Susceptibility of Triatoma sordida Stal, 1859 (Hemiptera: Reduviidae) to alpha-cypermethrin under natural climatic conditions

Abstract:INTRODUCTION:Despite the recommendations by interpretation of resistance ratios obtained in laboratory bioassays, little is known about the actual impact of these results in the effectiveness of vector control activities in the field. In this context, our objective was to determine the mean value of different resistance ratios obtained by laboratory bioassays performed as part of the chemical control strategies of Triatoma sordida in the field.METHODS:Field bioassays were developed in Monte Azul and Coração de Jesus (Southeast, Brazil). In each location, samples were formed with three domestic units treated with alpha-cypermethrin 20.0% (Alfatek (r) 200 SC). One day after spraying, 10 fifth-instar nymphs remained in contact with the surfaces treated (adobe with plaster, adobe without plaster, or wood) with insecticide in plastic cones for 72h. Three cones were exposed inside the intradomicile and the peridomicile. The insects in the control group were exposed to an insecticide-free piece of cardboard. Mortality was measured 72h after removal of the insects from the treated surfaces. The tests were realized in triplicate.RESULTS:Mortality was 100.0% in all locations, except for Monte Azul; Landinho (96.6%) and Coração de Jesus; Barriguda (96.6%).CONCLUSIONS:Although the resistant populations in laboratory tests proved to be susceptible in the field, this observation is not sufficient to suggest that the cut-off points used to justify the resistance ratio should be changed. In this sense, we recommend that laboratory and field bioassays are carried out with a greater number of Triatominae populations to allow more in-depth consideration of the subject.

Basic sanitation, socioeconomic conditions, and degree of risk for the presence and maintenance of malaria in a low-transmission area in the Brazilian Amazon

ABSTRACTINTRODUCTION:This study aimed to evaluate basic sanitation and socioeconomic indicators, reported cases of malaria, and risk of contracting malaria in the Ananindeua municipality, State of Pará.METHODS:Data on basic sanitation and socioeconomic dimensions were taken from the Brazilian Institute of Geography and Statistics [ Instituto Brasileiro de Geografia e Estatística (IBGE)] 2010 census. Epidemiological malaria information was taken from the Epidemiological Malaria Surveillance Information System [ Sistema de Informação de Vigilância Epidemiológica de Malária (SIVEP/Malaria)], between 2003 and 2013 of the Ministry of Health and from the SIVEP/Malaria forms of the municipality's Endemic Diseases Unit for 2,013 cases.RESULTS:Our data do not confirm the correlation among indicators of basic sanitation, socioeconomic conditions, and water supply with malaria cases. Of the 1,557 cases evaluated, most were caused by Plasmodium vivax , with rare cases of Plasmodium falciparum and mixed infections. There were 756 notifications in 2003. The number of reported cases was sharply reduced between 2006 and 2012, but a 142-case outbreak occurred in 2013. Ananindeua municipality's Annual Parasite Index indicated low risk in 2003 and no risk in other years, and the 2,013 cases were predominantly male individuals aged ≥40 years.CONCLUSIONS:Our data confirm the non-endemicity of malaria in the Ananindeua municipality, as the Annual Parasite Indices described for the years 2004-2013 classify it as a risk-free area. However, the 2013 outbreak indicates the need to strengthen prevention, surveillance, and control activities to reduce the risk of new outbreaks and consequent economic and social impacts on the population.

Epidemiological study of hepatitis B and C in a municipality with rural characteristics: Cássia dos Coqueiros, State of São Paulo, Brazil

Abstract: INTRODUCTION: Hepatitis B and C viral infections remain an important cause of global morbidity and mortality. Studies have been conducted in population groups of large cities, leaving gaps in the knowledge regarding the situation in small municipalities. We aimed to measure the prevalence of hepatitis B and C markers and presence of infection-associated factors. METHODS: All inhabitants of Cássia dos Coqueiros aged ≥18 years who agreed to participate in the research were included. We collected blood as well as information via a questionnaire between March 2011 and December 2013. Univariate and multivariate analyses were conducted. RESULTS: Among the 1,001 participants, 41 (4.1%) participants had a serological profile of hepatitis B viral exposure, and only one (0.1%) participant was considered a virus carrier. The frequency of isolated antibody to hepatitis B virus surface antigen (anti-HBs) markers was 17.8% for the overall population. In the multivariate analysis, hepatitis B virus (HBV) infection was associated with age, birth outside the State of São Paulo, history of hepatitis, ≥2 sexual partners in the last 6 months, and tattoos. Four (0.4%) participants had a serological profile of hepatitis C viral exposure. However, after confirmation using viral ribonucleic acid (RNA) evaluation, only one (0.1%) individual remained positive. CONCLUSIONS: The positivity rates for hepatitis B and C were low, despite greater sexual freedom and the recent emergence of illicit drugs, as observed by the health personnel working in Cássia dos Coqueiros.

Emergent and re-emergent parasites in HIV-infected children: immunological and socio-environmental conditions that are involved in the transmission of Giardia spp. and Cryptosporidium spp.

ABSTRACT INTRODUCTION: Emergent and re-emergent waterborne protozoans have become a worldwide public health problem, especially among vulnerable groups. METHODS: This cross-sectional study evaluated 17 HIV-infected children and their families. RESULTS: A high (76.5%) percentage of parasite-infected children was observed, even among children with CD4+ T-cell counts of >200 cells/mm3. Giardia spp., Cryptosporidium spp. and Cyclospora spp. were observed in 41.2% of these children Low income, poor hygiene practices, and co-infection in domestic, peridomestic and scholastic environments were significant sources of these intestinal infections. CONCLUSIONS: Early diagnosis, timely treatment, and socio-educational interventions may improve the health conditions of this vulnerable population.

Factors associated with non-adherence to the treatment of vivax malaria in a rural community from the Brazilian Amazon Basin

Abstract: INTRODUCTION We investigated the association between demographic and behavioral factors and non-adherence to antimalarial therapy. METHODS A demographic questionnaire and 5-item self-reported questionnaire regarding non-adherence were completed by 135 patients after treatment for Plasmodium vivax. RESULTS Treatment interruption, but not demographic factors, was significantly associated with non-adherence to therapy. The likelihood of non-adherence was 5.16 times higher when the patients felt better than when they felt worse. The relative risk of parasitic resurgence was 3.04 times higher in non-adherent patients. CONCLUSIONS Treatment interruption is significantly associated with treatment adherence.

Climatic aspects of the Amazonian Tropical Forest

The purpose of this study is to analyse the climatic aspects of the data collected in a forest site in comparison with conventional data obtained at different sites, such as clearing, rural an urban areas. The results showed that diverse climatic conditions do exist among the sites: the urban site showed higher temperature and lower relative humidity. In addition, evapotranspiration (potential and actual rates) was computed from the forest data set, using the classical Penman-Monteith's equation. The actual evapotranspiration is 30% of the potential value during dry period and seems to be almost constant during the whole year (tipically 2.0 to 2.5 mm day-1).

Perfil antropométrico de mulheres adultas da área urbana e rural no município de Barcelos, AM

De um total de 203 mulheres adultas entrevistadas, foram avaliadas 175 (entre 16 a 73 anos), por meio de medidas antropométricas: peso, altura, prega cutânea tricipital (PCT), circunferência braquial (CB), circunferência muscular (CMB) e Índice de Massa Corpórea (IMC). Das mulheres analisadas, 84,0% (n=147) residiam na zona urbana e 16,0% (n=28) na zona rural. Verificou-se que o peso médio das mulheres não nutrizes residentes na área urbana foi de 54,1 kg; altura de 149,0 cm e o IMC de 24,4 kg/m², enquanto que a PCT, CB e a CMB forneceram valores médios de 19,2 mm, 27,5 cm e 21,5 cm, respectivamente. Na área rural, as mulheres apresentaram um peso médio de 50,4 kg, altura de 148,6 cm, IMC de 23,0 kg/cm² e a PCT, CB e a CMB foram 13,8 mm, 26,4 cm e 22,1 cm, respectivamente. Houve diferença estatisticamente significativa apenas nos valores médios da PCT entre as mulheres procedentes da área urbana e rural (p<0,05). Nas mulheres da área urbana, a ocorrência de baixo peso foi de 6,5%, 28,2% de sobrepeso e 11,3% de obesidade. Nas mulheres da área rural, a prevalência de baixo peso e obesidade foi de 4% e de sobrepeso de 16%. A maioria da população estudada situou-se no limite máximo de normalidade do IMC, e os índices representantes das reservas adiposas (PCT) foram maiores nas mulheres residentes na área urbana.

Preliminary observations on the effect of sudden changes of temperature on survival of young Matrinxã (Brycon cephalus) under laboratory conditions

Matrinxã is a very promising amazonian fish for fish culture in Brazil. This study is aimed at determining the approximate tolerated temperature range in this species. Groups of ten young matrinxã specimens (15.1±0.8 cm average length and 58.3±10.3 g average weight) were subjected to 9 different temperatures for 24 hours without previous acclimation. Fish were transferred from an initial temperature of 27ºC to those ranging from 12 to 39ºC at 3ºC intervals. Both 12ºC and 39ºC temperatures were lethal for this species with 100% mortality rate. Following 2 minutes of exposure to 39ºC fish changed behavior, showing an increase in opercular movements and erratic swimming; mortality reached 100% after 18 minutes. At 12ºC, fish lost equilibrium immediately after exposure and started swimming erratically; after only 4 minutes fish became lethargic and remained immobile on the bottom of the tank. Total mortality was only evident following 24 hours. At 15ºC matrinxã lost equilibrium after 5 to 6 minutes of exposure but mortality was only 20% after 24 hours. Fish tolerated well temperatures ranging from 18 to 36ºC with 100% survival after 24 hours. This preliminary study suggests that temperatures between 18 and 36ºC are the approximate range normally tolerated by this species, although survival at other temperatures may be increased by gradually acclimating fish to the more severe increases or decreases in temperature. In addition, it indicates that matrinxã may be cultivated over a wide geographical area.

Changes in population and land use over time in the Ecuadorian Amazon

This paper draws upon a detailed longitudinal survey of households living on agricultural plots in the northern three provinces of the Ecuadorian Amazon, the principal region of colonization by migrants in Ecuador since the 1970s. Following the discovery of petroleum in 1967 near what has subsequently come to be the provincial capital and largest Amazonian city of Lago Agrio, oil companies built roads to lay pipelines to extract and pump oil across the Andes for export. As a result, for the past 30 years over half of both Ecuador's export earnings and government revenues have come from petroleum extracted from this region. But the roads also facilitated massive spontaneous in-migration of families from origin areas in the Ecuadorian Sierra, characterized by minifundia and rural poverty. This paper is about those migrants and their effects on the Amazonian landscape. We discuss the data collection methodology and summarize key results on settler characteristics and changes in population, land use, land ownership, technology, labor allocation, and living conditions, as well as the relationships between changes in population and changes in land use over time. The population in the study region has been growing rapidly due to both natural population growth (high fertility) and in-migration. This has led to a dramatic process of subdivision and fragmentation of plots in the 1990's, which contrasts with the consolidation of plots that has occurred in most of the mature frontier areas of the Brazilian Amazon. This fragmentation has led to important changes in land tenure and land use, deforestation, cattle raising, labor allocation, and settler welfare.

Diversity of sand flies in domiciliary environment of Santarém, state of Pará, Brazil: species composition and abundance patterns in rural and urban areas

This paper aimed to evaluate the richness, abundance and frequency of sand fly occurrence in rural and urban areas American visceral Leishmaniasis -AVL is endemic in the study area of Santarém municipality, Pará state. Sand flies were collected during 1995-2000, using CDC light traps placed in neighborhoods and rural areas of the municipality. A total of 53.454 individuals and 26 species of sand flies were collected. The most abundant species in both urban and rural environments was Lutzomyia longipalpis, vector of AVL in the area. The highest species richness by capture was in rural area. In all years sampled, the largest number of species of sand fly collected was always in rural areas. The species of sand flies in urban and rural area were similar in 11 species. In the rural area other 11 species were found, a total of 22 species. Shannon-Wiener index ranged from 0.12 to 0.84 at rural areas and 0.08 to 0.34 at urban ones. In general, rural localities showed higher diversity (H') of phlebotomines than urban ones. Individual-based rarefaction curves for each area demonstrated that urban localities had the lowest expected number of phlebotomine species and the richest rural ones reach higher expected values with lower amount of individuals than urban sites. The most frequent species were Lutzomyia longipalpis, Evandromyia carmelinoi and Bichromomyia flaviscutellata.

Daldinia eschscholtzii (Ascomycota, Xylariaceae) isolated from the Brazilian Amazon: taxonomic features and mycelial growth conditions

The Amazon has a high diversity of fungi, including species of the genus Daldinia (Ascomycota, Xylariaceae), which produce secondary metabolites with recognized nematicidal and antimicrobial activity. The ecological role of Daldinia is important, as stromata serve as refuges to many insects and arthropodes, and the fungi contribute to the degradation of vegetable organic matter. The aim of this study was to analyze the taxonomic features and mycelial growth conditions in vitro of a Daldinia specimen collected in the Brazilian Amazon. Morphological and molecular studies of the fungus identified it as D. eschscholtzii. To evaluate mycelial growth, we cultivated the fungus at 20, 25, 30, 35, and 40 °C in malt extract-peptone agar (MEPA), malt extract-peptone (MEP), potato dextrose (PD), and minimum medium (MM). The best mycelial growth occurred at 35 °C, although the greatest amount of biomass was obtained at 25 °C and 30 °C. PD proved to be the best medium for biomass production.

Seasonal and spatial variations in limnological conditions of a floodplain lake (lake Catalão) connected to both the Solimões and Negro Rivers, Central Amazonia

Lakes play an important role in biogeochemical, ecological and hydrological processes in the river-floodplain system. The aim of this study was to evaluate the dynamics of the limnological conditions of Catalão Lake, an Amazon floodplain lake. Thus, some of the main limnological environment variables (O2, temperature, pH, nutrient, electrical conductivity) of the Catalão Lake were analyzed under temporal and spacial scales. The study was conducted between November/2004 and August/2005. Sampling excursion were carried out every three months; one excursion for each of the four different hydrological periods (low water, rising water, high water and falling water). Sampling points were chosen so that it could be obtained a gradient of the distance from Negro River. Limnological profiles in Catalão Lake showed generally acidic to slightly alcaline water, with low levels of dissolved oxygen and low concentrations of soluble reactive phosphorous. The Negro River seems to exert the main influence during the rising water period, while the Solimões River is the principal controlling river during peak water. The Principal Component Analysis (PCA) grouped the seasonal collections by hydrological period, showing the formation of a north-south spatial gradient within the lake in relation to the limnological variables. Multivariate dispersion analysis based on distance-to-centroid method demonstrated an increase in similarity over the course of the hydrological cycle, as the lake was inundated in response to the flood pulse of the main river channels. However, the largest spatial homogeneity in the lake was observed in the epilimnion layer, during the falling water period. The daily analysis of variation indicated an oligomitic pattern during the years in which the lake was permanently connected to the Negro River. Although Catalão Lake receives large quantities of both black water from the Negro River and sediment-filled water from the Solimões River, the physical and chemical characteristics of the lake are more similar to those of the Solimões (várzea lake) than the Negro (blackwater lake).

Trans-cultural aspects of social anxiety disorder and related conditions: a Brazilian case series and a review of international clinical studies

Cross-cultural studies have much to teach clinicians and researchers alike about psychopathology in general and about social anxiety disorder (SAD) in particular. Unfortunately, little is known about the degree and the mechanisms through which cultural environment may influence clinical manifestations of SAD. OBJECTIVE: Our objective was to identify culture-related clinical patterns in SAD and related disorders. METHODS: We described socio-demographic and clinical characteristics of a sample of 62 adult outpatients with SAD seen at a university clinic for anxiety and depressive disorders in Rio de Janeiro, Brazil, and compared them with those reported in clinical samples from North America, Europe, Asia and Oceania identified through a systematic review in Medline, PsychINFO, and LILACS. RESULTS: Our comparison of trans-cultural features of SAD lends partial support to Heimberg's (1997) contention that the majority of socio-demographic features and symptoms of this disorder are relatively independent of geographic and cultural differences. CONCLUSION: Patients with SAD were almost universally characterized by: 1) a predominance of males in clinical samples; 2) early onset of the disorder; 3) high educational attainment; and 4) great frequency of comorbidities.

The results of the Campaign for evaluating sphygmomanometers accuracy and their physical conditions

OBJECTIVE: To evaluate the sphygmomanometers calibration accuracy and the physical conditions of the cuff-bladder, bulb, pump, and valve. METHODS: Sixty hundred and forty five aneroid sphygmomanometers were evaluated, 521 used in private practice and 124 used in hospitals. Aneroid manometers were tested against a properly calibrated mercury manometer and were considered calibrated when the error was <=3mm Hg. The physical conditions of the cuffs-bladder, bulb, pump, and valve were also evaluated. RESULTS: Of the aneroid sphygmomanometers tested, 51% of those used in private practice and 56% of those used in hospitals were found to be not accurately calibrated. Of these, the magnitude of inaccuracy ranged from 4 to 8mm Hg in 70% and 51% of the devices, respectively. The problems found in the cuffs - bladders, bulbs, pumps, and valves of the private practice and hospital devices were bladder damage (34% vs. 21%, respectively), holes/leaks in the bulbs (22% vs. 4%, respectively), and rubber aging (15% vs. 12%, respectively). Of the devices tested, 72% revealed at least one problem interfering with blood pressure measurement accuracy. CONCLUSION: Most of the manometers evaluated, whether used in private practice or in hospitals, were found to be inaccurate and unreliable, and their use may jeopardize the diagnosis and treatment of arterial hypertension.