus (Skuse), has been detected in more than half of the 5565 Brazilian municipalities. Therefore, the aim of the present study was to investigate the presence of, and determine the Ae. albopictus’ dynamics influenced by spatiotemporal characteristics in a dengue-endemic risk city of Belo Horizonte, Minas Gerais State’s capital. Aedes albopictus were collected across four consecutive DENV transmission seasons from 2010 to 2014. These mosquitoes were caught in three selected districts, which had been reported in the previous ten years as having high mosquito densities and an elevated concentration of human dengue cases during epidemic seasons. All field-caught Ae. albopictus was individually processed by real-time RT-PCR, to research the DENV presence. The third season (p < 0.05) and the Pampulha district (p < 0.05) had the highest proportions of field-caught Ae. albopictus, respectively. The second season had the highest proportion of DENV-infected field-caught females (p < 0.05), but there was no difference among the proportions of DENV-infected Ae. albopictus when comparing the collection in the three districts (p = 0.98). Minimum (p = 0.004) and maximum (p < 0.0001) temperature were correlated with the field-caught Ae. albopictus in four different periods and districts. In the generalized linear model of Poisson, the field-caught DENV-infected Ae. albopictus (p = 0.005), East district (p = 0.003), minimum temperature (p < 0.0001) and relative humidity (p = 0.001) remained associated with the total number of human dengue cases. Our study demonstrated that the number of field-caught DENV-infected Ae. albopictus was inversed correlated with the number of human dengue cases. Our study raises the possibility that the DENV circulating in mosquitoes Ae. albopictus is happening in non-epidemic periods, showing that this species may be keeping only the presence of the virus in nature. Further long-term studies are necessary to better understand the role of Ae. albopictus in DENV transmission and or its vectorial competence in Belo Horizonte and in other endemic cities in Brazil and in the New World countries.

This study describes a survey (n=700) carried out in 14 elementary schools in the municipality of Caxias, State of Maranhão, Brazil. The survey was conducted between July and December 2007 in schools from seven neighborhoods on the outskirts of the western part of the municipality, where for the past three years high densities of immature Aedes aegypti mosquitoes have been recorded. The students' knowledge of dengue, its vector, and disease prevention was evaluated by targeted questionnaires. The students with the most comprehensive knowledge were found in schools in the Trizidela neighborhood, which has better social and urban conditions than the other neighborhoods. Moreover, educational campaigns are necessary to reinforce behavioral changes of the population, because the existence of breeding sites in the areas examined was mentioned, especially in the Tamarineiro neighborhood. The survey can be used to assist with new educational activities of local teams working with dengue control.