Preparation and characterization of high density polyethylene and residual fibre of Attalea funifera Mart (piacava) composites

International Nuclear Information System (INIS)

Agrela, Sara P.; Guimaraes, Danilo H.; Jose, Nadia M.; Carvalho, Gleidson G.P.; Carvalho, Ricardo F.

2009-01-01

The use of natural fiber reinforcement thermoplastic polymer is continuously increasing. This fact is manly due to its advantages as low cost, availability, recyclability, low energy demand and then environmental appeal if compared to synthetics fibers. The composites were prepared in different fiber volume ratios (5%, 10% and 20%) mixed with high density polyethylene (HDPE) and heated at 190 deg C. Thermogravimetric analysis and differential scanning calorimetry were used to investigate thermal stability. The composites structure was characterized by Fourier Transform Infrared spectroscopy, X-ray diffractometry. Fiber and residue of piassava (Attalea funifera Mart) chemical composition were determined by Van Soest Method. The results indicate that thermo stability of the composites of HDPE prepared with fiber volume ratios up to 20% is only slightly lowered. (author)

Preparation and characterization of high density polyethylene and residual fibre of Attalea funifera Mart (piacava) composites; Preparacao e caracterizacao de compositos de polietileno de alta densidade com residuos de fibras de piacava da especie Attalea funifera Mart

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Agrela, Sara P.; Guimaraes, Danilo H.; Jose, Nadia M., E-mail: saraagrela@hotmail.co [Universidade Federal da Bahia (GECIM/IQ/UFBA), Salvador, BA (Brazil). Inst. de Quimica. Grupo de Energia e Ciencias dos Materiais; Carvalho, Gleidson G.P. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Escola de Medicina Veterinaria. Dept. de Producao Animal; Carvalho, Ricardo F. [Universidade Federal da Bahia (EP/UFBA), Salvador, BA (Brazil). Escola Politecnica. Curso de Mestrado em Engenharia Ambiental Urbana

2009-07-01

The use of natural fiber reinforcement thermoplastic polymer is continuously increasing. This fact is manly due to its advantages as low cost, availability, recyclability, low energy demand and then environmental appeal if compared to synthetics fibers. The composites were prepared in different fiber volume ratios (5%, 10% and 20%) mixed with high density polyethylene (HDPE) and heated at 190 deg C. Thermogravimetric analysis and differential scanning calorimetry were used to investigate thermal stability. The composites structure was characterized by Fourier Transform Infrared spectroscopy, X-ray diffractometry. Fiber and residue of piassava (Attalea funifera Mart) chemical composition were determined by Van Soest Method. The results indicate that thermo stability of the composites of HDPE prepared with fiber volume ratios up to 20% is only slightly lowered. (author)

The importance of forest disturbance for the recruitment of the large arborescent palm Attalea maripa in a seasonally-dry Amazonian forest

OpenAIRE

Salm,Rodolfo

2005-01-01

The hypothesis that forest disturbance is important for the recruitment of the large arborescent palms Attalea maripa was tested with a natural experiment in the Pinkaití site (7º 46'S; 51º 57'W), a seasonally-dry Amazonian forest. A 8,000 m long trail, that crosses, in its lower half, an open forest along the Pinkaití stream bottomlands and, on its upper half, a dense forest on a hill, was divided in 160 0.15 ha (50x30 m) sampling units. At each unit, adult palms were counted and percentage ...

In vitro cytotoxic activity of Brazilian Middle West plant extracts

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Talal Suleiman Mahmoud

2011-06-01

Full Text Available Cytotoxic activity of eight plant extracts, native from the Mid-West of Brazil comprising Cerrado, Pantanal and semideciduous forest, was evaluated for MDA-MB-435, SF-295, and HCT-8 cancer cell strains. A single 100 µg.mL-1 dose of each extract was employed with 72 h of incubation for all tests. Doxorubicin (1 µg.mL-1 was used as the positive control and the MTT method was used to detect the activity. Cytotoxicity of distinct polarities was observed in thirty extracts (46%, from different parts of the following species: Tabebuia heptaphylla (Vell. Toledo, Bignoniaceae, Tapirira guianensis Aubl., Anacardiaceae, Myracrodruon urundeuva Allemão, Anacardiaceae, Schinus terebinthifolius Raddi, Anacardiaceae, Gomphrena elegans Mart., Amaranthaceae, Attalea phalerata Mart. ex Spreng., Arecaceae, Eugenia uniflora L., Myrtaceae, and Annona dioica A. St.-Hil., Annonaceae. Extracts of at least two tested cell strains were considered to be highly active since their inhibition rate was over 75%.

Avaliação da toxicidade aguda do extrato aquoso do pó do mesocarpo de Orbignya phalerata Mart (babaçu)

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dos Santos e Silva, Ana Paula; de Sousa, Geane Felix; Mendes de Freitas, Rivelilson; Cunha Nunes, Lívio César

2012-01-01

Objetivos: os efeitos da administração aguda oral do extrato aquoso do pó obtido do mesocarpo de Orbignya phalerata Mart foram investigados sobre parâmetros bioquímicos e hematológicos em camundongos Swiss machos. Métodos: os animais (n= 5-7/grupo) foram tratados por via oral com as doses de 1, 2 e 3 g/kg de peso corporal, observados durante 24 h e em seguida foi feita a coleta do sangue para avaliação dos parâmetros bioquímicos e hematológicos. Resultados: o tratamento com extrato aquoso do ...

Características fisicoquímicas del aceite del endospermo de la Palma Yagua (Attalea cryptanther

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Linares, Oscar

2006-09-01

Full Text Available In this research, the physicochemical characteristics of the yagua palm (Attalea cryptanther endospermus oil were evaluated. Seeds of mature fruits from Santa Ana hill, Canoabo, Bejuma municipality, Carabobo state-Venezuela, harvested in November 2003, were decorticated and the endospermus was transformed to meal by means of grinding. The oil from meal was extracted with n-hexane using Soxhlet equipment. Yagua endospermus crude oil showed the following characteristics: iodine index 13.77 cg I2/g; refraction index 1.4441 at 60 ºC; saponification value 233 mg KOH/g; peroxide value 0.20 meq O2/kg; unsaponifiable matter 0.97 %; AOM stability 31 h; solid fat content 54 % at 10 ºC and 10 % at 20 ºC; Lovibond color: R 3.2 and Y 1.3. The major fatty acids were lauric acid (58 % and miristic acid (16.5 %.Yagua endospermus is an alternative oleaginousEl objetivo de esta investigación fue caracterizar físicoquímicamente el aceite de la palma Yagua (Attalea cryptanther. El endospermo de frutos maduros procedentes del cerro Santa Ana, Canoabo, municipio Bejuma, estado Carabobo Venezuela, pertenecientes a la cosecha Noviembre 2003, fueron transformados en harina mediante molienda. Una vez obtenida la harina se procedió a la extracción del aceite mediante un equipo Soxhlet utilizando como solvente n-Hexano. El aceite crudo extraído fue caracterizado mediante normas COVENIN y AOCS. Se determinaron valores de índice de yodo de 13,77 cg I2/g, índice de refracción 1,4441 a 60 °C, índice de saponificación 233mg KOH/g, índice de peroxido 0,20 meq O2/Kg, materia insaponificable 0,97%, estabilidad AOM (31 horas, contenido de grasa sólida (54% a 10 °C y 10% a 20 °C, color (R: 3,2- A: 1,3-A: 0. Los ácidos grasos mayoritarios encontrados fueron el ácido laurico (58% y el ácido miristico (16,5%. El endospermo evaluado es una alternativa como materia prima para la obtención de aceite ya que presenta características similares al aceite de coco y

Schinus terebinthifolius raddi (Aroeira) and Orbignya phalerata mart. (Babassu) effect in cecorrahphy healing in rats.

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Scheibe, Christian Lamar; Ribas-Filho, Jurandir Marcondes; Czeczko, Nicolau Gregori; Malafaia, Osvaldo; Barboza, Luiz Eduardo Durães; Ribas, Fernanda Marcondes; Wendler, Eduardo; Torres, Orlando; Lovato, Fernanda Christo; Scapini, João Guilherme Seifert

2016-06-01

To evaluate the effect of Schinus terebinthifolius Raddi (aroeira) and Orbignya phalerata Mart. (babassu) in the healing process of cecorrhaphy in rats. : Fifty four rats were used, distributed into three groups randomly: aroeira, babassu and control, which were divided into three subgroups (six animals) according to the time of the deaths (7, 14, 21 days). All underwent the same surgical procedure, cecotomy and cecorrhaphy. The animals in group aroeira and babassu received daily dose of 100 mg/kg of hydroalcoholic extract and 50 mg/kg of aquous extract respectively, by gavage. The control group received only saline solution. The parameters evaluated were: macroscopic changes, ,resistance test to air insufflations and histological changes. : All animals showed good healing without infection. All groups presented adhesions between cecum and neighboring organs. The resistance test insufflating of atmospheric air showed progressive increase of pressure according to the days in the aroeira group, and decrease in babassu group, without significant difference. Microscopy showed significant difference in the polymorphonuclear, hyperemia, angiogenesis, fibroblast proliferation and collagen histological variables in the 14th day. : Hydroalcoholic extract of aroeira and the aqueous extract of babassu favored the healing process in cecorrhaphy in rats.

Soil microbial biomass in an agroforestry system of Northeast Brazil

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Rosane C. Rodrigues

2015-01-01

Full Text Available Agroforestry systems (AFS are considered alternative land use options to help prevent soil degradation and improve soil microbial biomass and organic C status. However, it is unclear how different densities of babassu palm [Attalea speciosa (syn. Orbignya phalerata], which is an important tree in Northeast Brazil, affect the soil microbial biomass. We investigated the soil microbial biomass C and activity under AFS with different densities of babassu palm associated with Brachiaria brizantha grass. Soil microbial biomass C (MBC, soil microbial biomass N (MBN, MBC:total organic C ratio, fluorescein diacetate hydrolysis and dehydrogenase activity showed highest values in plots with high density of babassu palm. On the other hand, the respiratory quotient (qCO2 was significantly greater in plots without babassu palm. Brachiaria brizantha in monoculture may promote C losses from the soil, but AFS with high density of babassu palm may increase the potential of soils to accumulate C.Keywords: Enzyme activity, tropical soil, babassu palm, silvopastoral system, soil quality.DOI: 10.17138/TGFT(341-48

[Analysis of healing in the Alba Linea with the use of Orbignya phalerata (babassu) water extract. Controlled study in rats].

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Brito Filho, Sebastião Barreto de; Matias, Jorge Eduardo F; Stahlke Júnior, Henrique Jorge; Torres, Orlando Jorge Martins; Timi, Jorge Rufino Ribas; Tenório, Sérgio Bernardo; Tâmbara, Elizabeth Milla; Carstens, Angelo G; Campos, Richard Vieira; Myamoto, Márcio

2006-01-01

The babassu mesocarp (Orbignya phalerata) has been used in experimental research studies focused on its antiinflammatory action. In state of Maranhão--Brazil it is widely used not only as food, but also as popular medicine in wound healing process. To evaluate the action of Orbignya phalerata extract in macroscopic, histologic and tensiometric aspects in the healing process of median laparotomy in rats. Forty male adult Wistar rats were submitted to an incision in the alba linea, sutured back in one plan with separated stitches of polypropylene 5-0. After regular procedure, the animals were divided into two groups of 20 rats each. To the group named control an intraperitoneal, dose of 1.0 ml of saline solution per kilogram of body weight was done. To the experimental group, the same thing was also done, but instead of saline solution it was injected water solution of babassu, in a dose of 50 mg/kg. The animals were observed in the following days. All of them were killed within a three and seven day post-operative period schedule, and then a histological and tensiometric analysis was carried out. On macroscopic examination no relevant adherence, between the alba linea and the abdominal organs in the study groups, was found. Histological evaluation presented marginal significant effects (p=0.86) to acute inflammation and significant effects (p=0.003) to giant cell reaction in both control and experimental three days groups. Significant difference was observed to acute inflammation in both seven days control and experimental groups. In the intragroup analysis (control three and seven) some marginal significant effect was in relationship to acute and chronic inflammation. In the inter-experimental groups analysis, only the giant cell reactions (0.002) and colagenization had significant results. The tensiometric evaluation showed in the seven day experimental group more resistance then others. The macroscopic and histological evaluation didn't show any significant

Integrating the Public in Mosquito Management: Active Education by Community Peers Can Lead to Significant Reduction in Peridomestic Container Mosquito Habitats

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Healy, Kristen; Hamilton, George; Crepeau, Taryn; Healy, Sean; Unlu, Isik; Farajollahi, Ary; Fonseca, Dina M.

2014-01-01

Mosquito species that utilize peridomestic containers for immature development are commonly aggressive human biters, and because they often reach high abundance, create significant nuisance. One of these species, the Asian tiger mosquito Aedes albopictus, is an important vector of emerging infectious diseases, such as dengue, chikungunya, and Zika fevers. Integrated mosquito management (IMM) of Ae. albopictus is particularly difficult because it requires access to private yards in urban and suburban residences. It has become apparent that in the event of a public health concern due to this species, homeowners will have to be active participants in the control process by reducing mosquito habitats in their properties, an activity known as source reduction. However, limited attempts at quantifying the effect of source reduction by homeowners have had mixed results. Of note, many mosquito control programs in the US have some form of education outreach, however the primary approach is often passive focusing on the distribution of education materials as flyers. In 2010, we evaluated the use of active community peer education in a source reduction program, using AmeriCorps volunteers. The volunteers were mobilized over a 4-week period, in two areas with approximately 1,000 residences each in urban Mercer and suburban Monmouth counties in New Jersey, USA. The volunteers were first provided training on peridomestic mosquitoes and on basic approaches to reducing the number of container habitats for mosquito larvae in backyards. Within the two treatment areas the volunteers successfully engaged 758 separate homes. Repeated measures analysis of variance showed a significant reduction in container habitats in the sites where the volunteers actively engaged the community compared to untreated control areas in both counties. Our results suggest that active education using community peer educators can be an effective means of source reduction, and a critical tool in the arsenal

Palmeras usadas por los indígenas Asháninkas en la Amazonía Peruana

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Joanna Sosnowska

2011-05-01

Full Text Available El presente artículo muestra el conocimiento e importancia de las palmeras en la vida de los nativos Asháninkas. Presentamos una descripción cualitativa y cuantitativa de 32 entrevistas, obtenidos durante la visita a siete comunidades nativas ubicadas en los márgenes de los ríos Perené y Tambo en el departamento Junín, Perú. Registramos 15 especies de palmeras usadas por los Asháninkas, agrupadas bajo cinco categorías de uso: alimenticio, construcción, herramienta, ornamental y medicinal. Las especies con usos más amplios son: Attalea phalerata, Bactris gasipaes, Oenocarpus bataua y Socratea exorhiza. Las partes de las palmeras más utilizadas son los frutos, principalmente gracias a su valor comestible. La cercanía de las comunidades Asháninkas del valle del Perené a ciudades, influirían en un cambio en el tipo de vida tradicional, donde las palmeras son los más importantes recursos naturales utilizados por ellos. Sin embargo, en las comunidades del valle Tambo la vida tradicional, el conocimiento y practica en el uso de las palmeras esta aún vital

Detection of Coxiella burnetii DNA in Peridomestic and Wild Animals and Ticks in an Endemic Region (Canary Islands, Spain).

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Bolaños-Rivero, Margarita; Carranza-Rodríguez, Cristina; Rodríguez, Noe F; Gutiérrez, Carlos; Pérez-Arellano, José-Luis

2017-09-01

Coxiella burnetii, the etiological agent of human Q fever, can infect mammals, birds, and arthropods. The Canary Islands (Spain) are considered an endemic territory, with a high prevalence in both humans and livestock. Nonetheless, there is no epidemiological information about the wild and peridomestic cycles of C. burnetii. Tissue samples from rodents on farms (100) and wild rabbits (129) were collected and assessed by PCR to detect C. burnetii DNA. In parallel, ticks were also collected from vegetation (1169), livestock (335), domestic dogs (169), and wild animals (65). Globally, eight rodents (8%) and two rabbits (1.5%) were found to be positive, with the spleen being the most affected organ. Tick species identified were Hyalomma lusitanicum, Rhipicephalus turanicus, Rhipicephalus sanguineus, and Rhipicephalus pusillus. Hyalomma lusitanicum (80%) was the main species identified in vegetation, livestock, and wild animals, whereas Rhipicephalus sanguineus was the most prevalent in domestic dogs. Overall, C. burnetii DNA was detected in 6.1% of the processed ticks, distributed between those removed from livestock (11.3%), domestic dogs (6.9%), and from wild animals (6%). Ticks from vegetation were all negative. Results suggest that, in the Canary Islands, C. burnetii develops in a peridomestic rather than a wild cycle.

Experimental Challenge of a Peridomestic Avian Species, European Starlings ( Sturnus vulgaris ), with Novel Influenza A H7N9 Virus from China.

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Hall, Jeffrey S; Ip, Hon S; TeSlaa, Joshua L; Nashold, Sean W; Dusek, Robert J

2016-07-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings ( Sturnus vulgaris ) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Experimental challenge of a peridomestic avian species, European Starlings (Sturnus vulgaris), with novel Influenza A H7N9 virus from China

Science.gov (United States)

Hall, Jeffrey S.; Ip, Hon S.; Teslaa, Joshua L.; Nashold, Sean W.; Dusek, Robert

2016-01-01

In 2013 a novel avian influenza H7N9 virus was isolated from several critically ill patients in China, and infection with this virus has since caused more than 200 human deaths. Live poultry markets are the likely locations of virus exposure to humans. Peridomestic avian species also may play important roles in the transmission and maintenance of H7N9 at live poultry markets. We experimentally challenged wild European Starlings (Sturnus vulgaris) with the novel H7N9 virus and measured virus excretion, clinical signs, and infectious dose. We found that European Starlings can be infected with this virus when inoculated with relatively high doses, and we predict that infected birds excrete sufficient amounts of virus to transmit to other birds, including domestic chickens. Infected European Starlings showed no clinical signs or mortality after infection with H7N9. This abundant peridomestic bird may be a source of the novel H7N9 virus in live poultry markets and may have roles in virus transmission to poultry and humans.

Ethnobotany of babassu palm ( Attalea speciosa Mart. in the Tucuruí Lake Protected Areas Mosaic - eastern Amazon

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Fábio Ribeiro Araújo

2016-01-01

Full Text Available ABSTRACT Documenting the ethnobotanical knowledge of populations living in protected areas is important both for science and for the effective conservation of these areas, as it can help to clarify the level of dependency that human communities have on local plant resources. Babassu (Attalea speciosa, Arecaceae is one of the most important non-timber forest resources of rural communities in the Amazon. We explored the ethnobotanical knowledge and uses of babassu by riverine populations inhabiting the Tucuruí Lake Protected Areas Mosaic in the eastern Amazon, by examining the diversity, purposes and descriptions of its uses and aspects of its extraction. Data were collected in 2010 and 2014 from 193 families. A total of 1,226 use records were cited representing 60 different uses. Records were classified into nine use-categories; utensils and tools was the most important category, followed by construction and human food. The use with the greatest purpose consensus value among the informants was thatch. Babassu proved to be an important resource for the livelihood of the local communities in providing shelter, food and reliable energy. Most informants lacked knowledge about sustainable practices and management of this resource.

Análise da cicatrização na Linha Alba com uso de extrato aquoso de Orbignya phalerata (babaçu: estudo controlado em ratos Analysis of healing in the Alba Linea with the use of Orbignya phalerata (babassu water extract: controlled study in rats

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Sebastião Barreto de Brito Filho

2006-01-01

Full Text Available INTRODUÇÃO: O mesocarpo do babaçu (Orbignya phalerata tem sido utilizado em estudos experimentais para verificar a sua ação antiinflamatória. No Maranhão, é muito utilizado como alimento e como remédio popular para cicatrização de ferimentos. OBJETIVO: Avaliar macroscópica, histológica e tensiometricamente, a ação do extrato de Orbygnia phalerata no processo de cicatrização de laparotomias medianas em ratos. MÉTODOS: Quarenta ratos da linhagem Wistar, adultos, machos, foram utilizados em procedimento experimental que consistiu em uma incisão na linha alba e síntese em plano único com pontos separados de fio de polipropileno 5-0. Após esse procedimento comum, os animais foram distribuídos em dois grupos de 20. Ao grupo chamado controle, foi utilizado injeção intraperitoneal, em dose única de 1mL de soro fisiológico para cada quilo de peso. Ao grupo experimento, utilizou-se solução aquosa de babaçu na dose de 50 mg por quilo de peso. Os animais foram acompanhados e mortos após três e sete dias, procedendo-se, a seguir, à análise tensiométrica e histológica. RESULTADOS: O exame macroscópico não mostrou presença de aderências importantes entre a linha alba e os órgãos intra-abdominais nos grupos de estudo. A avaliação histológica mostrou efeito marginalmente significativo (p=0,086 para inflamação aguda nos grupos controle e experimento de três dias e efeito significativo (p=0,003 para a reação gigantocelular (p=0,003. Diferença significativa (p-=0,023 foi observada para inflamação aguda no grupos controle experimento de sete dias. Na análise intra-grupo (controle três e sete, foi observado efeito marginalmente significativo (p=0,094 e p=0,05 respectivamente para as variáveis inflamação aguda e crônica. Na análise somente entre os grupos experimentos, as variáveis reação gigantocelular (0,002 e colagenização (0,016 apresentaram resultado significativo. A avaliação tensiom

Distribution and Diversity of Pathogenic Leptospira Species in Peri-domestic Surface Waters from South Central Chile.

Science.gov (United States)

Mason, Meghan R; Encina, Carolina; Sreevatsan, Srinand; Muñoz-Zanzi, Claudia

2016-08-01

Leptospirosis is a neglected zoonosis affecting animals and humans caused by infection with Leptospira. The bacteria can survive outside of hosts for long periods of time in soil and water. While identification of Leptospira species from human cases and animal reservoirs are increasingly reported, little is known about the diversity of pathogenic Leptospira species in the environment and how surveillance of the environment might be used for monitoring and controlling disease. Water samples (n = 104) were collected from the peri-domestic environment of 422 households from farms, rural villages, and urban slums participating in a broader study on the eco-epidemiology of leptospirosis in the Los Rios Region, Chile, between October 2010 and April 2012. The secY region of samples, previously detected as pathogenic Leptospira by PCR, was amplified and sequenced. Sequences were aligned using ClustalW in MEGA, and a minimum spanning tree was created in PHYLOViZ using the goeBURST algorithm to assess sequence similarity. Sequences from four clinical isolates, 17 rodents, and 20 reference strains were also included in the analysis. Overall, water samples contained L. interrogans, L. kirschneri, and L. weilii, with descending frequency. All species were found in each community type. The distribution of the species differed by the season in which the water samples were obtained. There was no evidence that community-level prevalence of Leptospira in dogs, rodents, or livestock influenced pathogen diversity in the water samples. This study reports the presence of pathogenic Leptospira in the peri-domestic environment of households in three community types and the differences in Leptospira diversity at the community level. Systematic environmental surveillance of Leptospira can be used for detecting changes in pathogen diversity and to identify and monitor contaminated areas where an increased risk of human infection exists.

Distribution and Diversity of Pathogenic Leptospira Species in Peri-domestic Surface Waters from South Central Chile.

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Meghan R Mason

2016-08-01

Full Text Available Leptospirosis is a neglected zoonosis affecting animals and humans caused by infection with Leptospira. The bacteria can survive outside of hosts for long periods of time in soil and water. While identification of Leptospira species from human cases and animal reservoirs are increasingly reported, little is known about the diversity of pathogenic Leptospira species in the environment and how surveillance of the environment might be used for monitoring and controlling disease.Water samples (n = 104 were collected from the peri-domestic environment of 422 households from farms, rural villages, and urban slums participating in a broader study on the eco-epidemiology of leptospirosis in the Los Rios Region, Chile, between October 2010 and April 2012. The secY region of samples, previously detected as pathogenic Leptospira by PCR, was amplified and sequenced. Sequences were aligned using ClustalW in MEGA, and a minimum spanning tree was created in PHYLOViZ using the goeBURST algorithm to assess sequence similarity. Sequences from four clinical isolates, 17 rodents, and 20 reference strains were also included in the analysis. Overall, water samples contained L. interrogans, L. kirschneri, and L. weilii, with descending frequency. All species were found in each community type. The distribution of the species differed by the season in which the water samples were obtained. There was no evidence that community-level prevalence of Leptospira in dogs, rodents, or livestock influenced pathogen diversity in the water samples.This study reports the presence of pathogenic Leptospira in the peri-domestic environment of households in three community types and the differences in Leptospira diversity at the community level. Systematic environmental surveillance of Leptospira can be used for detecting changes in pathogen diversity and to identify and monitor contaminated areas where an increased risk of human infection exists.

Conhecimento e uso do ouricuri (Syagrus coronata e do babaçu (Orbignya phalerata em Buíque, PE, Brasil Knowledge and use of ouricuri (Syagrus coronata and babaçu (Orbignya phalerata in Buíque, Pernambuco State, Brazil

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Márcio Ulisses de Lima Rufino

2008-12-01

Full Text Available O Nordeste do Brasil abriga 80 espécies de palmeiras nativas, com baixo endemismo (27,5%, algumas delas ameaçadas pelas alterações destrutivas do habitat natural, associadas à exploração desordenada. Investigou-se do ponto de vista etnobotânico a importância do ouricuri (Syagrus coronata e do babaçu (Orbignya phalerata em uma comunidade estabelecida junto ao Parque Nacional Vale do Catimbau, município de Buíque, Pernambuco. A importância atribuída pelo povo local para essas espécies foi analisada sob os seguintes aspectos: número de usos, número de informantes que faziam uso de seus produtos diretos ou indiretos; grau de consenso entre os informantes referentes aos usos relatados. Os dados foram obtidos através de entrevistas semi-estruturadas (60 informantes e de índices baseados em técnicas de consenso do informante. Foram citadas sete categorias de uso: alimento do homem; alimento de animais domésticos; alimento de animais silvestres; construção; artesanato; combustível; medicinal. Apesar da diversidade de usos (Sc = 33; Oph = 25, a importância das duas espécies está relacionada predominantemente ao aproveitamento da amêndoa, como mostram os índices de valor para frutos (Sc = 0,48; Oph = 0,56. Analisando a contribuição de cada espécie para o uso total, o ouricuri apresentou maior valor (8,58 em relação ao babaçu (6,31. Sinais de um processo de erosão do conhecimento foram observados, com vários usos apontados como não mais praticados na comunidade, particularmente os associados ao artesanato.The palm tree flora of Brazilian Northeast includes 80 native species, with a low level of endemism (27.5%, some of them threatened by the destructive alterations of the natural habitat, associated to disordered exploration. This study investigated the importance of the ouricuri (Syagrus coronata and the babaçu (Orbignya phalerata in a community established near the Catimbau Valley National Park, Buíque municipality

Desenvolvimento e projeto de colhedora de babaçu (Orbignya phalerata Mart. para agricultura familiar nas regiões de matas de transição da Amazônia Design and development of babaçu (Orbignya phalerata Mart. harvest for small farms in areas of forests transition of the Amazon

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Daniel Albiero

2011-03-01

Full Text Available O babaçu (Orbignya phalerata é uma típica palmeira das matas de transição dos ecossistemas Amazônia/Cerrado e Amazônia/Caatinga, sendo de grande importância econômica, social e ambiental nestas regiões. Os produtos advindos dos babaçuais possibilitam renda para uma das camadas mais pobres da região amazônica e um dos entraves para a obtenção eficiente destes produtos é a colheita dos cocos de babaçu, que atualmente se faz no sistema extrativista. O objetivo deste trabalho foi realizar o desenvolvimento e projeto de uma colhedora de babaçu adaptável ao ambiente de trabalho da agricultura familiar e as características das matas de transição amazônicas. Para tal foram realizados estudos de literatura que nortearam as decisões e simplificações de projeto, assim como foram realizados os cálculos e desenhos da nova colhedora. O projeto foi realizado através de ferramentas de engenharia que apresentaram como resultados o memorial de cálculo que descreve o caminho técnico para o dimensionamento dos elementos constituintes da colhedora e a partir destes os desenhos detalhados dos elementos da nova máquina. Pelos desenhos detalhados suas considerações e decisões concluí-se que a colhedora de babaçu apresenta-se passível de ser construída com materiais nacionais de baixo custo, além de fácil operação, manutenção e com mínimo efeito sobre os babaçuais naturais.The babaçu (Orbignya phalerata is a typical palm of transition forests of Amazon/Savana and Amazon/Caatinga econsystems; it is very important economically, socially and environmentally in this region. Products derived from babaçu provide income for the poor of these regions. One of the problems for obtaining this product efficiently is the extractivist system of harvesting. The objective of this work is to set up a self-propelling project of babaçu harvesting, for family farmers of the Amazonian transition forest region, which would not interfere in

Nematocytes: Discovery and characterization of a novel anculeate hemocyte in Drosophila falleni and Drosophila phalerata.

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Julianna Bozler

Full Text Available Immune challenges, such as parasitism, can be so pervasive and deleterious that they constitute an existential threat to a species' survival. In response to these ecological pressures, organisms have developed a wide array of novel behavioral, cellular, and molecular adaptations. Research into these immune defenses in model systems has resulted in a revolutionary understanding of evolution and functional biology. As the field has expanded beyond the limited number of model organisms our appreciation of evolutionary innovation and unique biology has widened as well. With this in mind, we have surveyed the hemolymph of several non-model species of Drosophila. Here we identify and describe a novel hemocyte, type-II nematocytes, found in larval stages of numerous Drosophila species. Examined in detail in Drosophila falleni and Drosophila phalerata, we find that these remarkable cells are distinct from previously described hemocytes due to their anucleate state (lacking a nucleus and unusual morphology. Type-II nematocytes are long, narrow cells with spindle-like projections extending from a cell body with high densities of mitochondria and microtubules, and exhibit the ability to synthesize proteins. These properties are unexpected for enucleated cells, and together with our additional characterization, we demonstrate that these type-II nematocytes represent a biological novelty. Surprisingly, despite the absence of a nucleus, we observe through live cell imaging that these cells remain motile with a highly dynamic cellular shape. Furthermore, these cells demonstrate the ability to form multicellular structures, which we suggest may be a component of the innate immune response to macro-parasites. In addition, live cell imaging points to a large nucleated hemocyte, type-I nematocyte, as the progenitor cell, leading to enucleation through a budding or asymmetrical division process rather than nuclear ejection: This study is the first to report such a

Population structure and fruit availability of the babassu palm ( Attalea speciosa Mart. ex Spreng in human-dominated landscapes of the Northeast Region of Brazil

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Juliana Loureiro Almeida Campos

Full Text Available ABSTRACT We studied the population structure and fruit availability of the babassu palm, Attalea speciosa, in three human-dominated landscapes located near a rural community in the region of Araripe, in the Northeast Region of Brazil, that were under intense fruit harvest. Fifty 10 x 10 m plots were randomly established in each of the three landscapes, and all individuals of A. speciosa within the plots were classified as seedlings, juveniles or adults, with the height of all adult individuals being measured. An additional 20 individuals were marked in each landscape, and the number of total bunches, fruits per bunch and bunches per palm tree were recorded. The populations of A. speciosa in the three landscapes exhibited an inverted J-shape plot, but pasture and shifting cultivation possessed a significantly higher number of individuals, seedlings and adults than the seasonal semideciduous forest, plus they possessed a greater seedling/adult ratio. Shifting cultivation was found to be favorable for fructification. The present study found that shifting cultivation and pastures are landscape practices that can contribute to the rapid expansion and establishment of A. speciosa, which can become a dominant species in the region of Araripe.

Assessing the use of forest islands by parrot species in a neotropical savanna

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Igor Berkunsky

2015-06-01

Full Text Available Understanding the effect of habitat fragmentation is a fundamental yet complicated aim of many ecological studies. Beni savanna is a naturally fragmented forest habitat, where forest islands exhibit variation in resources and threats. To understand how the availability of resources and threats affect the use of forest islands by parrots, we applied occupancy modeling to quantify use and detection probabilities for 12 parrot species on 60 forest islands. The presence of urucuri (Attalea phalerata and macaw (Acrocomia aculeata palms, the number of tree cavities on the islands, and the presence of selective logging,and fire were included as covariates associated with availability of resources and threats. The model-selection analysis indicated that both resources and threats variables explained the use of forest islands by parrots. For most species, the best models confirmed predictions. The number of cavities was positively associated with use of forest islands by 11 species. The area of the island and the presence of macaw palm showed a positive association with the probability of use by seven and five species, respectively, while selective logging and fire showed a negative association with five and six species, respectively. The Blue-throated Macaw (Ara glaucogularis, the critically endangered parrot species endemic to our study area, was the only species that showed a negative association with both threats. Monitoring continues to be essential to evaluate conservation and management actions of parrot populations. Understanding of how species are using this natural fragmented habitat will help determine which fragments should be preserved and which conservation actions are needed.

Risk factors associated with Trypanosoma cruzi exposure in domestic dogs from a rural community in Panama.

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Saldaña, Azael; Calzada, José E; Pineda, Vanessa; Perea, Milixa; Rigg, Chystrie; González, Kadir; Santamaria, Ana Maria; Gottdenker, Nicole L; Chaves, Luis F

2015-11-01

Chagas disease, caused by Trypanosoma cruzi infection, is a zoonosis of humans, wild and domestic mammals, including dogs. In Panama, the main T. cruzi vector is Rhodnius pallescens, a triatomine bug whose main natural habitat is the royal palm, Attalea butyracea. In this paper, we present results from three T. cruzi serological tests (immunochromatographic dipstick, indirect immunofluorescence and ELISA) performed in 51 dogs from 24 houses in Trinidad de Las Minas, western Panama. We found that nine dogs were seropositive (17.6% prevalence). Dogs were 1.6 times more likely to become T. cruzi seropositive with each year of age and 11.6 times if royal palms where present in the peridomiciliary area of the dog's household or its two nearest neighbours. Mouse-baited-adhesive traps were employed to evaluate 12 peridomestic royal palms. All palms were found infested with R. pallescens with an average of 25.50 triatomines captured per palm. Of 35 adult bugs analysed, 88.6% showed protozoa flagellates in their intestinal contents. In addition, dogs were five times more likely to be infected by the presence of an additional domestic animal species in the dog's peridomiciliary environment. Our results suggest that interventions focused on royal palms might reduce the exposure to T. cruzi infection.

Ectoparasites and endoparasites of peridomestic house-rats in ile-ife, Nigeria and implication on human health.

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Titus Ogunniyi

2014-03-01

Full Text Available There has never been a single case report of any parasitic zoonosis in Ile-Ife while just a case of human Acanthocephalan infection in Nigeria is available.Fifty (house-rats Rattus rattus (Linnaeus, 1758 were caught in houses and raw food sellers' stalls in a market in Ile-Ife. A caught rat was removed from the cage and sacrificed by cervical jerking. A rat was weighed, measured, quickly following which thick and thin blood films on microscope slides were made from blood collected from the tail vein. The rat was examined for ectoparasites then dissected to check for endoparasites.Two ectoparasites (Xenopsylla cheopis and Laelaptid mite were recovered from 19 (38.0% of the rats. Five genera of helminthes (Moniliformis, Hymenolepis, Taenia, Trichuris and Trichinella were recovered from 29 (58.0% of the rats while seven genera of protozoa organisms (Amoeba, Dientamoeba, Entamoeba, Retortamonas, Trichomonas, Chilomastix and Trypanosoma were recovered from 48 (96.0% of them. There was no correlation (Spearman's correlation coefficient = -0.111 between the weight of the individual rat and the total number of alimentary canal acquired parasites.In relation to human health, implications of the rats serving as reservoir hosts for the different pathogens are highlighted. In view of the possibility of unexpected zoonosis arising from the parasites found in the peridomestic rats in this investigation and others not found, and in view of the difficulties that may be associated with diagnosing such ailment, especially by a clinician who trained locally, this report should be like raising awareness to these salient facts.

Ecology of Glossina species inhabiting peridomestic agroecosystems in relation to options for tsetse fly control

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Madubunyi, L.C.

1990-01-01

Unbaited blue biconical traps were used to sample populations of Glossina once a week from April 1984 to March 1988 in three peridomestic agroecosystems of the Nsukka area, Nigeria. Serological analysis of 1764 fly midgut contents revealed that G. tachinoides had fed on reptiles, birds and mammals, with the domestic pig accounting for 88.08% of the 730 identifiable bloodmeals. The frequency distribution of flies in various stages of the trophic cycle showed that males and females feed at 2.88 ± 0.42 and 2.43 ± 0.44 day intervals, respectively. Flies were caught in greater numbers in biotopes containing domestic pigs, while the presence of man depressed trap catches. The larger the pig population in an agroecosystem, the larger the G. tachinoides population. However, reduction in the pig population to below five triggered the collapse of one of the G. tachinoides populations, which disappeared following the removal of all the pigs. The fly populations exhibited marked seasonal fluctuations in apparent density, largely caused by routine agronomic practices. These density fluctuations undermine recruitment of new adults into the population, especially during the wet season. It is suggested that tsetse populations in this area, already being kept at low density by routine agricultural procedures, could be further reduced by combining insecticides impregnated traps or targets with insect proofing of the piggeries. Methods aimed at undermining the recruitment of young adults into tsetse populations, capitalizing on naturally occurring sex ratio distortion as well as on maintaining populations of preferred hosts of the tsetse fly at low levels, should form part of integrated tsetse control packages. Selection of sterile male release sites and the number of sterile males to be released in them during sterile insect technique campaigns should take into account the sex ratio dynamics of target tsetse populations. 28 ref, 9 figs, 8 tabs

New structures for goat corrals to control peridomestic populations of Triatoma infestans (Hemiptera: Reduviidae in the Gran Chaco of Argentina

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David Eladio Gorla

2013-05-01

Full Text Available Goat production is an important economic activity for rural communities in the Gran Chaco of Argentina. Goat corrals are important for the survival of peridomestic populations of Triatoma infestans. This study evaluated the impact of modifying the traditional structure of goat corrals on T. infestans populations and goat productivity in the region of Los Llanos (La Rioja. Thirty-nine experimental corrals were constructed and 57 traditional corrals were used as controls. We evaluated the infestations of the control and experimental corrals for five years following construction of the structures. The results showed that the new structures did not prevent the colonization, although it enhanced the detection of infestation at low densities of T. infestans. No significant difference was found in T. infestans population abundance between control and experimental corrals, probably because of the different detectability in the two types of structures, especially among the small nymphs. Although goat productivity average was higher in experimental than in control corrals, no significant difference was found because of high variability. The new structures can be used as a complement to promote the development of rural communities. Acceptability and adoption of the new corrals by the owners was high, as the enclosures offered better protection for the goats, increased growth of kids and facilitated herd handling.

One more piece in the VACV ecological puzzle: could peridomestic rodents be the link between wildlife and bovine vaccinia outbreaks in Brazil?

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Abrahão, Jônatas S; Guedes, Maria Isabel M; Trindade, Giliane S; Fonseca, Flávio G; Campos, Rafael K; Mota, Bruno F; Lobato, Zélia I P; Silva-Fernandes, André T; Rodrigues, Gisele O L; Lima, Larissa S; Ferreira, Paulo C P; Bonjardim, Cláudio A; Kroon, Erna G

2009-10-19

Despite the fact that smallpox eradication was declared by the World Health Organization (WHO) in 1980, other poxviruses have emerged and re-emerged, with significant public health and economic impacts. Vaccinia virus (VACV), a poxvirus used during the WHO smallpox vaccination campaign, has been involved in zoonotic infections in Brazilian rural areas (Bovine Vaccinia outbreaks - BV), affecting dairy cattle and milkers. Little is known about VACV's natural hosts and its epidemiological and ecological characteristics. Although VACV was isolated and/or serologically detected in Brazilian wild animals, the link between wildlife and farms has not yet been elucidated. In this study, we describe for the first time, to our knowledge, the isolation of a VACV (Mariana virus - MARV) from a mouse during a BV outbreak. Genetic data, in association with biological assays, showed that this isolate was the same etiological agent causing exanthematic lesions observed in the cattle and human inhabitants of a particular BV-affected area. Phylogenetic analysis grouped MARV with other VACV isolated during BV outbreaks. These data provide new biological and epidemiological information on VACV and lead to an interesting question: could peridomestic rodents be the link between wildlife and BV outbreaks?

Coxiella burnetii and Rickettsia conorii: Two zoonotic pathogens in peridomestic rodents and their ectoparasites in Nigeria.

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Kamani, Joshua; Baneth, Gad; Gutiérrez, Ricardo; Nachum-Biala, Yaarit; Mumcuoglu, Kosta Y; Harrus, Shimon

2018-01-01

Rodents are hosts of numerous pathogenic agents of public health importance globally. Their ability to harbor these pathogens without showing overt clinical signs of disease has epidemiologic consequences. In some rural settings in Nigeria, humans and rodents do not only share feeds and abode, but the latter may end up on the table of the former as a source of protein, thereby increasing the risks of disease transmission. Molecular assays were used to detect and characterize two agents of zoonotic importance, Coxiella burnetii and Rickettsia spp. in 194 peridomestic rodents captured in a peri-urban setting in Nigeria, and 32 pools of ectoparasites removed from them, to determine their possible role in the epidemiology of these diseases in this country. Targeting and characterizing the insertion sequence IS1111, C. burnetii DNA was detected in 4 out of 194 (2.1%) rodents comprising 3 out of 121 (2.5%) Rattus norvegicus and 1 out of 48 (2.1%) Rattus rattus screened in this study. Rickettsia spp. DNA was detected in two Rhipicephalus sanginueus sensu lato pools (i.e. RT1 and RT4) using the citrate synthase (gltA) gene and further characterized by amplification and sequence analysis of six genes to determine their identity. The RT1 sample consistently gave 98-100% identity to Rickettsia conorii str. Malish 7 for the various genes and loci studied. However, the identity of RT4 could not be definitively determined due to variable identities to different Rickettsia spp. according to the gene or loci under consideration. Further isolation study to determine if the RT4 characterized is a new variant or a mixture of sequences of different rickettsiae within the pool will be worthwhile. Copyright © 2017 Elsevier GmbH. All rights reserved.

Comparación de métodos para la captura de triatominos (Hemiptera: Reduviidae en palmas Attalea butyracea en los Llanos Orientales de Colombia

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Víctor Manuel Angulo

2013-12-01

Full Text Available Introducción. El estudio de los triatominos en sus ecótopos naturales tiene gran significado en la epidemiología de la enfermedad de Chagas. La recolección de insectos vivos y su establecimiento en insectarios permite realizar incontables estudios. Por ello se necesitan métodos efectivos para la captura de triatominos silvestres, especialmente especies intrusas como Rhodnius prolixus. Objetivo. Comparar cuatro métodos para la captura de triatominos en palmas para medir su efectividad. Materiales y métodos. El estudio se llevó a cabo en la localidad de Maní, departamento de Casanare, Colombia, con predominio de Attalea butyracea. Se compararon cuatro metodologías en 67 palmas: trampas con cebo vivo, búsqueda directa en palmas, tala y disección. Resultados. Los métodos fueron efectivos para recolectar ejemplares juveniles y adultos. La tala y la búsqueda manual mostraron los mayores índices de infestación (100 % y 83,33 %. La trampa Angulo mostró mayores índices de hacinamiento (4,93, densidad (3,76, rango de abundancia (1-13 e índice adulto/ninfa (0,22. La tala y la disección fue el método que significativamente recolectó más triatominos en comparación con los otros (p0,05. Conclusiones. Aunque la tala fue el mejor método para la recolección del mayor número de triatominos, los métodos con el cebo vivo con adhesivos o refugios para atrapar los insectos, fueron una buena alternativa. Entre ellos, la trampa Angulo mostró mejores resultados y evitó la exposición del investigador al riesgo y la intervención de ecotopos naturales.   doi: http://dx.doi.org/10.7705/biomedica.v33i4.835

Domestic, peridomestic and wild hosts in the transmission of Trypanosoma cruzi in the Caatinga area colonised by Triatoma brasiliensis

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Claudia Mendonça Bezerra

2014-11-01

Full Text Available The role played by different mammal species in the maintenance of Trypanosoma cruzi is not constant and varies in time and place. This study aimed to characterise the importance of domestic, wild and peridomestic hosts in the transmission of T. cruzi in Tauá, state of Ceará, Caatinga area, Brazil, with an emphasis on those environments colonised by Triatoma brasiliensis. Direct parasitological examinations were performed on insects and mammals, serologic tests were performed on household and outdoor mammals and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53, while in pigs it was 6% (2/34. The percentages of the most abundantly infected wild animals were as follows: Thrichomys laurentius 74% (83/112 and Kerodon rupestris 10% (11/112. Of the 749 triatomines collected in the household research, 49.3% (369/749 were positive for T. brasiliensis, while 6.8% were infected with T. cruzi (25/369. In captured animals, T. brasiliensis shares a natural environment with T. laurentius, K. rupestris, Didelphis albiventris, Monodelphis domestica, Galea spixii, Wiedomys pyrrhorhinos, Conepatus semistriatus and Mus musculus. In animals identified via their food source, T. brasiliensis shares a natural environment with G. spixii, K. rupestris, Capra hircus, Gallus gallus, Tropidurus oreadicus and Tupinambis merianae. The high prevalence of T. cruzi in household and peridomiciliar animals reinforces the narrow relationship between the enzootic cycle and humans in environments with T. brasiliensis and characterises it as ubiquitous.

Infestation of Palm Trees by Triatomines (Hemiptera: Reduviidae in the State of Bahia, Brazil

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Rodrigo Gurgel-Gonçalves

2012-12-01

Resumo. As palmeiras desempenham papéis importantes como habitats de reprodução e alimentação para triatomíneos silvestres, vetores da doença de Chagas. A ocorrência de triatomíneos em palmeiras peridomiciliares pode aumentar o risco de invasão desses insetos em domicílios e deve ser considerada para desenvolver estratégias de prevenção. Com objetivo de investigar a infestação de palmeiras por triatomíneos no Estado da Bahia e determinar a infecção natural desses insetos por Trypanosoma spp., foram amostradas 183 palmeiras em 12 municípios entre 2006 e 2011 utilizando captura manual e/ou armadilhas adesivas iscadas com camundongos. Os triatomíneos foram detectados em 79 palmeiras (43% das espécies Copernicia prunifera (Mart. Becc., Mauritia flexuosa L. e Attalea spp. (Attalea burretiana Bondar ou Attalea salvadorensis Glassman. Em outras espécies de palmeiras (Syagrus coronata (Mill H.E. Moore, Attalea funifera Mart ex. Spreng e Elaeis guineensis Jacq não foram detectados triatomíneos. Rhodnius neglectus Lent, Triatoma sordida (Stål, e Triatoma pseudomaculata Corrêa & Espínola ocorreram em C. prunifera ao longo do rio São Francisco. No extremo oeste da Bahia, R. neglectus e Psammolestes tertius Lent & Jurberg foram detectados em M. flexuosa, enquanto Triatoma tibiamaculata (Pinto ocorreu em Attalea sp. em áreas urbanas de Salvador. No total, 180 triatomíneos foram capturados, principalmente R. neglectus. A maior taxa de infecção natural (61% foi observada em T. tibiamaculata. Os resultados indicam que pelo menos três espécies de palmeiras são habitats favoráveis para triatomíneos no estado da Bahia e ocorrem no ambiente peridomiciliar, o que pode aumentar a probabilidade de invasão de triatomíneos nas casas.

Phenotypic variability of Rhodnius ecuadoriensis populations at the Ecuadorian central and southern Andean region.

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Villacís, Anita G; Grijalva, Mario J; Catalá, Silvia S

2010-11-01

Rhodnius ecuadoriensis is an important vector of Chagas disease in Ecuador. Whereas only sylvatic and peridomestic populations are common in Manabi province, this species occupies domestic, peridomestic, and sylvatic habitats in Loja province where high reinfestation of houses was observed. To explore the existence of phenetic changes linked to the domiciliation of the species, this study set out to analyze the wing and antennal phenotypes of R. ecuadoriensis in these two provinces where the vector presents different affinity for domestic habitats. The antennal phenotype and the wing size and shape distinguish the two geographical populations of R. ecuadoriensis. In Manabí, sylvatic and peridomestic specimens were very similar. In Loja, sylvatic and nonsylvatic (domestic and peridomestic) populations showed distinctive characteristics. Remarkable sexual dimorphism of wing and antenna, exclusive of domestic specimens, and high metric disparity in the wing shape of the domestic females point out the existence of a particular situation in this habitat. The results of this phenotypic analysis and previous evidence of behavioral differences support the hypothesis of disruptive selection acting upon R. ecuadoriensis populations.

COMPOSICIÓN FLORÍSTICA Y ESTRUCTURA DE LOS BOSQUES RIBEREÑOS DE LA CUENCA BAJA DEL RÍO PAUTO, CASANARE, COLOMBIA

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Diego Mauricio Cabrera-Amaya

2016-01-01

Full Text Available Se caracterizó la composición florística y aspectos de la estructura de la vegetación en bosques ribereños de la cuenca baja del río Pauto (Colombia, Casanare utilizando la información de nueve parcelas de 20 x 50 m (1000 m², se midieron el diámetro a la altura del pecho (DAP, la altura total y cobertura de la copa. Se analizó la riqueza y los valores de importancia por especie y por familia. Se realizó un análisis para establecer una clasificación local de los tipos de bosque, los cuales se describieron en términos de clases diamétricas y altimétricas, diagramas estructurales e índice de predominio fisionómico. Se registraron 185 especies, 127 géneros y 56 familias, la mayor riqueza florística se agrupó en las familias Rubiaceae, Moraceae, Myrtaceae, Fabaceae y Bignoniaceae y en los géneros Ficus, Piper, Psychotria e Inga. Las familias con mayor IVF fueron Arecaceae, Fabaceae, Euphorbiaceae, Moraceae y Verbenaceae. Las especies más importantes según su IVI fueron: Attalea butyracea, Clarisia biflora, Sarcaulus brasiliensis, Dendropanax arboreus e Inga interrupta. Se encontraron seis comunidades, de las cuales sólo la primera se ha mencionado con anterioridad: 1 Palmar de Mauritia flexuosa y Euterpe precatoria, 2 Bosque de galería de Copaifera pubiflora y Homalium racemosum, 3 Bosque de vega de Discocarpus spruceanus y Sloanea terniflora, 4 Bosque de vega de Attalea butyracea y Garcinia madruno, 5 Bosque de galería de Attalea butyracea e Inga interrupta, y 6 Bosque de vega Attalea butyracea y Clarisia biflora. Los bosques presentan múltiples estratos con alturas del dosel desde los 18 m sobre las riberas de los caños, hasta 25 m en las vegas de los ríos. La riqueza y la composición concuerdan con los patrones florísticos de la Orinoquía colombiana, especialmente a nivel de familia, pero son menos las coincidencias a nivel de género y especie. La concentración de individuos en clases diamétricas pequeñas es

Controle do Triatoma sordida no peridomicílio rural do município de Porteirinha, Minas Gerais, Brasil Control of Triatoma sordida in the rural peridomestic environment of Porteirinha municipality, Minas Gerais, Brazil

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Liléia Diotaiuti

1998-01-01

baixa permanência do inseticida no peridomicílio, a existência de apenas um ciclo anual do triatomíneo e a lentidão na reconstituição da população original sugerem que uma borrifação anual é suficiente para controle do T. sordida. Maior eficiência poderá ser obtida com a eliminação dos esconderijos, através da substituição do material usado na construção dos anexos, principalmente a madeira.Triatoma sordida, a predominantly peridomestic species, is currently the triatomine species most frequently collected in Brazil. To evaluate the effectiveness of control activities against this species, a survey to determine infestation rates was carried out in October 1993 in 12 rural localities in the municipality of Porteirinha, State of Minas Gerais, Brazil. In the survey, 772 T. sordida were captured, of which 3.6% were infected with Trypanosoma cruzi. Of the 406 dwellings investigated, 34.9% were infested, and 27.6% of 695 peridomiciliar ecotopes contained T. sordida. The area around the dwellings was relatively uniform, with few positive ecotopes per household and low triatomine densities (a maximum of five insects per colony. The study found an association between the presence of insects and wood: 72.8% of the insects were captured in this type of ecotope. The majority of the positive households (62.9% were close to forests (12 to 299 m; 92.3% of the infested ecotopes were less than 20 m from the house. A census of peridomestic animals revealed that chickens were the most abundant (82.7%. All positive households found in the survey were sprayed immediately with deltamethrin (25 mg a.i./m². New surveys were carried out 7 months (survey 2 and 12 months (survey 3 after spraying. In survey 2, the number of insects collected corresponded to 52.5% of the original total, and in survey 3, 79.1%. The decrease in population observed in survey 2 was mainly due to a reduction in the population of nymphs. The large proportion of adults captured in that survey

Aplicación del bioensayo de Artemia salina en el análisis general de plantas medicinales brasileñas

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Montanher, Ana Beatriz Pimentel; Pizzolatti, Moacir Geraldo; Brighente, Inês Maria Costa

2002-01-01

Extractos de once especies de la flora brasileña fueron estudiados para evaluar la actividad citotóxica por el test de Artemia salina. Las plantas seleccionadas fueron: Baccharis pseudotenuifolia, Baccharis ligustrina, Baccharis platypoda, Baccharis coridifolia, Polygala paniculata, Polygala sabulosa, Croton celtidifolius, Cyathea phalerata, Trichilia catigua, Eugenia uniflora y Schinus molle. Los resultados obtenidos para los extractos crudos de B. pseudotenuifolia, B. ligustrina, B. c...

Useful palms (Arecaceae near Iquitos, Peruvian Amazon

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Henrik Balslev

2014-03-01

Full Text Available This paper describes the uses of 64 species of palms in 28 villages in Departamento de Loreto, Peru. There, the palms are of great use as food (Bactris gasipaes, Mauritia flexuosa, Euterpe precatoria, Oenocarpus bataua, for fiber production (Astrocaryum chambira, Aphandra natalia, for construction of houses (Euterpe precatoria, Iriartea deltoidea,Socratea exorrhiza, thatching (many species of Attalea, Lepidocaryum tenue and for many medicinal purposes (Euterpe precatoria, Oenocarpus bataua.

SUPLEMENTAÇÃO COM AMÊNDOA DE BACURI NA COMPOSIÇÃO CORPORAL DE RATOS SUBMETIDOS AO EXERCÍCIO

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Marília de Lima Mendes Ramos

Full Text Available RESUMO Introdução: A proteína da amêndoa do bacuri (Attalea phalerata Mart. Ex Spreng e da whey protein (WP têm quantidades relevantes de aminoácidos essenciais e são de boa digestibilidade, características que têm sido buscadas por atletas para auxílio para melhorar a composição corporal, particularmente quando associadas a exercícios. Objetivo: Avaliar o efeito de dietas com teor proteico vegetal e animal sobre a composição corporal de ratos Wistar submetidos ao exercício resistido em escada. Métodos: Quarenta ratos machos recém-desmamados foram submetidos a um período de adaptação com dieta comercial (4 semanas e treinamento resistido durante oito semanas (três vezes por semana, recebendo dietas com farinha de bacuri e whey protein. Foram distribuídos randomicamente em seis grupos: G1 (bacuri sedentário, G2 (bacuri exercitado, G3 (WP sedentário, G4 (WP exercitado, G5 (controle sedentário e G6 (controle exercitado. Avaliou-se consumo da dieta, peso corporal, comprimento, circunferências torácica e abdominal para calcular o índice de Lee e o índice de massa corporal; os sítios com gordura foram retirados após eutanásia. A análise estatística foi realizada por ANOVA e Teste de Tukey, considerando 5% de significância. Resultados: O peso final do G3 (372 ± 8,86 g foi superior ao do G2 (326,83 ± 15,03 g e do G6 (316,75 ± 5,90 g; os grupos que receberam dieta com farinha de bacuri consumiram quantidade superior de dieta, porém, tiveram menor peso final; não diferiram no índice de Lee e no IMC, sítios com gordura e índice de adiposidade com relação aos grupos tratados com WP, apresentando valores inferiores das circunferências torácica e abdominal. Com relação às gorduras e índice de adiposidade, não houve diferença entre os grupos sedentários e exercitados. Conclusão: A proteína da amêndoa de bacuri mostrou-se de boa qualidade quando comparada com a whey protein, havendo possibilidade de

Alkaline treatment on piassava (Attalea funifera martius) fiber

International Nuclear Information System (INIS)

Santos, E.B.C.; Moreno, C.G.; Barros, J.J.P.; Moura, D.A.; Fim, F.C.; Wellen, R.M.R.; Silva, L.B.

2016-01-01

Alkaline treatment on piassava fiber with size inferior to 270 mesh was performed to remove impurities. The treatments took place under magnetic stirring and Sodium Hydroxide (NaOH) solution with 2, 4, 6 and 8% of concentration; processing time ranged between 100 and 400 minutes, with intervals of 25 minutes; the main object was to reach the optimum concentration and time. The concentration 2% was used to remove efficiently the impurities without damaging excessively the fiber. The fibers were characterized by means of X-ray diffraction (XRD) and optical microscopy (OM). Fibers presented XRD diffraction peak around 22 deg, due to the crystalline structure of cellulose. By optical microscopy was observed the treatment efficacy of the 2% NaOH solution in removing surface impurities. (author)

The opossum Didelphis virginiana as a synanthropic reservoir of Trypanosoma cruzi in Dzidzilché, Yucatán, México.

Science.gov (United States)

Ruiz-Pina, Hugo A; Cruz-Reyes, Alejandro

2002-07-01

In México, the role of mammals in the transmission cycle of Trypanosoma cruzi is poorly known. In the State of Yucatán, an endemic area of Chagas disease, both Didelphis virginiana and D. marsupialis occur sympatrically. However, until now, only the former species had been found infected with T. cruzi. To evaluate the role of D. virginiana in a peridomestic transmission, nine periods of capture-recapture were performed around the village of Dzidzilché, Yucatán. The sex, age, reproductive status, location, and presence of infection with T. cruzi were recorded for each opossum. The chromosome morphology was used to identify the opossum species. T. cruzi was identified by the presence of pseudocysts of amastigotes in cardiac muscle fibers of Balb/c mice inoculated with strains isolated from opossums. However, xenodiagnosis was the best diagnostic method. Triatoma dimidiata, the vector, were collected in and around the opossums' nests, and human dwellings; and were checked for T. cruzi. From 102 blood samples of D. virginiana examined 55 (53.9%) were positive to T. cruzi, the only two D. marsupialis captured were negative. Significant differences were found between infection, and both sex and reproductive condition. Eight out of 14 triatomines collected in peridomestic nests (57.1%), and 32 of 197 captured inside houses (16.3%) were found infected, suggesting a peridomestic transmission. The statistically high abundance of infected opossums and triatomines during the dry season (March to May) suggested the existence of a seasonality in the peridomestic transmission of T. cruzi in Dzidzilché.

Ecoepidemiology, short history and control of Chagas disease in the endemic countries and the new challenge for non-endemic countries

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José Rodrigues Coura

2014-11-01

Full Text Available Chagas disease is maintained in nature through the interchange of three cycles: the wild, peridomestic and domestic cycles. The wild cycle, which is enzootic, has existed for millions of years maintained between triatomines and wild mammals. Human infection was only detected in mummies from 4,000-9,000 years ago, before the discovery of the disease by Carlos Chagas in 1909. With the beginning of deforestation in the Americas, two-three centuries ago for the expansion of agriculture and livestock rearing, wild mammals, which had been the food source for triatomines, were removed and new food sources started to appear in peridomestic areas: chicken coops, corrals and pigsties. Some accidental human cases could also have occurred prior to the triatomines in peridomestic areas. Thus, triatomines progressively penetrated households and formed the domestic cycle of Chagas disease. A new epidemiological, economic and social problem has been created through the globalisation of Chagas disease, due to legal and illegal migration of individuals infected by Trypanosoma cruzi or presenting Chagas disease in its varied clinical forms, from endemic countries in Latin America to non-endemic countries in North America, Europe, Asia and Oceania, particularly to the United States of America and Spain. The main objective of the present paper was to present a general view of the interchanges between the wild, peridomestic and domestic cycles of the disease, the development of T. cruzi among triatomine, their domiciliation and control initiatives, the characteristics of the disease in countries in the Americas and the problem of migration to non-endemic countries.

The opossum Didelphis virginiana as a synanthropic reservoir of Trypanosoma cruzi in Dzidzilché, Yucatán, México

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Hugo A Ruiz-Piña

2002-07-01

Full Text Available In México, the role of mammals in the transmission cycle of Trypanosoma cruzi is poorly known. In the State of Yucatán, an endemic area of Chagas disease, both Didelphis virginiana and D. marsupialis occur sympatrically. However, until now, only the former species had been found infected with T. cruzi. To evaluate the role of D. virginiana in a peridomestic transmission, nine periods of capture-recapture were performed around the village of Dzidzilché, Yucatán. The sex, age, reproductive status, location, and presence of infection with T. cruzi were recorded for each opossum. The chromosome morphology was used to identify the opossum species. T. cruzi was identified by the presence of pseudocysts of amastigotes in cardiac muscle fibers of Balb/c mice inoculated with strains isolated from opossums. However, xenodiagnosis was the best diagnostic method. Triatoma dimidiata, the vector, were collected in and around the opossums' nests, and human dwellings; and were checked for T. cruzi. From 102 blood samples of D. virginiana examined 55 (53.9% were positive to T. cruzi, the only two D. marsupialis captured were negative. Significant differences were found between infection, and both sex and reproductive condition. Eight out of 14 triatomines collected in peridomestic nests (57.1%, and 32 of 197 captured inside houses (16.3% were found infected, suggesting a peridomestic transmission. The statistically high abundance of infected opossums and triatomines during the dry season (March to May suggested the existence of a seasonality in the peridomestic transmission of T. cruzi in Dzidzilché.

Sex, subdivision, and domestic dispersal of Trypanosoma cruzi lineage I in southern Ecuador.

Science.gov (United States)

Ocaña-Mayorga, Sofía; Llewellyn, Martin S; Costales, Jaime A; Miles, Michael A; Grijalva, Mario J

2010-12-14

Molecular epidemiology at the community level has an important guiding role in zoonotic disease control programmes where genetic markers are suitably variable to unravel the dynamics of local transmission. We evaluated the molecular diversity of Trypanosoma cruzi, the etiological agent of Chagas disease, in southern Ecuador (Loja Province). This kinetoplastid parasite has traditionally been a paradigm for clonal population structure in pathogenic organisms. However, the presence of naturally occurring hybrids, mitochondrial introgression, and evidence of genetic exchange in the laboratory question this dogma. Eighty-one parasite isolates from domiciliary, peridomiciliary, and sylvatic triatomines and mammals were genotyped across 10 variable microsatellite loci. Two discrete parasite populations were defined: one predominantly composed of isolates from domestic and peridomestic foci, and another predominantly composed of isolates from sylvatic foci. Spatial genetic variation was absent from the former, suggesting rapid parasite dispersal across our study area. Furthermore, linkage equilibrium between loci, Hardy-Weinberg allele frequencies at individual loci, and a lack of repeated genotypes are indicative of frequent genetic exchange among individuals in the domestic/peridomestic population. These data represent novel population-level evidence of an extant capacity for sex among natural cycles of T. cruzi transmission. As such they have dramatic implications for our understanding of the fundamental genetics of this parasite. Our data also elucidate local disease transmission, whereby passive anthropogenic domestic mammal and triatomine dispersal across our study area is likely to account for the rapid domestic/peridomestic spread of the parasite. Finally we discuss how this, and the observed subdivision between sympatric sylvatic and domestic/peridomestic foci, can inform efforts at Chagas disease control in Ecuador.

Sex, subdivision, and domestic dispersal of Trypanosoma cruzi lineage I in southern Ecuador.

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Sofía Ocaña-Mayorga

2010-12-01

Full Text Available Molecular epidemiology at the community level has an important guiding role in zoonotic disease control programmes where genetic markers are suitably variable to unravel the dynamics of local transmission. We evaluated the molecular diversity of Trypanosoma cruzi, the etiological agent of Chagas disease, in southern Ecuador (Loja Province. This kinetoplastid parasite has traditionally been a paradigm for clonal population structure in pathogenic organisms. However, the presence of naturally occurring hybrids, mitochondrial introgression, and evidence of genetic exchange in the laboratory question this dogma.Eighty-one parasite isolates from domiciliary, peridomiciliary, and sylvatic triatomines and mammals were genotyped across 10 variable microsatellite loci. Two discrete parasite populations were defined: one predominantly composed of isolates from domestic and peridomestic foci, and another predominantly composed of isolates from sylvatic foci. Spatial genetic variation was absent from the former, suggesting rapid parasite dispersal across our study area. Furthermore, linkage equilibrium between loci, Hardy-Weinberg allele frequencies at individual loci, and a lack of repeated genotypes are indicative of frequent genetic exchange among individuals in the domestic/peridomestic population.These data represent novel population-level evidence of an extant capacity for sex among natural cycles of T. cruzi transmission. As such they have dramatic implications for our understanding of the fundamental genetics of this parasite. Our data also elucidate local disease transmission, whereby passive anthropogenic domestic mammal and triatomine dispersal across our study area is likely to account for the rapid domestic/peridomestic spread of the parasite. Finally we discuss how this, and the observed subdivision between sympatric sylvatic and domestic/peridomestic foci, can inform efforts at Chagas disease control in Ecuador.

Ecotope effect in Triatoma brasiliensis (Hemiptera: Reduviidae) suggests phenotypic plasticity rather than adaptation.

Science.gov (United States)

Batista, V S P; Fernandes, F A; Cordeiro-Estrela, P; Sarquis, O; Lima, M M

2013-09-01

Triatoma brasiliensis (Hemiptera: Reduviidae) is an important vector of Chagas' disease in both sylvatic and peridomestic ecotopes. Discriminating between these populations of Triatominae has been proposed as a means of investigating re-infestation rates of human dwellings. Geometric morphometrics have been widely applied in the study of Triatominae polymorphisms at species and population levels. This study characterizes morphometric differences between sylvatic and peridomestic populations, as well as between sexes in T. brasiliensis specimens from Jaguaruana, Ceará, in northeastern Brazil. No differences in either the shape or size of the cephalic capsule were apparent between sexes or ecotopes. However, the wings showed differentiation in shape and size. Sexual dimorphism was detected, with females presenting significantly higher values and conformations. Size differentiation was also evident, with sylvatic specimens being generally larger than peridomestic examples. These results indicate that differences in the wings of T. brasiliensis may be related to the existence of phenotypic plasticity, and variations in size and shape may be associated with different ecotopes, possibly as a result of conditions in each micro-habitat, such as temperature, relative humidity, food supply and density. © 2012 The Royal Entomological Society.

Wing geometry as a tool for studying the Lutzomyia longipalpis (Diptera: Psychodidae complex

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J De la Riva

2001-11-01

Full Text Available Toro Toro (T and Yungas (Y have been described as genetically well differentiated populations of the Lutzomyia longipalpis (Lutz & Neiva, 1912 complex in Bolivia. Here we use geometric morphometrics to compare samples from these populations and new populations (Bolivia and Nicaragua, representing distant geographical origins, qualitative morphological variation ("one-spot" or "two-spots" phenotypes, ecologically distinct traits (peridomestic and silvatic populations, and possibly different epidemiological roles (transmitting or nor transmitting Leishmania chagasi. The Nicaragua (N (Somotillo sample was "one-spot" phenotype and a possible peridomestic vector. The Bolivian sample of the Y was also "one-spot" phenotype and a demonstrated peridomestic vector of visceral leishmaniasis (VL. The three remaining samples were silvatic, "two-spots" phenotypes. Two of them (Uyuni and T were collected in the highlands of Bolivian where VL never has been reported. The last one (Robore, R came from the lowlands of Bolivia, where human cases of VL are sporadically reported. The decomposition of metric variation into size and shape by geometric morphometric techniques suggests the existence of two groups (N/Y/R, and U/T. Several arguments indicate that such subdivision of Lu. longipalpis could correspond to different evolutionary units.

A revision of thirteen species of Triatominae (Hemiptera: Reduviidae vectors of Chagas disease in Mexico

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Salazar-Schettino Paz Maria

2010-10-01

Full Text Available Vectors of Trypanosoma cruzi, parasite responsible for Chagas disease, are divided in intradomestic, peridomestic and sylvatic. The intradomestic are Triatoma barberi and Triatoma dimidiata, two species that represent the highest health risk among the Mexican population. Triatoma dimidiata is a species found mainly inside human habitats, but in Yucatan, it corresponds to the peridomicile vectors. Also in the peridomicile most of Chagas disease vectors are found: Meccus bassolsae, M. longipennis, M. mazzottii, M pallidipennis, M. phyllosomus, M picturata, Triatoma gerstaeckeri, T mexicana, T rubida, Dipetalogaster máxima (the last two are in the process of becoming adapted to the domicile, Panstrongylus rufotuberculatus which occasionally enters the domicile in its adult stage, and Rhodnius prolixus, which is practically controlled in the country. Peridomestic vectors are of lower risk in the transmission dynamics, as compared to the intradomestic ones. For the control of the intradomestic vectors, health education programs, improvements of housing, and the use of pesticides are essential To control the peridomestic vectors, health education programs are required, as well as the use of mosquito nets on doors and windows and around beds, aside from cementing the stone wall fences.

Immatures of Acanthocinini (Coleoptera, Cerambycidae, Lamiinae

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Sônia A. Casari

2014-06-01

Full Text Available Immatures of Acanthocinini (Coleoptera, Cerambycidae, Lamiinae. Larva and pupa of Eutrypanus dorsalis (Germar, 1928, collected in trunks of Pinus elliottii Engelm., and Paratenthras martinsi Monné, 1998, collected in spathes of Scheelea phalerata (Mart. ex Spreng. Burret, are described and illustrated. Larva and pupa of Lophopoeum timbouvae Lameere, 1884, collected in Hymenaea corbaril L., Enterolobium contortisiliquum (Vell. Morong and Pterogyne nitens Tul., are redescribed and illustrated. A table with all described immatures of Lamiinae, and a comparison among the immatures of Acanthocinini are presented. Biological notes and new records are also included.

Palm diversity and abundance in the Colombian Amazon

DEFF Research Database (Denmark)

Balslev, Henrik; Copete, Juan Carlos; Pedersen, Dennis

2017-01-01

We studied diversity and abundance of palms in the eastern Colombian Amazon in 71 transects, 61 measuring 5×500 m and 10 transects measuring 4×500 m, innventoring a total of 17.25 hectares. We found a total of 74 species in 21 genera. In terra firme we found 68 species in 20 genera and an average...... found in this study (Euterpe precatoria, Oenocarpus bataua, Attalea butyracea, Iriartella setigera) coincide with dominant species in other Amazonian palm communities....

Observations on the Domestic Ecology of Rhodnius ecuadoriensis (Triatominae

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Abad-Franch F

2002-01-01

Full Text Available Rhodnius ecuadoriensis infests peridomiciles and colonises houses in rural southern Ecuador. Six out of 84 dwellings (7% surveyed in a rural village were infested (78 bugs/infested domicile; 279 bugs were collected in a single dwelling. Precipitin tests revealed R. ecuadoriensis fed on birds (65%, rodents (31%, marsupials (8%, and humans (15% - mixed bloodmeals detected in 37.5% of individual samples. Trypanosoma cruzi from opossums and rodents may thus be introduced into the domestic cycle. Wasp parasitoidism was detected in 6.5% of 995 R. ecuadoriensis eggs (only in peridomestic habitats. Control strategies should integrate insecticide spraying (indoors and peridomestic, better management of poultry, and housing improvements. A possible inefficacy of Malathion is reported.

Active dispersal of Triatoma infestans and other triatomines in the Argentinean arid Chaco before and after vector control interventions.

Science.gov (United States)

Abrahan, Luciana; Gorla, David; Catalá, Silvia

2016-06-01

Peridomestic structures are considered the main sites where Triatoma infestans (Hemiptera: Reduviidae) remain and disperse, representing the first risk factor for intradomestic invasion, even after vector control activities. This study analyzed T. infestans dispersal during vector control interventions in six rural houses of the arid Chaco (La Rioja, Argentina). Flying and walking dispersers were captured during five months of two consecutive warm seasons after insecticide spraying of intra- and peridomiciles. These data were compared with previous published data in the same scenario but without insecticide spraying in peridomiciles. Recorded climatic conditions were favorable for active dispersion during the study. Total number of T. infestans dispersers moving among domestic habitats decreased after insecticide spraying. Sylvatic triatomines T. guasayana, T. eratyrusiformis, T. garciabesi, and T. platensis, not targeted by insecticide spraying, were captured simultaneously within peridomestic areas and showed higher invasion pressure than T. infestans. Adult T. infestans peridomestic populations showed high nutritional status, indicating low dispersion probability. Some peridomiciles remained infested at the end of the study. However, no intradomiciles were recolonized. These results suggest that there is a low probability of intradomestic recolonization by active dispersion from peridomiciles during 15 months post-spraying. © 2016 The Society for Vector Ecology.

In vitro germination and growth of babassu (orbygnia phalerata Mart ...

African Journals Online (AJOL)

CERRADONLINE

2012-06-07

Jun 7, 2012 ... samples were removed from the dry chambers to assess embryo viability using in vitro germination and the tetrazolium test, which was adapted from the method of Ribeiro et al. (2010). The experimental design was completely randomized, fully factorial (3 drying times × 2 drying temperatures) and used 4 ...

Seasonal field efficacy of pyriproxyfen autodissemination stations against container-inhabiting mosquito Aedes albopictus under different habitat conditions.

Science.gov (United States)

Suman, Devi Shankar; Wang, Yi; Faraji, Ary; Williams, Gregory M; Williges, Eric; Gaugler, Randy

2018-04-01

Control of the container-inhabiting mosquito, Aedes albopictus, is difficult using conventional methods due to its selection of cryptic peri-domestic habitats. We evaluated whether autodissemination stations can deliver sufficient pyriproxyfen to sentinel containers to produce significant pupal mortality in different habitats such as competing oviposition sites, peri-domestic habitats, junkyards and tire piles. We also tested how far the pesticide could be transferred over a 200-m range. Autodissemination stations performed effectively for 8-12 weeks under field conditions. Pupal mortality was reduced in sentinel cups with high-competing oviposition habitats (5 versus 20) in isolated plots; however, similar results were not seen in residential areas. Increasing the number of stations per plot (from 1 to 4) enhanced the efficacy. Peri-domestic habitat trials showed the highest pupal mortality (50.4%) and site contamination with pyriproxyfen (82.2%) among the trials. Autodissemination stations were able to contaminate habitats in a junkyard (50.0%) and tire piles (40.2%). Pyriproxyfen was detected in sentinel cups up to 200 m from stations. Detection of pyriproxyfen by residue analysis (0.005-0.741 µg L -1 ) in field samples confirmed the transfer of the insect growth regulator. Autodissemination stations have shown promising potential as a novel pest management tool against container mosquitoes in field trials in different habitats confronted by mosquito control personnel. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Allometria da palmeira babaçu em um agroecossistema de derruba-e-queima na periferia este da Amazônia

OpenAIRE

Gehring,Christoph; Zelarayán,Marcelo Luís C.; Almeida,Rosângela B.; Moraes,Flávio Henrique R.

2011-01-01

A palmeira babaçu (Attalea speciosa C.Martius, Arecaceae) tem grande importância socioeconômica e ecológica em grande parte da área tropical brasileira, especialmente em áreas degradadas por queimadas freqüentes na Amazônia. No entanto, ainda pouco se sabe sobre as características ecológicas desta espécie-chave. Este estudo investiga a alometria do babaçu com o objetivo de estabelecer uma metodologia eficiente na estimativa da biomassa aérea de palmeiras juvenis e adultas e para um melhor ent...

field control of peridomestic mosquitoes of medical importance

African Journals Online (AJOL)

2004-02-18

Feb 18, 2004 ... less potent than the aqueous extract under field conditions. The significance of ... Many plants in the family Phytollacaceae are known to be. 4°C until needed. ..... SAS User's guide: Statistics, version 5 SAS institute, to gravid ...

Gelatin/piassava composites treated by Electron Beam Radiation

International Nuclear Information System (INIS)

Takinami, Patricia Yoko Inamura; Shimazaki, Kleber; Moura, Esperidiana Augusta Barretos de; Mastro, Nelida Lucia del; Colombo, Maria Aparecida

2010-01-01

Piassava (Attalea funifera Mart) fiber has been investigated as reinforcement for polymer composites with potential for practical applications. The purpose of the present work was to assess the behavior of specimens of piassava fiber and gelatin irradiated with electron beam at different doses and percentage. The piassava/gelatin specimens were made with 5 and 10% (w/w) piassava fiber, gelatin 25% (w/w), glycerin as plasticizer and acrylamide as copolymer. The samples were irradiated up to 40 kGy using an electron beam accelerator, at room temperature in presence of air. Preliminary results showed mechanical properties enhancement with the increase in radiation dose. (author)

Search Results | Page 23 | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

Results 221 - 230 of 902 ... ... with low levels of economic resources and how benefits derived from that access are distributed. ... Entomological impact and social participation in dengue control : a cluster randomized trial in Fortaleza, Brazil ... disease based on peridomestic animal management : an eco-bio-social perspective.

Preparation nanowhiskers pulp from residue of palm fiber Attalea funifera Martius

International Nuclear Information System (INIS)

Silva, J.B.A. da; Miranda, C.S.; Jose, N.M.; Vargas, F.P.; Druzian, J.I.

2010-01-01

The residue from piassava fiber is higher in cellulose and lignin. This study aimed to extract the pulp and the development of methodology for preparation nanowhiskers from residue fiber. The first step extraction of cellulose, the second step to obtain the nanoparticles by acid hydrolysis (H 2 SO 4 ). The samples were characterized by: SEM, chemical composition, TGA, FTIR and XRD. The XRD result shows that cellulose is of type I and TGA shows two events at 54 deg C and 370 deg C attributed to mass loss of water and cellulose, respectively. After hydrolysis, X-ray diffraction showed an intense reflection 2θ= 22.3 deg and an increase in the degree of crystallinity to 70% which is an indication of the formation of nanowhiskers. (author)

Absence of domestic triatomine colonies in an area of the coastal region of Ecuador where Chagas disease is endemic

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Mario J Grijalva

2010-08-01

Full Text Available Rhodnius ecuadoriensis is considered the second most important vector of Chagas disease in Ecuador. It is distributed across six of the 24 provinces and occupies intradomiciliary, peridomiciliary and sylvatic habitats. This study was conducted in six communities within the coastal province of Guayas. Triatomine searches were conducted in domestic and peridomestic habitats and bird nests using manual searches, live-bait traps and sensor boxes. Synantrhopic mammals were captured in the domestic and peridomestic habitats. Household searches (n = 429 and randomly placed sensor boxes (n = 360 produced no live triatomine adults or nymphs. In contrast, eight nymphs were found in two out of six searched Campylorhynchus fasciatus (Troglodytidae nests. Finally, Trypanosoma cruzi DNA was amplified from the blood of 10% of the 115 examined mammals. Environmental changes in land use (intensive rice farming, mosquito control interventions and lack of intradomestic adaptation are suggested among the possible reasons for the lack of domestic triatomine colonies.

Phlebotomine Vector Ecology in the Domestic Transmission of American Cutaneous Leishmaniasis in Chaparral, Colombia

Science.gov (United States)

Ferro, Cristina; Marín, Dairo; Góngora, Rafael; Carrasquilla, María C.; Trujillo, Jorge E.; Rueda, Norma K.; Marín, Jaime; Valderrama-Ardila, Carlos; Alexander, Neal; Pérez, Mauricio; Munstermann, Leonard E.; Ocampo, Clara B.

2011-01-01

Phlebotomine vector ecology was studied in the largest recorded outbreak of American cutaneous leishmaniasis in Colombia in 2004. In two rural townships that had experienced contrasting patterns of case incidence, this study evaluated phlebotomine species composition, seasonal abundance, nocturnal activity, blood source, prevalence of Leishmania infection, and species identification. CDC miniature light traps were used to trap the phlebotomines. Traps were set indoors, peridomestically, and in woodlands. Natural infection was determined in pools by polymerase chain reaction–Southern blot, and blood sources and species identification were determined by sequencing. Large differences were observed in population abundance between the two townships evaluated. Lutzomyia longiflocosa was the most abundant species (83.1%). Abundance was higher during months with lower precipitation. Nocturnal activity was associated with human domestic activity. Blood sources identified were mainly human (85%). A high prevalence of infection was found in L. longiflocosa indoors (2.7%) and the peridomestic setting (2.5%). L. longiflocosa was responsible for domestic transmission in Chaparral. PMID:22049038

An entomoepidemiological investigation of Chagas disease in the state of Ceará, Northeast Region of Brazil

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Carolina Fausto de Souza Coutinho

2014-04-01

Full Text Available The seroprevalence of Chagas disease in humans and the presence of triatomines were investigated in a rural locality in the State of Ceará, Brazil, an historically endemic region. Approximately 80% of the surveyed residents agreed to undergo serological tests. Intradomestic and peridomestic environments were searched for triatomines in both the dry and rainy seasons. The prevalence rate of Chagas disease was 1.2% and the majority of individuals confirmed with the disease over 50 years of age. A total of 761 specimens of triatomines were captured, most of which were from colonies composed of nymphs and adult bugs, and the majority of specimens were obtained in the dry season. Triatoma brasiliensis was the predominant species. Analysis using light microscopy revealed that 28.6% of the insects were Trypanosoma cruzi positive. Results suggest that peridomestic man-made structures, such as animal shelters, improper storage of timber and uninhabited dwellings contribute to the high rate of triatomine infestation in the area.

Phlebotomine vector ecology in the domestic transmission of American cutaneous leishmaniasis in Chaparral, Colombia.

Science.gov (United States)

Ferro, Cristina; Marín, Dairo; Góngora, Rafael; Carrasquilla, María C; Trujillo, Jorge E; Rueda, Norma K; Marín, Jaime; Valderrama-Ardila, Carlos; Alexander, Neal; Pérez, Mauricio; Munstermann, Leonard E; Ocampo, Clara B

2011-11-01

Phlebotomine vector ecology was studied in the largest recorded outbreak of American cutaneous leishmaniasis in Colombia in 2004. In two rural townships that had experienced contrasting patterns of case incidence, this study evaluated phlebotomine species composition, seasonal abundance, nocturnal activity, blood source, prevalence of Leishmania infection, and species identification. CDC miniature light traps were used to trap the phlebotomines. Traps were set indoors, peridomestically, and in woodlands. Natural infection was determined in pools by polymerase chain reaction-Southern blot, and blood sources and species identification were determined by sequencing. Large differences were observed in population abundance between the two townships evaluated. Lutzomyia longiflocosa was the most abundant species (83.1%). Abundance was higher during months with lower precipitation. Nocturnal activity was associated with human domestic activity. Blood sources identified were mainly human (85%). A high prevalence of infection was found in L. longiflocosa indoors (2.7%) and the peridomestic setting (2.5%). L. longiflocosa was responsible for domestic transmission in Chaparral.

Wingbeat frequency-sweep and visual stimuli for trapping male Aedes aegypti (Diptera: Culicidae)

Science.gov (United States)

Combinations of female wingbeat acoustic cues and visual cues were evaluated to determine their potential for use in male Aedes aegypti (L.) traps in peridomestic environments. A modified Centers for Disease control (CDC) light trap using a 350-500 Hz frequency-sweep broadcast from a speaker as an a...

Comparative Properties of Amazonian Oils Obtained by Different Extraction Methods

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Cláudio Galuppo Diniz

2011-07-01

Full Text Available Pequi (Caryocar brasiliense Camb., babaçu (Orbignya phalerata Mart., buriti (Mauritia flexuosa, and passion fruit (Passiflora edulis oils were studied to determine their antibacterial, antioxidant and cytotoxic activities, as well as their total phenol and carotenoid contents. The fatty acid contents were determined by GC-MS. The three types of passion fruit oils studied were refined, cold pressed or extracted from seeds in a Soxhlet apparatus. The oils thus obtained showed differences in antioxidant activity and carotenoid content, but were similar in regard to total phenols. Buriti and pequi had the highest carotenoid contents, while refined and cold pressed passion fruit oil displayed the highest antioxidant activity. Pequi oil was the only oil to display antibacterial and cytotoxic activity.

Assessing peridomestic entomological factors as predictors for Lyme disease

Science.gov (United States)

Connally, N.P.; Ginsberg, H.S.; Mather, T.N.

2006-01-01

The roles of entomologic risk factors, including density of nymphal blacklegged ticks (Ixodes scapularis), prevalence of nymphal infection with the etiologic agent (Borrelia burgdorferi), and density of infected nymphs, in determining the risk of human Lyme disease were assessed at residences in the endemic community of South Kingstown, RI. Nymphs were sampled between May and July from the wooded edge around 51 and 47 residential properties in 2002 and 2003, respectively. Nymphs were collected from all residences sampled. Tick densities, infection rates, and densities of infected nymphs were all significantly higher around homes reporting Lyme disease histories in 2003, while only infection rates were significantly higher in 2002. However, densities of infected nymphs did not significantly predict the probability of Lyme disease at a residence (by logistic regression) in either year. There were no significant differences in entomologic risk factors between homes with state-confirmed Lyme disease histories and homes with self-reported cases (not reported to the state health department). Therefore, although entomologic risk factors tended to be higher at residences with cases of Lyme disease, entomological indices, in the absence of human behavior measures, were not useful predictors of Lyme disease at the scale of individual residences in a tick-endemic community.

Urbanization and geographic expansion of zoonotic arboviral diseases: mechanisms and potential strategies for prevention

OpenAIRE

Weaver, Scott C.

2013-01-01

Arthropod-borne viruses (arboviruses) mainly infect people via direct spillover from enzootic cycles. However, dengue, chikungunya, and yellow fever viruses have repeatedly initiated urban transmission cycles involving human amplification and peridomestic mosquito vectors to cause major epidemics. Here, I review these urban emergences and potential strategies for their prevention and control.

Topographic separation of two sympatric palms in the central Amazon - does dispersal play a role?

Science.gov (United States)

Gomes de Freitas, Cintia; Capellotto Costa, Flávia Regina; Svenning, Jens-Christian; Balslev, Henrik

2012-02-01

Despite broadly overlapping geographic distributions in the central Amazon basin, two congeneric palm species (Attalea attaleoides and Attalea microcarpa) have topographically separated distributions on a local scale in Reserva Ducke near Manaus. Our aim here was to determine if this local scale separation can be linked to (1) seedling stage specialization to different habitat conditions of the two species, and/or (2) environmentally-controlled seed dispersal. We assessed the role of these potential drivers by mapping the local distribution of the two species over a 25-km2 grid and testing for correlation to seed removal and seed germination patterns using seed sowing experiments. 360 seeds of each species were sown in 30 uniformly distributed plots (12 seeds of each species in each plot), and seed removal and germination were subsequently monitored. Adult populations of the two species showed opposite distribution patterns linked to topography. However, there was little evidence for specialization to different habitat conditions at the seedling stage: after 11 months, 26.1% of seeds of A. microcarpa had germinated along the entire topographic gradient, albeit with a tendency toward higher germination in more inclined areas. For A. attaleoides, only 2.2% seeds had germinated, and again along the entire topographic gradient. In contrast, there was evidence for environmentally-controlled seed dispersal: for both species, seed removal was higher in flat areas. Presence of adults did not affect germination or seed removal. Our results suggest that topographically differentiated distributions of A. attaleoides and A. microcarpa may be reinforced by steep slope avoidance by their seed dispersers. A direct environmental control mechanism remains to be identified to explain the consistent topographic associations, but our results show that this mechanism does not work at the seed germination stage.

Characterization of Guinea Pig Antibody Responses to Salivary Proteins of Triatoma infestans for the Development of a Triatomine Exposure Marker

Czech Academy of Sciences Publication Activity Database

Dorňáková, Veronika; Salazar-Sanchez, R.; Borrini-Mayori, K.; Carrion-Navarro, O.; Levy, M.Z.; Schaub, G. A.; Schwarz, Alexandra

2014-01-01

Roč. 8, č. 4 (2014), e2783 ISSN 1935-2735 R&D Projects: GA ČR GPP302/11/P798; GA MŠk LH12002 Institutional support: RVO:60077344 Keywords : detecting peridomestic populatons * Chagas disease transmission * vector control Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.446, year: 2014

Ife Journal of Science - Vol 6, No 1 (2004)

African Journals Online (AJOL)

Field control of peridomestic mosquitoes of medical importance with extracts of Petiveria alliacea L. EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. TA Adebayo, JI Olaifa, AJ Akintola, AO Ojo, 6-9. http://dx.doi.org/10.4314/ijs.v6i1.32114 ...

Blood meal sources of wild and domestic Triatoma infestans (Hemiptera: Reduviidae) in Bolivia: connectivity between cycles of transmission of Trypanosoma cruzi.

Science.gov (United States)

Buitrago, Rosio; Bosseno, Marie-France; Depickère, Stéphanie; Waleckx, Etienne; Salas, Renata; Aliaga, Claudia; Barnabé, Christian; Brenière, Simone Frédérique

2016-04-18

Chagas disease is a major public health problem in Latin America. Its etiologic agent, Trypanosoma cruzi, is mainly transmitted through the contaminated faeces of blood-sucking insects called triatomines. Triatoma infestans is the main vector in various countries in South America and recently, several foci of wild populations of this species have been described in Bolivia and other countries. These wild populations are suspected of affecting the success of insecticide control campaigns being carried out in South America. To assess the risk that these T. infestans populations pose to human health, it is helpful to determine blood meal sources. In the present work, blood meals were identified in various Bolivian wild T. infestans populations and in three specific areas, in both wild and intra-peridomestic populations to assess the links between wild and domestic cycles of T. cruzi transmission. PCR-HDA and sequencing of Cytb gene were used to identify these blood meal sources. Fourteen vertebrate species were identified as wild blood meal sources. Of those, the most prevalent species were two Andean endemic rodents, Octodontomys gliroides (36%) and Galea musteloides (30%), while humans were the third most prevalent source (18.7%). Of 163 blood meals from peridomestic areas, more than half were chickens, and the others were generally domestic animals or humans. Interestingly, blood from wild animals was identified in triatomines captured in the peridomestic and domestic environment, and blood from domestic animals was found in triatomines captured in the wild, revealing links between wild and domestic cycles of T. cruzi transmission. The current study suggests that wild T. infestans attack humans in the wild, but is also able to bite humans in domestic settings before going back to its natural environment. These results support the risk to human health posed by wild populations of T. infestans.

A survey on Triatoma dimidiata in an urban area of the province of Heredia, Costa Rica

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Rodrigo Zeledón

2005-10-01

Full Text Available Triatoma dimidiata has been found in several cities and towns of those countries where the insect is a domestic or peridomestic pest. In Central America, urban infestations occur in the capitals of at least five countries. During 2001 and 2002 a survey was carried out in the county of San Rafael, Heredia province, located 15 km northwest of San José, capital of Costa Rica, in order to determine the degree of infestation by T. dimidiata in an entire city block. Six peridomestic colonies of the insect were detected in the backyards of eight households. The ecotopes occupied by the insects consisted of store rooms with old objects, wood piles or firewood, and chicken coops. A total of 1917 insects were found in the six foci, during two sampling periods, and a mean infection rate by Trypanosoma cruzi of 28.4% was found in 1718 insects examined. The largest colony found in one of the households yielded 872 insects that were thriving mainly at the expenses of two dogs. Opossums and adult insects were common visitors of the houses and it became evident that this marsupial is closely related to the peridomestic cycle of the Chagas disease agent. Lack of colonization of the insect inside the human dwellings is explained by the type of construction and good sanitary conditions of the houses, in contrast to the situation in most peridomiciliary areas. Stomach blood samples from the insects showed that the main hosts were, in order of decreasing frequency: rodents, dogs, fowl, humans, opossums, and cats. The fact that no indication of infection with Chagas disease could be detected in the human occupants of the infested houses, vis a vis the high infection rate in dogs, is discussed.

Canine visceral leishmaniasis in Barra de Guaratiba, Rio de Janeiro, Brazil: assessment of risk factors

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Cabrera Maria Alice A.

2003-01-01

Full Text Available Barra de Guaratiba is a coastal area of the city of Rio de Janeiro where American visceral leishmaniasis (AVL is endemic. Although control measures including killing of dogs and use of insecticides have been applied at this locality, the canine seroprevalence remains at 25% and during 1995 and 1997 eight autochthonous human cases were notified. In order to evaluate factors related to the increase of the risk for Leishmania (Leishmania chagasi infection in dogs we have screened 365 dogs by anti-Leishmania immunofluorescent antibody test (IFAT and captured sandflies in the domestic and peridomestic environment. Some variables related to the infection were assessed by uni- and multivariate analysis. The distance of the residence from the forest border, its altitude and the presence of the opossum Didelphis marsupialis in the backyard, were found predictor factors for L. (L. chagasi infection in dogs in Barra de Guaratiba. The presence of Lutzomyia longipalpis in the peridomestic environment indicates the possibility of appearence of new human cases. Our data also suggest the presence of a sylvatic enzootic cycle at this locality.

Urbanization and geographic expansion of zoonotic arboviral diseases: mechanisms and potential strategies for prevention.

Science.gov (United States)

Weaver, Scott C

2013-08-01

Arthropod-borne viruses (arboviruses) mainly infect people via direct spillover from enzootic cycles. However, dengue, chikungunya, and yellow fever viruses have repeatedly initiated urban transmission cycles involving human amplification and peridomestic mosquito vectors to cause major epidemics. Here, I review these urban emergences and potential strategies for their prevention and control. Copyright © 2013 Elsevier Ltd. All rights reserved.

Toxocara cati (Nematoda: Ascarididae in Didelphis albiventris (Marsupialia: Didelphidae from Brazil: a case of pseudoparasitism

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Hudson Alves Pinto

2014-12-01

Full Text Available Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.

Preparation nanowhiskers pulp from residue of palm fiber Attalea funifera Martius; Preparacao de nanowhiskers de celulose a partir do residuo da fibra de piacava da palmeira Attalea funifera Martius

Energy Technology Data Exchange (ETDEWEB)

Silva, J.B.A. da; Miranda, C.S.; Jose, N.M.; Vargas, F.P.; Druzian, J.I., E-mail: janiabet@yahoo.com.b [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil)

2010-07-01

The residue from piassava fiber is higher in cellulose and lignin. This study aimed to extract the pulp and the development of methodology for preparation nanowhiskers from residue fiber. The first step extraction of cellulose, the second step to obtain the nanoparticles by acid hydrolysis (H{sub 2}SO{sub 4}). The samples were characterized by: SEM, chemical composition, TGA, FTIR and XRD. The XRD result shows that cellulose is of type I and TGA shows two events at 54 deg C and 370 deg C attributed to mass loss of water and cellulose, respectively. After hydrolysis, X-ray diffraction showed an intense reflection 2{theta}= 22.3 deg and an increase in the degree of crystallinity to 70% which is an indication of the formation of nanowhiskers. (author)

Indoor-Breeding of Aedes albopictus in Northern Peninsular Malaysia and Its Potential Epidemiological Implications

OpenAIRE

Dieng, Hamady; Saifur, Rahman G. M.; Hassan, Ahmad Abu; Salmah, M. R. Che; Boots, Michael; Satho, Tomomitsu; Jaal, Zairi; AbuBakar, Sazaly

2010-01-01

BACKGROUND: The mosquito Ae. albopictus is usually adapted to the peri-domestic environment and typically breeds outdoors. However, we observed its larvae in most containers within homes in northern peninsular Malaysia. To anticipate the epidemiological implications of this indoor-breeding, we assessed some fitness traits affecting vectorial capacity during colonization process. Specifically, we examined whether Ae. albopictus exhibits increased survival, gonotrophic activity and fecundity du...

The eco-epidemiology of Triatoma infestans in the temperate Monte Desert ecoregion of mid-western Argentina

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Ana Laura Carbajal-de-la-Fuente

Full Text Available BACKGROUND The eco-epidemiological status of Chagas disease in the Monte Desert ecoregion of western Argentina is largely unknown. We investigated the environmental and socio-demographic determinants of house infestation with Triatoma infestans, bug abundance, vector infection with Trypanosoma cruzi and host-feeding sources in a well-defined rural area of Lavalle Department in the Mendoza province. METHODS Technical personnel inspected 198 houses for evidence of infestation with T. infestans, and the 76 houses included in the current study were re-inspected. In parallel with the vector survey, an environmental and socio-demographic survey was also conducted. Univariate risk factor analysis for domiciliary infestation was carried out using Firth penalised logistic regression. We fitted generalised linear models for house infestation and bug abundance. Blood meals were tested with a direct ELISA assay, and T. cruzi infection was determined using a hot-start polymerase chain reaction (PCR targeting the kinetoplast minicircle (kDNA-PCR. FINDINGS The households studied included an aged population living in precarious houses whose main economic activities included goat husbandry. T. infestans was found in 21.2% of 198 houses and in 55.3% of the 76 re-inspected houses. Peridomestic habitats exhibited higher infestation rates and bug abundances than did domiciles, and goat corrals showed high levels of infestation. The main host-feeding sources were goats. Vector infection was present in 10.2% of domiciles and 3.2% of peridomiciles. Generalised linear models showed that peridomestic infestation was positively and significantly associated with the presence of mud walls and the abundance of chickens and goats, and bug abundance increased with the number of all hosts except rabbits. MAIN CONCLUSIONS We highlight the relative importance of specific peridomestic structures (i.e., goat corrals and chicken coops associated with construction materials and host

Factors associated with the occurrence of Triatoma sordida (Hemiptera: Reduviidae in rural localities of Central-West Brazil

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Juliana Chedid Nogared Rossi

2015-04-01

Full Text Available This study estimates the factors of artificial environments (houses and peridomestic areas associated with Triatoma sordida occurrence. Manual searches for triatomines were performed in 136 domiciliary units (DUs in two rural localities of Central-West Brazil. For each DU, 32 structural, 23 biotic and 28 management variables were obtained. Multiple logistic regression analysis was performed in order to identify statistically significant variables associated with occurrence of T. sordida in the study areas. A total of 1,057 specimens (99% in peridomiciles, mainly chicken coops of T. sordida were collected from 63 DUs (infestation: 47%; density: ~8 specimens/DU; crowding: ~17 specimens/infested DU; colonisation: 81%. Only six (0.6% out of 945 specimens examined were infected with Trypanosoma cruzi. The final adjusted logistic regression model indicated that the probability of T. sordida occurrence was higher in DU with wooden chicken coops, presence of > 30 animals in wooden corrals, presence of wood piles and presence of food storeroom. The results show the persistence of T. sordida in peridomestic habitats in rural localities of Central-West Brazil. However, the observed low intradomestic colonisation and minimal triatomine infection rates indicate that T. sordida has low potential to sustain high rates of T. cruzi transmission to residents of these localities.

Trypanosoma cruzi strains from triatomine collected in Bahia and Rio Grande do Sul, Brazil

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Aline Rimoldi Ribeiro

2014-04-01

Full Text Available OBJECTIVE Collection of triatomines in domestic, peridomestic and sylvatic environments in states of Bahia and Rio Grande do Sul, Northeastern and Southern Brazil respectively, and isolation of Trypanosoma cruzi strains. METHODS First, the captured triatomines were identified using insect identification keys, then their intestinal content was examined by abdominal compression, and the samples containing trypanosomatid forms were inoculated in LIT medium and Swiss mice. RESULTS Six triatomine species were collected in cities in Bahia, namely Panstrongylus geniculatus (01, Triatoma melanocephala (11, T. lenti (94, T. pseudomaculata (02, T. sherlocki (26 and T. sordida (460, and two in cities in Rio Grande do Sul, namely T. circummaculata (11 and T. rubrovaria (115. Out of the specimens examined, T. cruzi was isolated from 28 triatomine divided into four different species: T. melanocephala (one, T. lenti (one, T. rubrovaria (16 and T. sordida (10. Their index of natural infection by T. cruzi was 6.4%. CONCLUSIONS The isolation of T. cruzi strains from triatomines found in domestic and peridomestic areas shows the potential risk of transmission of Chagas disease in the studied cities. The maintenance of those T. cruzi strains in laboratory is intended to promote studies that facilitate the understanding of the parasite-vector-host relationship.

Ecology of rodent-associated hantaviruses in the Southern Cone of South America: Argentina, Chile, Paraguay, and Uruguay.

Science.gov (United States)

Palma, R Eduardo; Polop, Jaime J; Owen, Robert D; Mills, James N

2012-04-01

Thirteen hantavirus genotypes, associated with at least 12 sigmodontine reservoir rodents, have been recognized in the four countries that represent the Southern Cone of South America. Host-virus relationships are not as well defined as in North America; several Southern Cone hantaviruses appear to share a common host and some viruses do not occur throughout the range of their host. Although hantavirus-host relationships in the Southern Cone are less strictly concordant with the single-host-single-virus pattern reported elsewhere, recent studies suggest that much of the ambiguity may result from an incomplete understanding of host and hantavirus systematics. Although some Southern Cone host species are habitat generalists, some sympatric species are habitat specialists, helping to explain how some strict host-virus pairings may be maintained. In some cases, host population densities were higher in peridomestic habitats and prevalence of hantavirus infection was higher in host populations in peridomestic habitats. Seasonal and multiyear patterns in climate and human disturbance affect host population densities, prevalence of infection, and disease risk to humans. Unusually high hantavirus antibody prevalence in indigenous human populations may be associated with frequent and close contact with host rodents. Ongoing studies are improving our understanding of hantavirus-host ecology and providing tools that may predict human risk.

One Health Interactions of Chagas Disease Vectors, Canid Hosts, and Human Residents along the Texas-Mexico Border.

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Melissa N Garcia

2016-11-01

Full Text Available Chagas disease (Trypanosoma cruzi infection is the leading cause of non-ischemic dilated cardiomyopathy in Latin America. Texas, particularly the southern region, has compounding factors that could contribute to T. cruzi transmission; however, epidemiologic studies are lacking. The aim of this study was to ascertain the prevalence of T. cruzi in three different mammalian species (coyotes, stray domestic dogs, and humans and vectors (Triatoma species to understand the burden of Chagas disease among sylvatic, peridomestic, and domestic cycles.To determine prevalence of infection, we tested sera from coyotes, stray domestic dogs housed in public shelters, and residents participating in related research studies and found 8%, 3.8%, and 0.36% positive for T. cruzi, respectively. PCR was used to determine the prevalence of T. cruzi DNA in vectors collected in peridomestic locations in the region, with 56.5% testing positive for the parasite, further confirming risk of transmission in the region.Our findings contribute to the growing body of evidence for autochthonous Chagas disease transmission in south Texas. Considering this region has a population of 1.3 million, and up to 30% of T. cruzi infected individuals developing severe cardiac disease, it is imperative that we identify high risk groups for surveillance and treatment purposes.

Control of dengue vector by the sterile insect technique considering logistic recruitment

International Nuclear Information System (INIS)

Esteva, L.; Yang, H.M.

2006-01-01

We propose a mathematical model to assess the effects of irradiated male insects introduction in a previously infested region, taking into account the logistic recruitment of sterile male insects. The release of sterile male insects aims to displace gradually the natural (or wild) insect from the habitat. We discuss the suitability of this release technique when applied to peridomestic adapted Aedes aegypyti mosquitoes which are transmitters of Yellow Fever and Dengue disease. (author)

Control of dengue vector by the sterile insect technique considering logistic recruitment

Energy Technology Data Exchange (ETDEWEB)

Esteva, L. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico). Facultad de Ciencias. Dept. de Matematicas; Lab-Epifisma, Mexico, D.F. (Mexico); Yang, H.M. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Matematica, Estatistica e Ciencia da Computacao. Dept. de Matematica Aplicada; Lab-Epifisma, Campinas, SP (Brazil)

2006-07-01

We propose a mathematical model to assess the effects of irradiated male insects introduction in a previously infested region, taking into account the logistic recruitment of sterile male insects. The release of sterile male insects aims to displace gradually the natural (or wild) insect from the habitat. We discuss the suitability of this release technique when applied to peridomestic adapted Aedes aegypyti mosquitoes which are transmitters of Yellow Fever and Dengue disease. (author)

Triatomines in dwellings and outbuildings in an endemic area of Chagas disease in northeastern Brazil

OpenAIRE

Lima, Antonio Fernando Rodrigues; Jeraldo, Veronica de Lourdes Sierpe; Silveira, Maxwell Souza; Madi, Rubens Riscala; Santana, Thiago Bicudo Krempel; Melo, Cláudia Moura de

2012-01-01

INTRODUCTION: The present study identified the triatomines collected in intra and peri-domestic environments, observed the occurrence of Trypanosoma cruzi infection in triatomines and correlated this information with housing conditions and the fauna associated with the rural areas of the City of Itabaianinha, located in the State of Sergipe, Brazil. METHODS: Quarterly visits were conducted between March 2009 and March 2010, and the homes to be visited for the active search of insects were det...

Leptospira Contamination in Household and Environmental Water in Rural Communities in Southern Chile

OpenAIRE

Muñoz-Zanzi, Claudia; Mason, Meghan R.; Encina, Carolina; Astroza, Angel; Romero, Alex

2014-01-01

Leptospirosis is a zoonosis of global distribution that affects tropical and temperate areas. Under suitable conditions, Leptospira can survive in water and soil and contribute to human and animal infections. The objective of this study was to describe the presence of pathogenic Leptospira in peri-domestic water samples from rural households in southern Chile. Water samples, including puddles, containers, animal troughs, rivers, canals, and drinking water were collected from 236 households an...

Norcantharidin, Derivative of Cantharidin, for Cancer Stem Cells

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Chen-Hsi Hsieh

2013-01-01

Full Text Available Cancer stem cells (CSCs existing in human cancers have been demonstrated to be a major cause of cancer treatment resistance, invasion, metastasis, and relapse. Self-renewal pathways, Wnt/β-catenin, Sonic hedgehog (Shh, and the Notch signaling pathway play critical roles in developing CSCs and lead to angiogenesis, migration, invasion, and metastasis. Multidrug resistance (MDR is an unfavorable factor causing the failure of treatments against cancer cells. The most important and thoroughly studied mechanism involved in MDR is the active efflux of chemotherapeutic agents through membrane drug transporters. There is growing evidence that Norcantharidin (NCTD, a water-soluble synthetic small molecule derivative of naturally occurring cantharidin from the medicinal insect blister beetle (Mylabris phalerata Pallas, is capable of chemoprevention and tumor inhibition. We summarize investigations into the modulation of self-renewal pathways and MDR in CSCs by NCTD. This review may aid in further investigation of using NCTD to develop more effective strategies for cancer treatment to reduce resistance and recurrence.

Oligarchic forests of economic plants in amazonia: utilization and conservation of an important tropical resource.

Science.gov (United States)

Peters, C M; Balick, M J; Kahn, F; Anderson, A B

1989-12-01

Tropical forests dominated by only one or two tree species occupy tens of millions of hectares in Ammonia In many cases, the dominant species produce fruits, seeds, or oils of economic importance. Oligarchic (Gr. oligo = few, archic = dominated or ruled by) forests of six economic species, i. e., Euterpe oleracea, Grias peruviana, Jessenia bataua, Mauritia flexuosa, Myrciaria dubia, and Orbignya phalerata, were studied in Brazil and Peru Natural populations of these species contain from 100 to 3,000 conspecific adult trees/ha and produce up to 11.1 metric tons of fruit/hd/yr. These plant populations are utilized and occasionally managed, by rural inhabitants in the region. Periodic fruit harvests, if properly controlled have only a minimal impact on forest structure and function, yet can generate substantial economic returns Market-oriented extraction of the fruits produced by oligarchic forests appears to represent a promising alternative for reconciling the development and conservation of Amazonian forests.

Association of the "IUCN vulnerable "spiny rat Clyomys bishopi (Rodentia:Echimyidaewith palm trees and armadillo burrows in southeastern Brazil

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Adriana A Bueno

2004-12-01

Full Text Available The globally vulnerable Clyomys bishopi ,a semi-fossorial and colonial rodent,is apparently limited to cerrado (savannah-like vegetationphysiognomies in São Paulo State,Brazil.The aim of the study was to verify whether the presence of C.bishopi is associated to the occurrence of palm trees (Attalea gearensis, Syagrus loefgrenii and armadillo burrows.Thirty six quadrats were placed in different physiognomies of cerrado vegetation at Itirapina Ecological Station,southeastern Brazil to survey the number of C.bishopi burrows of individuals of palm trees and burrows of armadillos.There was a strong dependence and association between the number of C.bishopi burrows and all measured variables (Contingency tables and Spearman rank correlations.It is suggested that this rodent can be found in great numbers where palm trees are abundant.The use of armadillo burrows possibly makes the movement of the rodents easier inside their own galleries.Rev.Biol. Trop. 52(4:1009-1011.Epub 2005 Jun 24.El roedor colonial Clyomys bishopi está aparentemente limitado a vegetación de semi-sabana (cerradoen el estado de São Paulo,Brasil.El objetivo de este estudio fue verificar si la presencia de C.bishopi está asociada a la individuos de las palmeras Attalea gearensis,Syagrus loefgrenii y madrigueras de armadillos.El estudio fue realizado en la Estación Ecológica de Itirapina,en el sureste de Brasil.Treinta y seis cuadrantes fueron dispuestos en diferentes fisionomías del la vegetación del cerrado para encuestar el número de madrigueras de C.bishopi, árboles individuales de palma y madrigueras de armadillos.Se calcularon tablas de contingencia y correlaciones de Sperman para evaluar, respectivamente, la dependencia y asociación entre el número de madrigueras de C.bishopi y las otras variables.Se encontró una fuerte dependencia y asociación entre el número de madrigueras de C.bishopi y todas las variables medidas.Esto sugiere que este roedor alcanza grandes

Presence of Triatominae (Hemiptera, Reduviidae and Risk of Transmission of Chagas Disease in Colima, México

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Espinoza-Gómez Francisco

2002-01-01

Full Text Available With the purpose of evaluating the risk of transmission of the Chagas disease in the State of Colima, México, an entomological survey was performed to obtain triatominae and the rate of infection by Trypanosoma cruzi determined by examination of its dejections. Two hundred eighteen houses located in 16 villages were sampled. In each house the intradomestic and peridomestic habitats were examined by the man-hour-house method, sensor boxes and mouse-baited traps. Also, 12 silvatic places were explored around the same areas using the same techniques as the ones sampled. In total, 456 specimens were captured, of which 139 correspond to Triatoma phyllosoma pallidipennis; 80 to T. p. longipennis; one specimen of T. dimidiata and 236 nymphs of Triatoma sp. Two hundred ninety seven insects were captured in the intradomestic habitat, 132 in the peridomestic and 26 in the silvatic. The index of positive houses was 27%, located in the central area of the state. The rate of natural infection with T. cruzi showed 25.6%. This results confirmed the presence of two important vectors of the Chagas disease in Colima. Its preference for the domestic habitat and its high levels of natural infection with T. cruzi suggested the existence of a significant risk for its transmission in this area of the country.

Environmental factors associated with American cutaneous leishmaniasis in a new Andean focus in Colombia.

Science.gov (United States)

Ocampo, C B; Ferro, M C; Cadena, H; Gongora, R; Pérez, M; Valderrama-Ardila, C H; Quinnell, R J; Alexander, N

2012-10-01

To evaluate the environmental and ecological factors associated with Leishmania transmission and vector abundance in Chaparral, Tolima-Colombia. First, we compared the ecological characteristics, abundance of phlebotomies and potential reservoir hosts in the peridomestic environment (100 m radius) of randomly selected houses, between two townships with high and low cutaneous leishmaniasis incidence. Second, we examined peridomestic correlates of phlebotomine abundance in all 43 houses in the higher risk township. The high transmission township had higher coverage of forest (23%vs. 8.4%) and shade coffee (30.7%vs. 11%), and less coffee monoculture (16.8%vs. 26.2%) and pasture (6.3%vs. 12.3%), compared to the low transmission township. Lutzomyia were more abundant in the high transmission township 2.5 vs. 0.2/trap/night. Lutzomyia longiflocosa was the most common species in both townships: 1021/1450 (70%) and 39/80 (49%). Numbers of potential wild mammal reservoirs were small, although four species were found to be infected with Leishmania (Viannia) spp. In the high transmission township, the overall peridomiciliary capture rate of L. longiflocosa was 1.5/trap/night, and the abundance was higher in houses located nearer to forest (ρ = -0.30, P = 0.05). The findings are consistent with a domestic transmission cycle with the phlebotomies dependent on dense vegetation near the house. © 2012 Blackwell Publishing Ltd.

First Case of Natural Infection in Pigs: Review of Trypanosoma cruzi Reservoirs in Mexico

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Paz María Salazar-Schettino

1997-07-01

Full Text Available An epidemiological research project was performed in the State of Morelos including collection of samples for blood smears and culture, serological tests, and xenodiagnoses from a total of 76 domestic and peridomestic mammals. Two strains of Trypanosoma cruzi were isolated by haemocultures; one from a pig (Sus scrofa, the first case of natural infection reported in Mexico, and the other from a dog (Canis familiaris. This study summarizes current information in Mexico concerning confirmed reservoirs of T. cruzi

Myxomycetes em Palmeiras (Arecaceae Myxomycetes on palm trees (Arecaceae

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Maria Helena Alves

1996-07-01

Full Text Available As palmeiras oferecem um ecossistema especializado que abriga organismos variados, incluindo Myxomycetes. Este trabalho relata doze espécies de Myxomycetes encontradas em folhas mortas, espata e estipe de Acrocomia intumescens Drude (macaúba, Copernicea prunifera (Mill. H. E. Moore (carnaúba, Mauritia flexuosa Mart, (buriti e Orbygnia phalerata Mart, (babaçu. Constitui-se área de coleta o Município do Crato, Ceará, Nordeste do Brasil (7º 30'00" S, 39º 00' 00" W, 400-1200 m de altitude. Coletas aleatórias foram efetuadas e as frutificações foram pesquisadas em órgãos vivos ou mortos das palmeiras. Exsicatas foram depositadas no Herbário UFP (Departamento de Botânica da Universidade Federal de Pernambuco, Recife - PE, Brasil. As espécies registradas pertencem aos gêneros Ceratiomyxa (1, Dictydium (1, Arcyria (1, Hemitrichia (1, Badhamia (1, Fuligo (1, Physarum (3, Stemonitis (2 e Comatricha (1. Ceratiomyxa fruticulosa (Miill. Macbr., Physarum stellatum (Mass. Mart., Stemonitis pallida Win. e Comatricha typhoides (Bull. Rost. são referidas pela primeira vez para este tipo de substrato. Este trabalho eleva para 35 o número de espécies de Myxomycetes assinaladas sobre palmeiras até o momento.Palm trees are specialized ecossystems which hosts a wide variety of organisms, including Myxomycetes. This paper reports twelve species of Myxomycetes found on dead leaves, spathes and stipitis of Acrocomia intumescens Drude, Copernicea prunifera (Mill. H. E. Moore, Mauritia flexuosa Mart., and Orbygnia phalerata Mart. The collecting area is located in the Municipality Crato of Ceará State, Northeastern Brazil (7º 30'00" S, 39º 00' 00" W, 400-1200 m altitude. Samples were taken at random and Myxomycetes fructifications were searched on dead and living organs of palm trees. Exsiccatae have been deposited in the Herbarium UFP (Department of Botany, Federal University of Pernambuco, Recife-PE, Brazil. The species registered belong to the

The opossum Didelphis virginiana as a synanthropic reservoir of Trypanosoma cruzi in Dzidzilché, Yucatán, México

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Ruiz-Piña, Hugo A; Cruz-Reyes, Alejandro

2002-01-01

In México, the role of mammals in the transmission cycle of Trypanosoma cruzi is poorly known. In the State of Yucatán, an endemic area of Chagas disease, both Didelphis virginiana and D. marsupialis occur sympatrically. However, until now, only the former species had been found infected with T. cruzi. To evaluate the role of D. virginiana in a peridomestic transmission, nine periods of capture-recapture were performed around the village of Dzidzilché, Yucatán. The sex, age, reproductive stat...

Agronomic, morphogenic and structural characteristics of Marandu grass in silvopastoral systems composed of babassu palm and grass monoculture

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Rosane Cláudia Rodrigues

2016-09-01

Full Text Available This study evaluated the agronomic, morphogenic and structural characteristics of palisadegrass (Urochloa brizantha in silvopastoral systems (SSP’s composed of babassu palms (Attalea speciosa and grass monoculture in the Pre-Amazon region of the state of Maranhão, Brazil. The study followed a completely randomized design, with the arrangement in split plots with six replicates for the evaluation of agronomic characteristics and 30 repetitions for the morphogenic and structural characteristics. The plots were divided into pasture environments with different palm densities (monoculture, 80, 131, 160 palms.ha-¹, and the subplots were divided into the different seasons (rainy and dry. Total forage production was affected (P 0.05 by pastoral system during the rainy season, but in the dry period, higher responses were obtained in SSPs. Overall, SSPs with 80 palms.ha-¹ favored the agronomic characteristics of pastures. Morphogenic and structural characteristics were favored by increasing palm densities. Leaf senescence and duration were not affected by the system.

Wild species of interest for tourism in Manabí and Guayas, Ecuador

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Sonia Rosete Blandariz

2018-01-01

Full Text Available Ethnobotany is the discipline that studies the relationships between man and plants. The purpose of the study was to identify the uses of wild species of interest for tourism in Manabí and Guayas. Interviews, walks and field observations were carried out in areas with little disturbed vegetation. Seventeen species were reported with at least one recognized use, some used for the manufacture of artisanal, ornamental objects, and the majority in danger of extinction due to the degradation of their habitat. The species of greatest interest for tourism due to their beauty and degree of scarcity are Attalea colenda (O.F.Cook Balslev & A.J.Hend. (Arecaceae, Brassia jipijapensis Dodson & N.H.Williams (Orchidaceae, Ceiba trischistandra (A. Gray Bakhuisen (Malvaceae, Erythrina megistophylla Diels (Fabaceae, Erythrina smithiana Krukoff Fabaceae, Macroclinium manabinum (Dodson Dodson (Orchidaceae, Passiflora sprucei Mast. (Passifloraceae, Phytelephas aequatorialis Spruce (Arecaceae and Prestoea acuminata (Willd. H.E.Moore var. acuminata (Arecaceae.

USOS DE LAS PALMAS EN LAS TIERRAS BAJAS DEL PACÍFICO COLOMBIANO

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EVA DOLORES LEDEZMA-RENTERÍA

2014-06-01

Full Text Available Con el fin de evaluar el conocimiento sobre usos de las palmas en el Pacífico colombiano, para orientar las investigaciones futuras y para definir patrones generales de uso en la región, estudiamos las fuentes de información que documentan usos en esta región. Se registraron 90 tipos de usos en 52 especies de palmas útiles en el Pacífico, que equivalen al 61 % de las palmas que crecen en la región. Los usos se agruparon en ocho categorías de uso y 30 subcategorías; las categorías de uso más importantes fueron construcción, utensilios y herramientas, y alimentación humana. Las especies que registraron mayor número de usos fueron Bactris gasipaes, Astrocaryum standleyanum, Oenocarpus bataua, Euterpe oleracea, Oenocarpus minor, Cocos nucifera, Attalea cuatrecasana, Iriartea deltoidea, Desmoncus cirrhifer y Wettinia quinaria.

Effect of Carapa guianensis Aublet (Andiroba and Orbignya phalerata (Babassu in colonic healing in rats

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Cícero Evandro Soares Silva

Full Text Available Objective: to evaluate the healing effect of the babassu aqueous extract and andiroba oil on open wounds in the cecum of rats. Methods: fifty-four Wistar rats were divided into three groups of 18: 1 babassu group with application of aqueous extract of babassu; 2 andiroba group with application of the oil; and 3 control group, with application of saline solution. All procedures were done by gavage. Each group was divided into three subgroups of six animals according to the observation period of 7, 14 or 21 days. From each animal was removed caecum fragment of 1.5cm² diameter. The areas of the lesions were analyzed macroscopically and resected specimens by light microscopy using hematoxylin-eosin and Masson's trichrome. Results: abscess and infection were observed in two aroeira group animals, and in one only hematoma. In relationship to adhesions degree, babassu group had higher incidence of grade II while in the control and aroeira groups predominated adhesions grade I. On microscopic examination on day 7 fibroblast proliferation was greater in aroeira and lower in babassu group (p=0.028. On the 14th day polymorphonuclear were less pronounced in babassu (p=0.007. As for the resistance test of air insufflation, it was observed that in all andiroba group in all tested days showed be higher. As for collagen, on the 7th day it was present in 100% of animals of aroeira group. On the 14th day was more pronounced in the control group and at day 21 similar results were found in the control and aroeira groups. Conclusion: animals in babassu and andiroba groups showed better cecum healing compared to the control group.

Shedding of a low pathogenic avian influenza virus in a common synanthropic mammal--the cottontail rabbit.

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J Jeffrey Root

Full Text Available BACKGROUND: Cottontails (Sylvilagus spp. are common mammals throughout much of the U.S. and are often found in peridomestic settings, potentially interacting with livestock and poultry operations. If these animals are susceptible to avian influenza virus (AIV infections and shed the virus in sufficient quantities they may pose a risk for movement of avian influenza viruses between wildlife and domestic animals in certain situations. METHODOLOGY/PRINCIPAL FINDINGS: To assess the viral shedding potential of AIV in cottontails, we nasally inoculated fourteen cottontails with a low pathogenic AIV (H4N6. All inoculated cottontails shed relatively large quantities of viral RNA both nasally (≤ 10(6.94 PCR EID50 equivalents/mL and orally (≤ 10(5.09 PCR EID50 equivalents/mL. However, oral shedding tended to decline more quickly than did nasal shedding. No animals showed any obvious signs of disease throughout the study. Evidence of a serological response was found in all infected rabbits at 22 days post infection in convalescent sera. CONCLUSIONS/SIGNIFICANCE: To our knowledge, cottontails have not been previously assessed for AIV shedding. However, it was obvious that they shed AIV RNA extensively via the nasal and oral routes. This is significant, as cottontails are widely distributed throughout the U.S. and elsewhere. These mammals are often found in highly peridomestic situations, such as farms, parks, and suburban neighborhoods, often becoming habituated to human activities. Thus, if infected these mammals could easily transport AIVs short distances.

Sanitary quality of the rivers in the Communities of Manguinhos´ Territory, Rio de Janeiro, RJ

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Natasha Berendonk Handam

2018-02-01

Full Text Available Sanitation actions are rare in the communities of Manguinhos, so evaluation of the sanitary conditions of the river waters and the peridomestic soils of the communities allows the diagnosis of the risk of contamination. This study evaluated coliform levels (total coliforms and Escherichia coli by the filter membrane method, and parasitological (by adapted Lutz and Baermann-Moraes methods in the waters and soils of the Faria-Timbó, Jacaré and Canal do Cunha Rivers that pass through the communities of the Territory of Manguinhos, RJ, according to the standards established in Brazilian legislation. In all points of the rivers, the water was unfit, with an average level of Escherichia coli 3,800 times higher than that standardized in CONAMA Resolution No. 274/2000. Larvae, helminths eggs and protozoan oocysts were observed. Soil samples were also unfit, with mean total coliform level 77,000 times higher than that considered acceptable by SMAC Resolution 468/2010. The Escherichia coli average level was 53,000 times higher than that permitted by the legislation. However, helminths eggs were found in only one soil sample. It was concluded that the lack of sanitation in this locality results in the high coliform and parasitological levels of the river waters and in the peridomestic soils, and that immediate modifications are needed to the Brazilian environmental paradigm, which uses its water bodies as sewage disposal ditches.

Chagas Disease Vector Control in Tupiza, Southern Bolivia

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G Guillen

1997-01-01

Full Text Available Heavy domestic and peridomestic infestations of Triatoma infestans were controlled in two villages in southern Bolivia by the application of deltamethrin SC25 (2.5% suspension concentrate at a target dose of 25 mg a.i./m². Actual applied dose was monitored by HPLC analysis of filter papers placed at various heights on the house walls, and was shown to range from 0 to 59.6 about a mean of 28.5 mg a.i./m². Wall bioassays showed high mortality of T. infestans during the first month after the application of deltamethrin. Mortality declined to zero as summer temperatures increased, but reappeared with the onset of the following winter. In contrast, knockdown was apparent throughout the trial, showing no discernible temperature dependence. House infestation rates, measured by manual sampling and use of paper sheets to collect bug faeces, declined from 79% at the beginning of the trial to zero at the 6 month evaluation. All but one of the houses were still free of T. infestans at the final evaluation 12 months after spraying, although a small number of bugs were found at this time in 5 of 355 peridomestic dependencies. Comparative cost studies endorse the recommendation of large-scale application of deltamethrin, or pyrethroid of similar cost-effectiveness, as a means to eliminate domestic T. infestans populations in order to interrupt transmission of Chagas disease

The rising importance of Triatoma rubrofasciata

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Jean-Pierre Dujardin

2015-05-01

Full Text Available The migration of invasive vector species has contributed to the worldwide extension of infectious diseases such as dengue (Aedes aegypti and chikungunya (Aedes albopictus. It is probably a similar behaviour for certain vectors of Chagas disease which allowed it to become a continental burden in Latin America. One of them, Triatoma rubrofasciata has also been spreading throughout the tropical and subtropical world. Here, the recent and massive peridomestic presence of T. rubrofasciata in Vietnam cities is reported, and tentatively explained, highlighting the need for improved entomological surveillance.

Presence of Lutzomyia longipalpis (Diptera: Psychodidae) in the Parque Estadual da Serra da Tiririca, State of Rio de Janeiro, Southeastern Brazil.

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Fuzari, Andressa Alencastre; Delmondes, Aline Ferreira Dos Santos; Barbosa, Vanessa De Araújo; Marra, Francisco de Assis; Brazil, Reginaldo Peçanha

2016-01-01

The sand fly, Lutzomyia longipalpis, is the main vector of Leishmania infantum in the Americas, primarily occurring in areas of apparent anthropomorphic modifications in several regions of Brazil. Sand flies were captured using light traps. Out of all captured species, Lu. longipalpis numbers had increased within the park. We report the occurrence of Lu. longipalpis in an area of Atlantic Forest, possibly representing the first sylvatic population of Lu. longipalpis in an area absent of peridomestic captures, but with the risk of L. infantum transmission in the areas of Niterói and Maricá.

Distribution of triatomine species in domestic and peridomestic environments in central coastal Ecuador

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Villacís, Anita G.; Moncayo, Ana L.; Ocaña-Mayorga, Sofia; Yumiseva, Cesar A.; Baus, Esteban G.

2017-01-01

Background Although the central coast of the Ecuador is considered endemic for Chagas disease, few studies have focused on determining the risk of transmission in this region. In this study we describe the triatomine household infestation in Manabí province (Central Coast region), determine the rate of Trypanosoma cruzi infection and study the risk factors associated with infestation by Rhodnius ecuadoriensis. Methodology/Principal findings An entomological survey found three triatomine species (Rhodnius ecuadoriensis, Panstrongylus rufotuberculatus and P. howardi) infesting domiciles in 47.4% of the 78 communities visited (total infestation rate of 4.5%). Four percent of domiciles were infested, and nymphs were observed in 77% of those domiciles. The three species were found in altitudes below 500 masl and in all ecological zones except cloud forest. Within the domicile, we found the three species mostly in bedrooms. Rhodnius ecuadoriensis and P. rufotuberculatus were abundant in bird nests, including chicken coops and P. howardi associated with rats in piles of bricks, in the peridomicile. Triatomine infestation was characterized by high rates of colonization, especially in peridomicile. Flagelates infection was detected in only 12% of the samples by microscopy and Trypanosoma cruzi infection in 42% of the examined triatomines by PCR (n = 372). The most important risk factors for house infestation by R. ecuadoriensis were ecological zone (w = 0.99) and presence of chickens (w = 0.96). Determinants of secondary importance were reporting no insecticide applications over the last twelve months (w = 0.86) and dirt floor (w = 0.70). On the other hand, wood as wall material was a protective factor (w = 0.85). Conclusion/Significance According the results, approximately 571,000 people would be at high risk for T. cruzi infection in Manabí province. A multidisciplinary approximation and the adhesion to a periodic integrated vector management (IVM) program are essential to guarantee sustainable preventive and control strategies for Chagas disease in this region. PMID:28968383

Distribution of triatomine species in domestic and peridomestic environments in central coastal Ecuador.

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Mario J Grijalva

2017-10-01

Full Text Available Although the central coast of the Ecuador is considered endemic for Chagas disease, few studies have focused on determining the risk of transmission in this region. In this study we describe the triatomine household infestation in Manabí province (Central Coast region, determine the rate of Trypanosoma cruzi infection and study the risk factors associated with infestation by Rhodnius ecuadoriensis.An entomological survey found three triatomine species (Rhodnius ecuadoriensis, Panstrongylus rufotuberculatus and P. howardi infesting domiciles in 47.4% of the 78 communities visited (total infestation rate of 4.5%. Four percent of domiciles were infested, and nymphs were observed in 77% of those domiciles. The three species were found in altitudes below 500 masl and in all ecological zones except cloud forest. Within the domicile, we found the three species mostly in bedrooms. Rhodnius ecuadoriensis and P. rufotuberculatus were abundant in bird nests, including chicken coops and P. howardi associated with rats in piles of bricks, in the peridomicile. Triatomine infestation was characterized by high rates of colonization, especially in peridomicile. Flagelates infection was detected in only 12% of the samples by microscopy and Trypanosoma cruzi infection in 42% of the examined triatomines by PCR (n = 372. The most important risk factors for house infestation by R. ecuadoriensis were ecological zone (w = 0.99 and presence of chickens (w = 0.96. Determinants of secondary importance were reporting no insecticide applications over the last twelve months (w = 0.86 and dirt floor (w = 0.70. On the other hand, wood as wall material was a protective factor (w = 0.85.According the results, approximately 571,000 people would be at high risk for T. cruzi infection in Manabí province. A multidisciplinary approximation and the adhesion to a periodic integrated vector management (IVM program are essential to guarantee sustainable preventive and control strategies for Chagas disease in this region.

Differential application of lambda-cyhalothrin to control the sandfly Lutzomyia longipalpis.

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Kelly, D W; Mustafa, Z; Dye, C

1997-01-01

To study the impact of residual pyrethroid insecticide on the abundance and distribution of peridomestic Lutzomyia longipalpis, the sandfly vector of visceral leishmaniasis in Brazil, lambda-cyhalothrin was applied at 20 mg a.i.m-2 in the following interventions: (i) spraying of all animal pens in a village (blanket coverage); (ii) treatment of a subset of animal pens, either by spraying, or by installation of insecticide-impregnated 1 m2 cotton sheets as 'targets' (focal coverage). By sampling with CDC light traps, and using a novel analytical approach, we detected a 90% reduction in Lu.longipalpis abundance in sprayed sheds of the focal intervention. However, there was no discernible effect on the abundance of other phlebotomines trapped in sheds, or on the abundance of Lu.longipalpis in untreated dining-huts and houses. This differential impact on Lu.longipalpis abundance is explained in terms of the disruption of male pheromone production. Treated targets were approximately half as effective as residual spraying in reducing the abundance of Lu.longipalpis in sheds. Following blanket intervention, the abundance of Lu.longipalpis in traps fell by only 45% (not significant): catches at untreated dining-huts actually increased, possibly because the blanket coverage diverted Lu.longipalpis away from major aggregation sites at animal pens. It is recommended that care be taken during vector control programmes to ensure that all potential aggregation sites are treated. The possible consequences of leaving some sites untreated include poor control of peridomestic sandfly abundance and an increase in the biting rate on dogs and humans.

Extended viral shedding of a low pathogenic avian influenza virus by striped skunks (Mephitis mephitis.

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J Jeffrey Root

Full Text Available BACKGROUND: Striped skunks (Mephitis mephitis are susceptible to infection with some influenza A viruses. However, the viral shedding capability of this peri-domestic mammal and its potential role in influenza A virus ecology are largely undetermined. METHODOLOGY/PRINCIPAL FINDINGS: Striped skunks were experimentally infected with a low pathogenic (LP H4N6 avian influenza virus (AIV and monitored for 20 days post infection (DPI. All of the skunks exposed to H4N6 AIV shed large quantities of viral RNA, as detected by real-time RT-PCR and confirmed for live virus with virus isolation, from nasal washes and oral swabs (maximum ≤ 10(6.02 PCR EID50 equivalent/mL and ≤ 10(5.19 PCR EID50 equivalent/mL, respectively. Some evidence of potential fecal shedding was also noted. Following necropsy on 20 DPI, viral RNA was detected in the nasal turbinates of one individual. All treatment animals yielded evidence of a serological response by 20 DPI. CONCLUSIONS/SIGNIFICANCE: These results indicate that striped skunks have the potential to shed large quantities of viral RNA through the oral and nasal routes following exposure to a LP AIV. Considering the peri-domestic nature of these animals, along with the duration of shedding observed in this species, their presence on poultry and waterfowl operations could influence influenza A virus epidemiology. For example, this species could introduce a virus to a naive poultry flock or act as a trafficking mechanism of AIV to and from an infected poultry flock to naive flocks or wild bird populations.

Influence of electron beam Irradiation on PP/Piassava fiber composite prepared by melt extrusion process

International Nuclear Information System (INIS)

Gomes, Michelle G.; Ferreira, Maiara S.; Oliveira, Rene R.; Silva, Valquiria A.; Teixeira, Jaciele G.; Moura, Esperidiana A.B.

2013-01-01

In the latest years, the interest for the use of natural fibers in materials composites polymeric has increased significantly due to their environmental and technological advantages. Piassava fibers (Attalea funifera) have been used as reinforcement in the matrix of thermoplastic and thermoset polymers. In the present work (20%, in mass), piassava fibers with particle sizes equal or smaller than 250 μm were incorporated in the polypropylene matrix (PP) no irradiated and polypropylene matrix containing 10 % and 30 % of polypropylene treated by electron-beam radiation at 40 kGy (PP/PPi/Piassava). The composites PP/Piassava and PP/PPi/Piassava were prepared by using a twin screw extruder, followed by injection molding. The composite material samples obtained were treated by electron-beam radiation at 40 kGy, using a 1.5 MeV electron beam accelerator, at room temperature, in presence of air. After irradiation treatment, the irradiated and non-irradiated specimens tests samples were submitted to thermo-mechanical tests, melt flow index (MFI), sol-gel analysis, X-Ray diffraction (XRD) and scanning electron microscopy (SEM). (author)

Combination of peracetic acid and ultrasound reduces Salmonella Typhimurium on fresh lettuce (Lactuca sativa L. var. crispa).

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Silveira, Luiza Oliveira; do Rosário, Denes Kaic Alves; Giori, Ana Carolina Garcia; Oliveira, Syllas Borburema Silva; da Silva Mutz, Yhan; Marques, Clara Suprani; Coelho, Jussara Moreira; Bernardes, Patrícia Campos

2018-04-01

Salmonella outbreaks related to fruits and vegetables have been reported being lettuce one of the most contaminated. Peracetic acid (PA) at 50 mg/L, sodium dichloroisocyanurate (SD) at 100 mg/L, and the combination of SD at 100 mg/L and babaçu coconut ( Attalea speciosa ) oil detergent at 100 mg/L were applied to fresh lettuce. Natural contaminant microbiota, physicochemical characteristics, and sensory attributes were evaluated. PA and SD reduced mesophilic aerobic counts by 2.1 and 1.5 log cfu/g, respectively. The most efficient treatment in reducing natural microbiota (i.e., PA) was applied alone and in combination with ultrasound (US). It reduced Salmonella enterica Typhimurium counts to undetectable levels (< 1 log cfu/g). US further reduced S. Typhimurium counts by 0.6 log cfu/g in relation to PA, treatment which lessened the pH but increased the titratable acidity of lettuce, but did not cause total color difference. Therefore, the combination of PA and US holds a potential industrial application for sanitization purposes.

Environmental variables, remote sensing and geographical information systems applied to the study of Rhodnius prolixus distribution in Colombia

International Nuclear Information System (INIS)

Guhl, Felipe

2010-01-01

A data base of the entomological survey performer during the Chagas Disease National Control Programme (CHDNCP) in 1997 - 2001 and temporal satellite images masp containing 57 environmental variables were used to build Rhodnius prolixus dispersion predictive maps in Colombia, based on temporal images, Fourier analyses and a discriminative multivaried statistical analyses of the variables studied. The maps show the dispersion of this species and its implication on the Chagas disease transmission in Colombia. A clear division in the predictive dispersion of R. prolixus in two geographical zones was found: one area in the southeast of the Eastern Cordillera associated with the environmental variables used in the present study and a second zone in the Andean Valleys, East of the Eastern Cordillera not much defined by the same variables. This would suggest that the Southwest Region. of Colombia presents a tendency to a wider dispersion of R. prolixus associated to other variables like human intervention. Sylvatic populations of R. prolixus were found recently in Attalea butyracea palm trees in this Region of the Eastern Planes demonstrating the prediction of the presence of this species.

Throughfall and temporal trends of rainfall redistribution in an open tropical rainforest, south-western Amazonia (Rondônia, Brazil

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S. Germer

2006-01-01

Full Text Available Throughfall volumes and incident rainfall were measured between 23 August and 2 December 2004 as well as from 6 January to 15 April 2005 for individual rain events of differing intensities and magnitudes in an open tropical rainforest in Rondônia, Brazil. Temporal patterns of throughfall spatial variability were examined. Estimated interception was compared to modeled interception obtained by applying the revised Gash model in order to identify sources of throughfall variability in open tropical rainforests. Gross precipitation of 97 events amounted to 1309 mm, 89±5.6% (S.E. of which reached the forest floor as throughfall. The redistribution of water within the canopy was highly variable in time, which we attribute to the high density of babassu palms (Orbignya phalerata, their seasonal leaf growth, and their conducive morphology. We identified a 10-min rainfall intensity threshold of 30 mmh-1 above which interception was highly variable. This variability is amplified by funneling and shading effects of palms. This interaction between a rainfall variable and vegetation characteristics is relevant for understanding the hydrology of all tropical rainforests with a high palm density.

Proteins of Bacuri almonds: nutritional value and in vivo digestibility

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Magalli Costa Barbosa Lima e Silva

2014-03-01

Full Text Available Bacuri (Scheelea phalerata Mart. is a type of palm fruit tree widely distributed in the Brazilian Cerrado. The objective of this paper was to study the almonds of bacuri, in their form in natura and processed, focusing on their nutritional value through the profile of amino acids, anti-nutritional factors and in vivo digestibility. Raw and toasted samples of the almond presented a high level of proteins and fiber. Proteins of raw bacuri almond showed no limiting amino acid when compared to the ones recommended by FAO/WHO, and histidine was the most limiting essential amino acid in the toasted almonds. The almond of bacuri does not present anti- nutritional factors. In an assay with rats fed with control (casein, tests (bacuri almond flours and aproteic diets, we verified the quantity of ration ingested and body weight gain, determining the urinary and metabolic nitrogen. Rats treated with the test diets presented inferior values of True Digestibility (DV, (82.9 and 72.3%, respectively for the raw and toasted almonds when compared to the control group (92.3%. The raw bacuri almond presented a superior nutritional value to the one found in the toasted almond.

Meta-analysis to estimate the load of Leptospira excreted in urine: beyond rats as important sources of transmission in low-income rural communities.

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Barragan, Veronica; Nieto, Nathan; Keim, Paul; Pearson, Talima

2017-01-28

Leptospirosis is a major zoonotic disease with widespread distribution and a large impact on human health. Carrier animals excrete pathogenic Leptospira primarily in their urine. Infection occurs when the pathogen enters a host through mucosa or small skin abrasions. Humans and other animals are exposed to the pathogen by direct contact with urine, contaminated soil or water. While many factors influence environmental cycling and the transmission of Leptospira to humans, the load of pathogenic Leptospira in the environment is likely to play a major role. Peridomestic rats are often implicated as a potential source of human disease; however exposure to other animals is a risk factor as well. The aim of this report is to highlight the importance of various carrier animals in terms of the quantity of Leptospira shed into the environment. For this, we performed a systematic literature review and a meta-analysis of the amount of pathogen that various animal species shed in their urine. The quantity of pathogen has been reported for cows, deer, dogs, humans, mice, and rats, in a total of 14 research articles. We estimated the average Leptospira per unit volume shed by each animal species, and the daily environmental contribution by considering the total volume of urine excreted by each carrier animal. Rats excrete the highest quantity of Leptospira per millilitre of urine (median = 5.7 × 10 6  cells), but large mammals excrete much more urine and thus shed significantly more Leptospira per day (5.1 × 10 8 to 1.3 × 10 9  cells). Here we illustrate how, in a low-income rural Ecuadorian community, host population demographics, and prevalence of Leptospira infection can be integrated with estimates of shed Leptospira to suggest that peridomestic cattle may be more important than rats in environmental cycling and ultimately, transmission to humans.

Environmental management for the control of Triatoma dimidiata (Latreille, 1811, (Hemiptera: Reduviidae in Costa Rica: a pilot project

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Rodrigo Zeledón

2006-06-01

Full Text Available An ecological control method, using environmental management operations, based on biological and behavioral characteristics of Triatoma dimidiata (Latreille, 1811, was implemented as a pilot project in an area of Costa Rica where the bug is prevalent. The sample was represented by 20 houses with peridomestic colonies (two also had indoor infestation, divided in two equivalent groups of 10 each. In one group we intervened the houses, i.e. all objects or materials that were serving as artificial ecotopes for the bugs were removed, and the second group was used as control houses. After a year of periodic follow up, it became evident that in those houses with a modified environment the number of insects had decreased notoriously even after the first visits and this was more evident after a period of 12.5 to 13.5 months in which no insects were detected in eight of the houses. It also became clear that in this group of houses, recolonization by wild bugs from the surrounding areas, became more difficult, probably due to the absence of protection from bug predators. In the control houses, with the exception of three in which the inhabitants decided to intervene on their own, and another house with a peculiar situation, the insect populations remained the same or even showed a tendency to increase, as confirmed at the end of the experiment. We believe that the method is feasible, low costing and non contaminating. It could be used successfully in other places where T. dimidiata is common and also in countries where other species colonize peridomestic areas of homes. Environmental management of this kind should seek the participation of the members of the communities, in order to make it a more permanent control measure.

La modificacion del biotopo perihabitacional en la profilaxis de la enfermedad de Chagas

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Miguel Eduardo Jörg

1989-06-01

Full Text Available La modification del biotopo perihabitacional consiste en crear alrededor de la vivienda humana, rural, selvática o suburbuna, un espado perimetral limpio, totalmente libre de malezas y chaparral, despojado de nidos, madrigueras o refúgios de animales silvestres y de habitáculos de animales domésticos; de suficiente magnitud para evitar que tras desinsectación, queden focos peridomiciliarios de proliferation de triatomineos, vectores del Trypanosoma cruzi, focos inmediatos y habituales de reinfestación domiciliaria por estos redúvidos hematófagos. Los trabajos de rociado entomicida y aún el mejoramiento de la vivienda se reducen extremadamente si no son complementadas con la modificación del biotopo perihabitacional. Se expone una experiencia piloto sobre un barrio de la ciudad Villa Carlos Paz, provinda Córdoba, Argentina, que en 2 anos de aplicación permitió verificar la desaparición de vinchucas en un area de baja desindad de vectores y hospedadores.In zones endemic for the American trypanosomiasis the modification of the biotopes surrounding human, rural, sylvatic or suburban housing, involves the arrangement of a clean perimetral area completely free of shrubs and chaparral, devoid of dens of wild animals and dwellings of domestic animals, to hinder the persistence of peridomestic foci where the proliferation of Triatomine bugs encourage the reinfestation of the human lodgings. The success of insecticide spraying campaigns, even with simultaneous amelioration of housing, are enhanced by tne modification of the biotopes. A pilot field experience is presented; a 2 year active campaign in a suburban area of Villa Carlos Paz, province Cordoba, Argentina, confirming the methods to eliminate reinfestation of houses from peridomestic sites, in an area of low vector density.

Diversity patterns, Leishmania DNA detection, and bloodmeal identification of Phlebotominae sand flies in villages in northern Colombia.

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González, Camila; León, Cielo; Paz, Andrea; López, Marla; Molina, Gisell; Toro, Diana; Ortiz, Mario; Cordovez, Juan Manuel; Atencia, María Claudia; Aguilera, Germán; Tovar, Catalina

2018-01-01

Leishmaniases are neglected tropical diseases exhibiting complex transmission cycles due to the number of parasite species circulating, sand fly species acting as vectors and infected mammals, including humans, which are defined in the New World as accidental hosts. However, current transmission scenarios are changing, and the disease is no longer exclusively related to forested areas but urban transmission foci occur, involving some species of domestic animals as suspected reservoirs. The aim of this study was to determine the transmission cycles in urban environments by evaluating sand fly diversity, detection of Leishmania DNA, and bloodmeal sources through intra and peridomestic collections. The study was carried out in Colombia, in 13 municipalities of Cordoba department, implementing a methodology that could be further used for the evaluation of vector-borne diseases in villages or towns. Our sampling design included 24 houses randomly selected in each of 15 villages distributed in 13 municipalities, which were sampled in two seasons in 2015 and 2016. Sand flies were collected using CDC light traps placed in intra and peridomestic habitats. In addition to the morphological identification, molecular identification through DNA barcodes was also performed. A total of 19,743 sand flies were collected and 13,848 of them (10,268 females and 3,580 males) were used in molecular procedures. Circulation of two known parasite species-Leishmania infantum and Leishmania panamensis was confirmed. Blood source analyses showed that sand flies fed on humans, particularly in the case of the known L. infantum vector, P. evansi; further analyses are advised to evaluate the reservoirs involved in parasite transmission. Our sampling design allowed us to evaluate potential transmission cycles on a department scale, by defining suspected vector species, parasite species present in different municipalities and feeding habits.

Rickettsia felis in fleas from Catalonia (Northeast Spain).

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Nogueras, María-Mercedes; Pons, Immaculada; Ortuño, Anna; Lario, Sergio; Segura, Ferran

2011-05-01

Rickettsia felis produces a syndrome indistinguishable from murine typhus, which has been described in Spain. R. felis is transmitted to humans by fleas. Although no clinical case has been described so far, serologic evidence of infections in humans, cats, and dogs has been obtained in our area. However, no study has been conducted regarding its presence in vectors. Recognition of routes of transmission is of great importance to prevent infection in humans. Taking into account these results, R. felis seems to be present in animals that are in contact with humans. The aim of this study was to determine the presence of R. felis in the fleas of cats and dogs from Northeast Spain, to show the presence of peridomestic cycle in our area. Between May 2006 and July 2008, 78 fleas were collected. Sixty-three fleas were recovered from kennels. Most of them were collected from cages and a few of them on dogs and cats living in kennels. Fifteen fleas were collected from dogs and cats attended at a veterinary clinic. Fleas were rinsed with ethanol, dried, identified, and stored at 4°C. DNA was extracted from each flea individually. Rickettsial DNA was determined by quantitative real-time polymerase chain reaction. OmpB-specific primers and molecular beacon probes targeting specifically R. felis were used. All 78 fleas were identified as Ctenocephalides felis. R. felis was detected in 34 (43.6%) fleas. No nucleic acids were amplified from negative controls and expected results were obtained from positive controls. Eight positive samples were also confirmed by sequencing. R. felis was found in a high percentage of Ct. felis from cats and dogs. It seems that there is a peridomestic cycle in Northeast Spain, which would allow contact of R. felis with humans.

Ecological aspects of Rhodnius nasutus Stål, 1859 (Hemiptera: Reduviidae: Triatominae in palms of the Chapada do Araripe in Ceará, Brazil

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Fernando Braga Stehling Dias

2008-12-01

Full Text Available The aim of this work is to present aspects related to the ecology of Rhodnius nasutus Stål, 1859 in palms from Chapada do Araripe in Ceará, Brazil. The following five species of palms were investigated: babaçu (Attalea speciosa, buriti (Mauritia flexuosa, carnaúba (Copernicia prunifera, catolé (Syagrus oleracea and macaúba-barriguda (Acrocomia intumescens. Fifth palms were dissected (10 specimens for each species. The overall infestation index was 86%, with a total of 521 triatomines collected. The Trypanosoma cruzi Chagas, 1909 Index was 16.8% and two insects presented mixed infection with Trypanosoma rangeli Tejera, 1920. A precipitin test showed that R. nasutus from palms of Chapada do Araripe are associated with opossum and bird although other possible bloodmeals were observed. Our results showing a high index of infestation of the palms as well as T. cruzi infection, the association of R. nasutus with the most diverse species of palms and proximity of these palms to houses demonstrate the importance of this area for sylvatic T. cruzi transmission and suggest the need for epidemiological surveillance in the region of the Chapada do Araripe.

Analysis of the mechanical resistance and porosity of a composite cement with EVA and reinforced with piacava fibers; Analise da resistencia mecanica e porosidade de um composito cimenticio leve com EVA e reforcado com fibras de piacava

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Silva, R.M.; Dominguez, D.S.; Alvim, R.C.; Iglesias, S.M., E-mail: regilan@hotmail.com [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil)

2013-07-01

Nowadays, a lot of solid waste material is discarded into the environment. One of these residues is the EVA (Ethyl Vinyl Acetate) which has the footwear industry, as its main consumer. Studies are focused on the reusing of these materials, particularly in the civil construction, where is used as an aggregate in the production of light mortars. Due to the specific characteristics of lightweight concrete, is necessary to reinforce these materials. The palm Attalea Funifera Martius, known as piacava, may be an excellent alternative as a reinforcement element in light cement mixes. In this work, it's verified the mechanical strength of a composite lightweight cementitious with EVA and reinforced with Piacava fibers, also, the porosity of the new material was measured. To evaluate the mechanical properties of this new material was made mechanical tests and verified the importance of vegetal fibers as the material reinforcing. For the compound porosity evaluation, samples were studied using microcomputer tomography (μTC). With images processing techniques we identify and quantify the pores. The processing digital images through μTC showed up as a non-destructive method for efficient and acceptable results. (author)

Investigación de vectores y reservorios en brote de Chagas agudo por posible transmisión oral en Aguachica, Cesar, Colombia

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Hugo Soto

2014-04-01

Full Text Available Colombia tiene un registro de 11 casos de Chagas agudo y 80 casos por contaminación oral con Trypanosoma cruzi. Este trabajo analiza los hallazgos entomológicos y parasitológicos del brote de Aguachica, Cesar, en 2010. Un grupo interdisciplinario de profesionales de la salud y de universidades regionales realizó las pruebas de laboratorio a los pacientes y el estudio del foco de transmisión. Se detectaron 11 casos agudos de enfermedad de Chagas en una sola familia con vivienda sin triatominos domiciliados y, Rhodnius pallescens, Pantrongylus geniculatus, Eratyrus cuspidatus y dos Didelphis marsupialis infectados con T. cruzi en palmas de Attalea butyracea y Elaeis oleifera del área urbana de Aguachica. Se analiza la participación del R. pallescens y el rol de las palmas en el ciclo silvestre de T. cruzi y para la transmisión oral de la enfermedad de Chagas. Incursiones esporádicas de R. pallescens, P. geniculatus y E. cuspidatus silvestres desde palmas cercanas al domicilio humano pueden provocar brotes cada vez más frecuentes de Chagas oral.

Analysis of the mechanical resistance and porosity of a composite cement with EVA and reinforced with piacava fibers

International Nuclear Information System (INIS)

Silva, R.M.; Dominguez, D.S.; Alvim, R.C.; Iglesias, S.M.

2013-01-01

Nowadays, a lot of solid waste material is discarded into the environment. One of these residues is the EVA (Ethyl Vinyl Acetate) which has the footwear industry, as its main consumer. Studies are focused on the reusing of these materials, particularly in the civil construction, where is used as an aggregate in the production of light mortars. Due to the specific characteristics of lightweight concrete, is necessary to reinforce these materials. The palm Attalea Funifera Martius, known as piacava, may be an excellent alternative as a reinforcement element in light cement mixes. In this work, it's verified the mechanical strength of a composite lightweight cementitious with EVA and reinforced with Piacava fibers, also, the porosity of the new material was measured. To evaluate the mechanical properties of this new material was made mechanical tests and verified the importance of vegetal fibers as the material reinforcing. For the compound porosity evaluation, samples were studied using microcomputer tomography (μTC). With images processing techniques we identify and quantify the pores. The processing digital images through μTC showed up as a non-destructive method for efficient and acceptable results. (author)

Evaluation of acute toxicity of babassu mesocarp in mice

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Elizabeth S. B. Barroqueiro

2011-07-01

Full Text Available The safety of babassu mesocarp (Orbignya phalerata Mart., Arecaceae, which exhibited anti-inflammatory and antithrombotic activities, was evaluated by determining the potential acute toxicity in mice. A lyophilized ethanol extract of babassu mesocarp (BME was administered to C3H/HePas mice (10/group in a single dose of 1000, 3000 and 5000 mg/kg, by gavage. General behavior adverse effects and mortality were determined for up to fourteen days. Selected biochemical parameters including glucose, triacylglyceride, cholesterol, urea, alkaline phosphatase and creatinine were determined by colorimetric assay. The heart, liver, spleen, kidneys and brain were weighted and evaluated macro and microscopically. The median lethal dose (LD50 of BME was greater than 5000 mg/kg. No behavior or body weight alterations were detected after the treatment. The acute treatment with BME has no effect on macroscopic and microscopic aspect of examined organs. Instead, BME increased the alkaline phosphatase and reduced the urea concentration in all groups. A significant increase on triacylglyceride was detected in the group BME1000. In conclusion, the acute treatment with high doses of BME can affect some biochemical parameters with a long lasting effect, although any change was detected at tissue level or body and organ weight.

Botânica econômica, uma ciência importante para a região amazônica

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Ghillean T Prance

1988-01-01

Full Text Available A botânica econômica é uma ciência atualmente muito importante na região amazônica e deve ser adaptada às necessidades regionais. Neste trabalho, são fornecidos dados sobre o banco genético da floresta amazônica, espécies e dados econômicos da floresta de extração, sistemas agroflorestais, aproveitamento de monoculturas, naturais e cultivo das várzeas. É necessário um forte programa de botânica econômica para criar sistemas de uso racionais da floresta amazônica.The important contribution to be made by the science of Economic Botany in today's Amazonia environment is emphasized. Economy Botany must be tailored to the current situation where and uneccesary destruction is taking place. Studies are needed of the gene pool os useful plants and their wild relatives that occur in the forest; of products suitable for extraction from the forest; of agroforest, systems; os natural monospecific stands of such species as Orbignya phalerata and Mauritia flexuosa; and of plants suitable for cultivation on the várzea. The need for a strong programme in Amazonian Economic Bot any is stressed.

Tree species diversity in a seasonally-dry forest: the case of the Pinkaití site, in the Kayapó Indigenous Area, Southeastern limits of the Amazon Diversidade de espécies arbóreas em uma floresta sazonalmente seca: o caso da base de pesquisas do Pinkaití (PA, na Terra Indígena Kayapó, limite sudoeste da Amazônia

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Rodolfo Salm

2004-09-01

Full Text Available This study investigates patterns of forest structure and tree species diversity in an anthropogenic palm grove and undisturbed areas at the seasonally-dry Pinkaití research station, in the Kayapó Indigenous Area. This site, managed by the Conservation International do Brasil, is the most southeastern site floristically surveyed in the Amazon until now. The secondary and a nearby undisturbed forest were sampled in a group of 52 floristic plots of 0.0625-ha (25x25-m where all trees with DBH > 10 cm were measured and identified. The analyses were complemented with other two floristic plots of 1-ha (10x1000-m. The present study has shown that the Pinkaití, like other seasonally-dry forests, have great heterogeneity in forest structure and composition, associated with biotic characteristics of the most important tree species, natural disturbance and history of land-use. The palm grove, moderately dominated by the arborescent palm Attalea maripa (Aubl. Mart., presented high tree species diversity and was floristically similar to undisturbed forests at the study site. It is discussed the importance of large arborescent palms for the seasonally-dry Amazon forests regeneration.Este estudo compara a florística e estrutura e a diversidade de espécies arbóreas de um palmeiral antropogênico e áreas não perturbadas na floresta sazonalmente seca da base de pesquisas ecológicas do Pinkaití, na Terra Indígena Kayapó. Esta base de estudos, administrada pela Conservation International do Brasil, é a área mais ao sudoeste até o momento floristicamente amostrada na Amazônia. Uma mancha de floresta secundária e uma floresta não perturbada adjacente foram amostradas com um grupo de 52 parcelas de 0,0625-ha (25x25-m onde todas as árvores com DAP > 10 cm foram medidas e identificadas. As análises foram complementadas com outras duas parcelas de 1-ha (10x1000-m. Este estudo mostrou que o Pinkaití, como outras florestas sazonalmente secas, tem grande

Description of a newly discovered Triatoma infestans (Hemiptera: Reduviidae Foci in Ibipeba, State of Bahia, Brazil

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Renato Freitas Araújo

2014-07-01

Full Text Available Introduction Chagas disease transmitted by the Triatoma infestans was eradicated from Brazil in 2006. However, reports of triatomine foci threaten the control of Chagas disease. The goal of this study was to determine T. infestans foci in the City of Ibipeba, State of Bahia. Methods Triatominae specimens were collected in Ibipeba and entomologic indicators were calculated using indices of domiciliary infestation, density, and colonization. Results T. infestans foci was discovery in Ibipeba, State of Bahia. Approximately 95% of the specimens were discovered inside dwellings, of which 34% were T. infestans. This species was also discovered forming a colony in tree bark in the peridomicile. Conclusions Triatoma infestans foci in peridomestic ecotopes in Ibipeba, BA, indicate increased the risk of transmission Chagas disease.

Feeding and defaecation patterns in Triatoma sordida

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LB Crocco

1996-08-01

Full Text Available Triatoma sordida is a peridomestic Triatominae that could play an important role in the transmission of Trypanosoma cruzi, although its vectorial competence is not well known. The aim of this work was to evaluate two aspects of the vectorial competence: the feeding behaviour and defaecation patterns, and to compare them with T. infestans. The feeding and defaecation patterns were studied in adults and fifth instar nymphs of T. sordida fed ad libitum on a restrained pigeon. The results showed how the blood meal size controls excretion behaviour. Blood intake and time to first defaecation showed a significant negative correlation. Adults and nymphs frequently defaecated during the blood meal, reaching the maximum frequency within the first 10 minutes.

Propriedades da carne e perfil de ácidos graxos do pernil de catetos (Tayassu tajacu alimentados com torta de babaçu (Orbignya phalerata Meat properties and fatty acids profile of the ham of peccaries (Tayassu tajacu fed babassu (Orbignya phalerata meal

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N.I. Albuquerque

2009-12-01

Full Text Available Analisaram-se as propriedades da carne e o perfil de ácidos graxos do pernil de catetos alimentados com dietas contendo diferentes porcentagens de torta de babaçu, usada como fonte energética alternativa substituindo parte do milho na alimentação, em sistemas de produção em cativeiro. Avaliou-se o pernil de 12 animais quanto às suas propriedades - perda de peso ao cozimento, força de cisalhamento, pH e capacidade de retenção de água-, depois extraiu-se o óleo da carne e determinou-se o perfil dos ácidos graxos. Não foram observados efeitos (P>0,05 das porcentagens de torta de babaçu sobre as propriedades da carne; os ácidos graxos (AG insaturados, mono e poli-insaturados, foram encontrados em maior quantidade (51,6-57,8% que os ácidos graxos saturados (42,2-48,4% na carne do pernil. Baseando-se na teoria de que os AG poli-insaturados ingeridos na dieta humana são responsáveis pela redução nos níveis séricos de colesterol, sugere-se que a carne de catetos seja uma boa fonte alternativa de proteína.The meat properties and the fatty acids profile of the ham of peccaries ham fed diets with different levels of babassu meal, used as an alternative energy source substituting part of corn on feeding peccaries in captivity, were studied. The ham meats of 12 animals were evaluated on their properties: cooking losses, shear force, pH, and water holding capacity. After that, the meat oil was extracted to determine the fatty acids contents. No effects (P>0.05 of the babassu meal levels on the meat properties were observed. The unsaturated fatty acids, mono and polyunsaturated, were found in higher quantity than the saturated fatty acids in the ham meat of peccaries. Based on the theory that the polyunsaturated fatty acids ingested in the human diet are responsible for reduction of the seric levels of cholesterol, it can be suggested that the peccary meat is a good alternative source of protein.

Revisiting Amazonian Plants for Skin Care and Disease

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Bruno Burlando

2017-07-01

Full Text Available This review concerns five species of trees and palm trees that occur as dominant plants in different rainforest areas of the Amazon region. Due to their abundance, these species can be exploited as sustainable sources of botanical materials and include Carapa guianensis Aubl., family Meliaceae; Eperua falcata Aubl., family Fabaceae; Quassia amara L., family Simaroubaceae; and Attalea speciosa Mart. and Oenocarpus bataua Mart., family Arecaceae. For each species, the general features, major constituents, overall medicinal properties, detailed dermatological and skin care applications, and possible harmful effects have been considered. The major products include seed oils from A. speciosa and C. guianensis, fruit oil from O. bataua, and active compounds such as limonoids from C. guianensis, flavonoids from E. falcata, and quassinoids from Q. amara. The dermatologic and cosmetic applications of these plants are growing rapidly but are still widely based on empiric knowledge. Applications include skin rehydration and soothing; anti-inflammatory, antiage, and antiparasite effects; hair care; burn and wound healing; and the amelioration of rosacea and psoriasis conditions. Despite a limited knowledge about their constituents and properties, these species appear as promising sources of bioactive compounds for skin care and health applications. An improvement of knowledge about their properties will provide added value to the exploitation of these forest resources.

Chagas disease in an area of recent occupation in Cochabamba, Bolivia

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Albarracin-Veizaga Hugo

1999-01-01

Full Text Available INTRODUCTION: A descriptive, entomological and seroepidemiological study on Chagas disease was conducted in a place of recent occupation on the outskirts of Cochabamba, Bolivia: Avaroa/Primer de Mayo (population:3,000, where the socio-economic level is low and no control measures have been made available. METHODS: The immunofluorescent antibody test (IFAT was used for IgG and IgM anti-Trypanosoma cruzi antibodies in filter paper bloodspot eluates from 128 subjects (73 females, 55 males selected by systematic sampling. Concerning each subject age, gender, birthplace, occupation, duration of residence and building materials used in their houses were recorded. Vectors were captured both in domestic and peridomestic environments. RESULTS: Seropositive, 12.5% (16/128: females, 15.1% (11/73; males, 9.1% (5/55. Average time of residence: 6.1 years for the whole population sample and 7.4 years for the seropositive subjects. Most houses had adobe walls (76.7% , n= 30, galvanized iron rooves (86.7% and earthen floors (53.4% 80% of the walls had crevices. One hundred forty seven specimens of Triatoma infestans were captured, of which 104 (70.7% were domestic, and 1 peridomestic Triatoma sordida. Precipitin host identification: birds, 67.5%; humans, 27.8%; rodents, 11.9%; dogs, 8.7%; cats, 1.6%. House infestation and density indices were 53.3 and 493.0 respectively. We found 21 (14.3% specimens of T. infestans infected with trypanosomes, 18 (85.7% of which in domestic environments. DISCUSSION: The elements for the vector transmission of Chagas disease are present in Avaroa/Primer de Mayo and the ancient custom of keeping guinea pigs indoors adds to the risk of human infection. In neighboring Cochabamba, due to substandard quality control, contaminated blood transfusions are not infrequent, which further aggravates the spread of Chagas disease. Prompt action to check the transmission of this infection, involving additionally the congenital and transfusional

Dengue, Japanese encephalitis and Chikungunya virus antibody prevalence among captive monkey (Macaca nemestrina) colonies of Northern Thailand.

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Nakgoi, Khajornpong; Nitatpattana, Narong; Wajjwalku, Worawidh; Pongsopawijit, Pornsawan; Kaewchot, Supakarn; Yoksan, Sutee; Siripolwat, Voravit; Souris, Marc; Gonzalez, Jean-Paul

2014-01-01

The potential of macaque Macaca nemestrina leonina in Thailand to be infected by endemic arboviruses was assessed. The prevalence of antibodies of three arboviruses actively circulating in Thailand was determined by Plaque Reduction Neutralization assay procedures using samples from captive colonies in Northern Thailand. Out of 38 macaques, 9 (24%) presented reacting antibodies against dengue virus, 5 (13%) against Japanese encephalitis virus, and 4 (10%) against Chikungunya virus. Our results indicate that the northern pig-tailed macaque in Thailand can be infected by these arboviruses, inferring therefore that their virus specific vectors have bitten them. Given that, northern pig-tailed macaque represents an abundant population, living in close range to human or in peridomestic setting, they could play a role as potential reservoir host for arboviruses circulating in Thailand. © 2013 Wiley Periodicals, Inc.

Description of Lutzomyia (Helcocyrtomyia) tolimensis, a new species of phlebotomine sandfly (Diptera: Psychodidae) from Colombia.

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Carrasquilla, María C; Munstermann, Leonard; Marín, Dairo; Ocampo, Clara; Ferro, Cristina

2012-12-01

A description is presented of Lutzomyia tolimensis sp. nov., a new species of the subgenus Helcocyrtomyia, series sanguinaria. It was collected in dwellings, peridomestic environment and in nearby forest patches located in the foothills of the Andean Central Cordillera, where in 2004-2006 occurred the largest epidemic ever recorded of leishmaniasis in Colombia. The male of this species is differentiated from other members of the series sanguinaria based on the following combination of characters: (i) base of coxite with 0-3 subequal setae, (ii) spines of gonostyle organized in positions 2.1.2, (iii) spines inserted on distal half of gonostyle and (iv) relationship of alar indices. The female is recognized principally by the following characters: (i) palpomere V longer than III, (ii) length of labro-epipharynx and (iii) relationship of the alar indices.

Description of Lutzomyia (Helcocyrtomyia) tolimensis, a new species of phlebotomine sandfly (Diptera: Psychodidae) from Colombia

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Carrasquilla, María C; Munstermann, Leonard; Marín, Dairo; Ocampo, Clara; Ferro, Cristina

2016-01-01

A description is presented of Lutzomyia tolimensis sp. nov., a new species of the subgenus Helcocyrtomyia, series sanguinaria. It was collected in dwellings, peridomestic environment and in nearby forest patches located in the foothills of the Andean Central Cordillera, where in 2004–2006 occurred the largest epidemic ever recorded of leishmaniasis in Colombia. The male of this species is differentiated from other members of the series sanguinaria based on the following combination of characters: (i) base of coxite with 0–3 subequal setae, (ii) spines of gonostyle organized in positions 2.1.2, (iii) spines inserted on distal half of gonostyle and (iv) relationship of alar indices. The female is recognized principally by the following characters: (i) palpomere V longer than III, (ii) length of labro-epipharynx and (iii) relationship of the alar indices. PMID:23295748

INTERIM ANALYSIS OF THE CONTRIBUTION OF HIGH-LEVEL EVIDENCE FOR DENGUE VECTOR CONTROL.

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Horstick, Olaf; Ranzinger, Silvia Runge

2015-01-01

This interim analysis reviews the available systematic literature for dengue vector control on three levels: 1) single and combined vector control methods, with existing work on peridomestic space spraying and on Bacillus thuringiensis israelensis; further work is available soon on the use of Temephos, Copepods and larvivorous fish; 2) or for a specific purpose, like outbreak control, and 3) on a strategic level, as for example decentralization vs centralization, with a systematic review on vector control organization. Clear best practice guidelines for methodology of entomological studies are needed. There is a need to include measuring dengue transmission data. The following recommendations emerge: Although vector control can be effective, implementation remains an issue; Single interventions are probably not useful; Combinations of interventions have mixed results; Careful implementation of vector control measures may be most important; Outbreak interventions are often applied with questionable effectiveness.

Lutzomyia sand flies (Diptera: Psychodidae) from middle and lower Putumayo Department, Colombia, with new records to the country.

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Barreto, M; Burbano, M E; Barreto, P

2000-01-01

A total of 4,840 phlebotomine sand flies from 54 localities in Putumayo department (=state), in the Colombian Amazon region, were collected in Shannon traps, CDC light traps, resting places and from human baits. At least 42 Lutzomyia species were registered for the first time to the department. Psychodopygus and Nyssomyia were the subgenera with the greatest number of taxa, the most common species being L. (N.) yuilli and L. (N.) pajoti. They were sympatric in a wide zone of Putumayo, indicating that they should be treated as full species (new status). Among the anthropophilic sand flies, L. gomezi and L. yuilli were found in intradomiciliar, peridomestic, urban or forest habitats. L. richardwardi, L. claustrei, L. nocticola and L. micropyga are reported for the first time in the Colombian Amazon basin. L. pajoti, L. sipani and L. yucumensis are new records for Colombia.

Epidemiología de la enfermedad de Chagas, Departamento General Paz, Argentina Chagas' disease epidemiology in the province of General Paz, Argentina

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Elena B Oscherov

2003-02-01

Full Text Available OBJETIVO: El objetivo del presente trabajo fue investigar la colonización por triatominos en ambientes domésticos y peridomésticos y evaluar la seroprevalencia de infectados chagásicos en localidades rurales. MÉTODOS: La investigación se realizó en General Paz, Corrientes, Argentina. Las viviendas y peridomicilios se seleccionaron mediante un muestreo simple al azar. La búsqueda de triatominos se efectuó por el método captura/hora/hombre. Los insectos se identificaron taxonómicamente y se clasificaron según sexo y edad. La infección por Trypanosoma cruzi se detectó por observación directa de las heces al microscopio y por la técnica de la reacción en cadena de la polimerasa (PCR. Se evaluaron serológicamente a pobladores voluntarios mediante las técnicas de hemaglutinación indirecta (HAI y ensayo inmunoenzimático (ELISA. Se hallaron los índices de infestación, densidad, colonización, infección natural y dispersión. RESULTADOS: Se analizaron 42 viviendas y 50 peridomicilios. En el domicilio los índices de infestación e infección de Triatoma infestans fueron 23,8 y 19,4 respectivamente. Los índices de densidad, colonización y dispersión fueron 2,1; 47,0 y 50,0 respectivamente. La infestación del peridomicilio por T. infestans fue 5,9% y por T. sordida 11,8%. T. sordida resultó infectada por Trypanosoma cruzi en un 2,0%. La seroprevalencia al T. cruzi de los 85 pacientes fue del 22,3%. CONCLUSIONES: Se estima que en el área investigada la transmisión del T. cruzi está interrumpida. Sin embargo, la presencia de infectados humanos y de T. infestans parasitadas posibilitan el reinicio del ciclo de transmisión. Se proponen acciones de rociado con insecticidas con el objeto de eliminar las poblaciones del vector.OBJECTIVE: The aim of this study was to evaluate triatomine colonization in domestic and peridomestic ecotopes and to assess the seroprevalence of Chagas' disease in rural areas. METHODS: The study was

Evaluation of a peridomestic mosquito trap for integration into an Aedes aegypti (Diptera: Culicidae) push-pull control strategy.

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Salazar, Ferdinand V; Achee, Nicole L; Grieco, John P; Prabaripai, Atchariya; Eisen, Lars; Shah, Pankhil; Chareonviriyaphap, Theeraphap

2012-06-01

We determined the feasibility of using the BG-Sentinel™ mosquito trap (BGS) as the pull component in a push-pull strategy to reduce indoor biting by Aedes aegypti. This included evaluating varying numbers of traps (1-4) and mosquito release numbers (10, 25, 50, 100, 150, 200, and 250) on recapture rates under screen house conditions. Based on these variations in trap and mosquito numbers, release intervals were rotated through a completely randomized design with environmental factors (temperature, relative humidity, and light intensity) and monitored throughout each experiment. Data from four sampling time points (05:30, 09:30, 13:30, and 17:30) indicate a recapture range among treatments of 66-98%. Furthermore, 2-3 traps were as effective in recapturing mosquitoes as 4 traps for all mosquito release numbers. Time trends indicate Day 1 (the day the mosquitoes were released) as the "impact period" for recapture with peak numbers of marked mosquitoes collected at 09:30 or 4 h post-release. Information from this study will be used to guide the configuration of the BGS trap component of a push-pull vector control strategy currently in the proof-of-concept stage of development in Thailand and Peru. © 2012 The Society for Vector Ecology.

Evaluation of electron beam radiation effects in the incorporation of Piassava fibers (Attalea funifera Mart.) on ethylene vinyl alcohol copolymer (EVOH)

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Nogueira, Beatriz Ribeiro

2012-01-01

The aim of this work is to explore the contribution of ionizing radiation in the incorporation of piassava fibers (derived from wastes from broom factories) in the ethylene vinyl alcohol copolymer (EVOH), to obtain a composite material, E VOH-Piassava , for packaging applications. The interest in this fiber is due to its inherent properties and morphology as well as being biodegradable. The EVOH composite reinforced with 5% or 10%, by weight of piassava fiber powder with a particle size equal to or less than 125 μm, untreated or treated with 1% silane, were obtained by extrusion, using a twin screw extruder. For carrying out the tensile tests and oxygen barrier of the materials obtained, films were produced from composite materials and EVOH resin was obtained using the process of flat extrusion. Samples of EVOH and the composites were irradiated using an electron accelerator, at doses from 0 to 500 kGy. The results of SEM analysis and X-ray diffraction of composites suggest a good fiber-matrix adhesion, which can be also confirmed by its higher tensile strength at break, compared to that of neat EVOH. The results showed that the incorporation of piassava fibers can promote better oxygen barrier compared to the neat EVOH, in conditions of high humidity. It was observed that, after irradiation, the EVOH film showed better oxygen barrier in high humidity condition, when compared to the non-irradiated EVOH under the same condition, indicating radiation as an effective treatment to improve oxygen barrier in the studied conditions. (author)

Genotype diversity of Trypanosoma cruzi in small rodents and Triatoma sanguisuga from a rural area in New Orleans, Louisiana.

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Herrera, Claudia P; Licon, Meredith H; Nation, Catherine S; Jameson, Samuel B; Wesson, Dawn M

2015-02-24

Chagas disease is an anthropozoonosis caused by the protozoan parasite Trypanosoma cruzi that represents a major public health problem in Latin America. Although the United States is defined as non-endemic for Chagas disease due to the rarity of human cases, the presence of T. cruzi has now been amply demonstrated as enzootic in different regions of the south of the country from Georgia to California. In southeastern Louisiana, a high T. cruzi infection rate has been demonstrated in Triatoma sanguisuga, the local vector in this area. However, little is known about the role of small mammals in the wild and peridomestic transmission cycles. This study focused on the molecular identification and genotyping of T. cruzi in both small rodents and T. sanguisuga from a rural area of New Orleans, Louisiana. DNA extractions were prepared from rodent heart, liver, spleen and skeletal muscle tissues and from cultures established from vector feces. T. cruzi infection was determined by standard PCR using primers specific for the minicircle variable region of the kinetoplastid DNA (kDNA) and the highly repetitive genomic satellite DNA (satDNA). Genotyping of discrete typing units (DTUs) was performed by amplification of mini-exon and 18S and 24Sα rRNA genes and subsequent sequence analysis. The DTUs TcI, TcIV and, for the first time, TcII, were identified in tissues of mice and rats naturally infected with T. cruzi captured in an area of New Orleans, close to the house where the first human case of Chagas disease was reported in Louisiana. The T. cruzi infection rate in 59 captured rodents was 76%. The frequencies of the detected DTUs in such mammals were TcI 82%, TcII 22% and TcIV 9%; 13% of all infections contained more than one DTU. Our results indicate a probable presence of a considerably greater diversity in T. cruzi DTUs circulating in the southeastern United States than previously reported. Understanding T. cruzi transmission dynamics in sylvatic and peridomestic cycles

Transmission of Leishmania infantum in the Canine Leishmaniasis Focus of Mont-Rolland, Senegal: Ecological, Parasitological and Molecular Evidence for a Possible Role of Sergentomyia Sand Flies.

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Massila Wagué Senghor

2016-11-01

Full Text Available Leishmania (L. infantum is the causative agent in an endemic focus of canine leishmaniasis in the Mont-Rolland district (Thiès, Senegal. In this area, the transmission cycle is well established and more than 30% of dogs and 20% of humans are seropositive for L. infantum. However, the sand fly species involved in L. infantum transmission cycle are still unknown. Between 2007 and 2010, 3654 sand flies were collected from different environments (indoor, peridomestic, farming and sylvatic areas to identify the main L. infantum vector(s. Nine sand fly species were identified. The Phlebotomus genus (n = 54 specimens; Phlebotomus (Ph duboscqi and Phlebotomus (Ph. rodhaini was markedly under-represented in comparison to the Sergentomyia genus (n = 3600 specimens; Sergentomyia (Se adleri, Se. clydei, Se. antennata, Se. buxtoni, Se. dubia, Se. schwetzi and Se. magna. Se. dubia and Se. schwetzi were the dominant species indoor and in peridomestic environments, near humans and dogs. Blood-meal analysis indicated their anthropophilic behavior. Some Se. schwetzi specimens fed also on dogs. The dissection of females in the field allowed isolating L. infantum from sand flies of the Sergentomyia genus (0.4% of Se. dubia and 0.79% of Se. schwetzi females. It is worth noting that one Se. dubia female not engorged and not gravid revealed highly motile metacyclic of L. infantum in the anterior part of the midgut. PCR-based diagnosis and sequencing targeting Leishmania kinetoplast DNA (kDNA highlighted a high rate of L. infantum-positive females (5.38% of Se. dubia, 4.19% of Se. schwetzi and 3.64% of Se. magna. More than 2% of these positive females were unfed, suggesting the parasite survival after blood-meal digestion or egg laying. L. infantum prevalence in Se. schwetzi was associated with its seroprevalence in dogs and humans and L. infantum prevalence in Se. dubia was associated with its seroprevalence in humans. These evidences altogether strongly suggest that

Prevalence of antibodies to Japanese encephalitis virus among pigs in Bali and East Java, Indonesia, 2008.

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Yamanaka, Atsushi; Mulyatno, Kris Cahyo; Susilowati, Helen; Hendrianto, Eryk; Utsumi, Takako; Amin, Mochamad; Lusida, Maria Inge; Soegijanto, Soegeng; Konishi, Eiji

2010-01-01

Japanese encephalitis virus (JEV) is a fatal disease in Asia. Pigs are considered to be the effective amplifying host for JEV in the peridomestic environment. Bali Island and Java Island in Indonesia provide a model to assess the effect of pigs on JEV transmission, since the pig density is nearly 100-fold higher in Bali than Java, while the geographic and climatologic environments are equivalent in these areas. We surveyed antibodies to JEV among 123 pigs in Mengwi (Bali) and 96 pigs in Tulungagung (East Java) in 2008 by the hemagglutination-inhibition (HAI) test. Overall prevalences were 49% in Bali and 6% in Java, with a significant difference between them (P Java. In addition, 2-mercaptoethanol-sensitive antibodies were found only from Bali samples. Further, the average HAI antibody titer obtained from positive samples was significantly higher in Bali (1:52) than Java (1:10; P Java.

Ecohealth Interventions Limit Triatomine Reinfestation following Insecticide Spraying in La Brea, Guatemala

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Lucero, David E.; Morrissey, Leslie A.; Rizzo, Donna M.; Rodas, Antonieta; Garnica, Roberto; Stevens, Lori; Bustamante, Dulce M.; Monroy, Maria Carlota

2013-01-01

In this study, we evaluate the effect of participatory Ecohealth interventions on domestic reinfestation of the Chagas disease vector Triatoma dimidiata after village-wide suppression of the vector population using a residual insecticide. The study was conducted in the rural community of La Brea, Guatemala between 2002 and 2009 where vector infestation was analyzed within a spatial data framework based on entomological and socio-economic surveys of homesteads within the village. Participatory interventions focused on community awareness and low-cost home improvements using local materials to limit areas of refuge and alternative blood meals for the vector within the home, and potential shelter for the vector outside the home. As a result, domestic infestation was maintained at ≤ 3% and peridomestic infestation at ≤ 2% for 5 years beyond the last insecticide spraying, in sharp contrast to the rapid reinfestation experienced in earlier insecticide only interventions. PMID:23382173

Chandipura virus infection causing encephalitis in a tribal population of Odisha in eastern India.

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Dwibedi, Bhagirathi; Sabat, Jyotsnamayee; Hazra, Rupenangshu K; Kumar, Anu; Dinesh, Diwakar Singh; Kar, Shantanu K

2015-01-01

The sudden death of 10 children in a tribal village of Kandhamal district, Odisha in eastern India led to this investigation. We conducted a door-to-door survey to identify cases. Antibodies for Chandipura, Japanese encephalitis, dengue, chikungunya and West Nile viruses were tested by ELISA in probable cases. Chandipura virus RNA was tested from both human blood samples and sand flies by reverse transcriptase polymerase chain reaction. We conducted vector surveys in domestic and peridomestic areas, and collected sand flies. Entomological investigations revealed the presence of Phlebotomus argentipes and Sergentomiya sp. Thirty-five patients presented with fever, 12 of them had altered sensorium including 4 who had convulsions. The blood samples of 21 patients were tested; four samples revealed Chandipura virusspecific IgM antibody. Chandipura virus infection causing encephalitis affected this tribal population in eastern India at 1212 m above sea level. Copyright 2015, NMJI.

Estudo morfométrico do gênero Panstrongylus Berg, 1879 (Hemiptera, Reduviidae, Triatominae Morphometric study of the genus Panstrongylus Berg, 1879 (Hemiptera, Reduviidae, Triatominae

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Carolina Magalhães dos Santos

2003-10-01

Full Text Available The subfamily Triatominae is actually represented by 137 species distributed among 6 tribes and 19 genera. Within this subfamily, the genus Panstrongylus, Berg 1879, is composed by 13 species widespread in sylvatic, peridomestic, and domestic habitats of Neotropical regions. These species are vectors of Chagas disease and consequently are found associated with its main hosts, such as birds and mammals. Interest in species of this genus has been increasing in the last few years. Reports of several authors indicate these Triatominae to invade and colonize houses, increasing their epidemiological significance. Morphometry was used in this study to investigate correlations among possible closely related species. We measured 224 specimens among 13 species through a set of metric variables of the head. The results indicated that the genus Panstrongylus seems to be homogeneous since 10 of the 14 species were shown to be closely related.

Avaliação da inibição da acetilcolinesterase por extratos de plantas medicinais Evaluation of acetylcholinesterase inhibition by extracts from medicinal plants

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W.M. Mota

2012-01-01

Full Text Available Neste trabalho foi avaliada a atividade inibitória da acetilcolinesterase (AChE pelo método de Ellman, modificado por Rhee, de extratos aquosos e etanólicos de oito plantas utilizadas na medicina popular da região Nordeste do Brasil. O extrato aquoso de E. velutina não apresentou atividade inibitória enquanto o extrato aquoso de Maytenus rigida apresentou baixa atividade inibitória (percentual de inibição de 4%. Detectou-se atividade inibitória moderada com o extrato aquoso de P. piperoides (percentual de inibição de 40 %, enquanto o extrato de V. agnus-castus L. inibiu 74% da atividade da AChE, caracterizando-se como potente atividade inibitória. A avaliação da inibição da AChE com os extratos etanólicos demonstrou que os extratos de Sideroxylon obtusifolium, Erythrina velutina, Vitex agnus-castus, Phoradendron piperoides, Chrysobalanus icaco, Bauhinia cheilantha e Orbignya phalerata não apresentaram atividade inibitória. Baixa atividade inibitória foi observada com os extratos etanólicos de Maytenus rigida (percentual de inibição de 7% e de Hyptis fruticosa (percentual de inibição de 11%. O extrato etanólico de Moringa oleifera apresentou atividade inibitória moderada, inibindo 47% da atividade dessa enzima. Nenhum dos extratos etanólicos testados apresentou atividade inibitória potente da AChE. Os resultados dos estudos de inibição da acetilcolinesterase permitem concluir que o extrato aquoso de V. agnus-castus L. mostrou-se o mais eficaz quanto a inibição da AChE. Este resultado reforça a necessidade da continuidade do estudo desse extrato, de forma a realizar a partição do extrato e a purificação das frações para isolar a molécula responsável pela inibição observada.In this study, we evaluated the inhibitory activity against acetylcholinesterase (AChE according to Ellman's method, modified by Rhee, for ethanol and aqueous extracts from eight plants used in folk medicine in the northeast region of

The importance of the opossum (Didelphis albiventris as a reservoir for Trypanosoma cruzi in Bambuí, Minas Gerais state

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Alexandre José Fernandes

1991-03-01

Full Text Available In a survey realized on the sylvatic and peridomestic environment at Bambuí county, Minas Gerais State, 44 (37.9% out of 116 opossums (Didelphis albiventris captured were found to be naturally infected with Trypanosoma cruzi. One handred and forty three parasite samples were obtanied from 43 infected opossums using simultaneously hemoculture, xenodiagnosis (Triatoma infestans, Panstrongylus megistus and Rhodnius neglectus and examination of anal glands contents. The parasite samples were characterized according to six isoenzyme patterns. All samples, independently of the method of isolation, presented an isoenzyme pattern similar to the standard T. cruzi Z1, showing that either xenodiagnosis or hemoculture can used without selecting parasite subpopulation from naturally infected opossums. Preveous isoenzyme patterns reported for human T.cruzi isolates from same region were completely different. This isoenzyme dissimilarity between sylvatic and domiciliar environments suggests the existence of two independent T. cruzi transmission cycles in Bambuí. The epidemiological implicatinos of these results are discussed.

Cytokine and Phenotypic Cell Profiles of Leishmania infantum Infection in the Dog

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Carla Maia

2012-01-01

Full Text Available Leishmaniasis has reemerged in recent years showing a wider geographic distribution and increased global incidence of human and canine disease than previously known. Dogs are the main domestic/peridomestic reservoir hosts of zoonotic visceral leishmaniasis caused by Leishmania infantum. Since the evolution of leishmaniasis and clinical appearance is a consequence of complex interactions between the parasite and host immune response, a profound knowledge about the immune profile developed in dog's infection is crucial for vaccine and immunomodulatory therapy design. The main goal of this paper is to compile the recent advances made on cytokine and phenotypic cell profiles in different tissues and organs of dogs infected with L. infantum. This paper also stressed that the knowledge of the immune responses developed, namely, in liver, lymph node, and spleen is very limited. All data emphasizes that more research on canine leishmaniasis is necessary for the development of new and efficacious tools to control zoonotic leishmaniasis.

Isolation of Salmonella enterica and serologic reactivity to Leptospira interrogans in opossums (Didelphis virginiana) from Yucatán, México.

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Ruiz-Pina, Hugo Antonio; Puc-Franco, Miguel Angel; Flores-Abuxapqui, Javier; Vado-Solis, Ignacio; Cardenas-Marrufo, María Fidelia

2002-01-01

The presence of Salmonella enterica and serologic evidence of infection by Leptospira interrogans, were detected in the opossum Didelphis virginiana in a semi-urban locality of the Yucatán State, México. Ninety-one opossums were captured during the period April 1996 and May 1998. From a total of 17 feces samples, four Salmonella enterica subsp. enterica serotypes (Sandiego, Newport, Anatum, and Minnesota), and one Salmonella enterica subsp. arizonae serovar O44:Z4,Z23:- were isolated. Some opossums presented mixed infections. From 81 sera samples, four (4.9%) were positive to antibodies to Leptospira serovars pomona and wolfii. Both animals infected with Salmonella enterica and those serologically positive to Leptospira interrogans were captured in peridomestic habitat. Opossums infected with Salmonella enterica, were captured in dry season, and those seropositive to Leptospira interrogans during the rainy season. The implications of infection and reactivity of these zoonotic pathogens in D. virginiana in the Yucatan state are briefly discussed.

Identification of Blood Meals from Potential Arbovirus Mosquito Vectors in the Peruvian Amazon Basin.

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Palermo, Pedro M; Aguilar, Patricia V; Sanchez, Juan F; Zorrilla, Víctor; Flores-Mendoza, Carmen; Huayanay, Anibal; Guevara, Carolina; Lescano, Andrés G; Halsey, Eric S

2016-11-02

The transmission dynamics of many arboviruses in the Amazon Basin region have not been fully elucidated, including the vectors and natural reservoir hosts. Identification of blood meal sources in field-caught mosquitoes could yield information for identifying potential arbovirus vertebrate hosts. We identified blood meal sources in 131 mosquitoes collected from areas endemic for arboviruses in the Peruvian Department of Loreto by sequencing polymerase chain reaction amplicons of the cytochrome b gene. Psorophora (Janthinosoma) albigenu, Psorophora (Grabhamia) cingulata, Mansonia humeralis, Anopheles oswaldoi s.l., and Anopheles benarrochi s.l. had mainly anthropophilic feeding preferences; Aedes (Ochlerotatus) serratus, and Aedes (Ochlerotatus) fulvus had feeding preferences for peridomestic animals; and Culex (Melanoconion) spp. fed on a variety of vertebrates, mainly rodents (spiny rats), birds, and amphibians. On the basis of these feeding preferences, many mosquitoes could be considered as potential enzootic and bridge arbovirus vectors in the Amazon Basin of Peru. © The American Society of Tropical Medicine and Hygiene.

Abundance, Natural Infection with Trypanosomes, and Food Source of an Endemic Species of Triatomine, Panstrongylus howardi (Neiva 1911), on the Ecuadorian Central Coast

Science.gov (United States)

Villacís, Anita G.; Ocaña-Mayorga, Sofía; Lascano, Mauricio S.; Yumiseva, César A.; Baus, Esteban G.; Grijalva, Mario J.

2015-01-01

The elimination of domestic triatomines is the foundation of Chagas disease control. Regional initiatives are eliminating introduced triatomine species. In this scenario, endemic triatomines can occupy the ecological niches left open and become a threat to long-term Chagas disease control efforts. This study determined the abundance, colonization, and Trypanosoma cruzi infection rate of the endemic Panstrongylus howardi in 10 rural communities located in Ecuador's Manabí Province. In total, 518 individuals of P. howardi were collected. Infestation indices of 1.4% and 6.6% were found in the domestic and peridomestic environments, respectively. We determined a T. cruzi infection rate of 53.2% (N = 47) in this species. P. howardi has a high capacity to adapt to different habitats, especially in the peridomicile. This implies a considerable risk of transmission because of the frequency of intradomicile invasion. Therefore, this species needs to be taken into account in Chagas control and surveillance efforts in the region. PMID:25385867

Genetic structure of local populations of Lutzomyia longipalpis (Diptera: Psychodidae) in central Colombia.

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Munstermann, L E; Morrison, A C; Ferro, C; Pardo, R; Torres, M

1998-01-01

Lutzomyia longipalpis (Lutz & Neiva), the sand fly vector of American visceral leishmaniasis in the New World tropics, has a broad but discontinuous geographical distribution from southern Mexico to Argentina. A baseline for population genetic structure and genetic variability for this species was obtained by analyzing 5 local, peridomestic populations at the approximate center of its distribution, the Magdalena River Valley of central Colombia. Three populations of L. longipalpis from El Callejón, a small rural community, were compared with 2 populations from neighboring areas 12 and 25 km distant for genetic variation at 15 isoenzyme loci. The mean heterozygosity ranged from 11 to 16%, with 1.2 to 2.3 alleles detected per locus. Nei's genetic distances among the populations were very low, ranging from 0.001 to 0.007. Gene flow estimates based on FST indicated high levels of gene flow among local L. longipalpis populations, with minimal population substructuring.

The Biology of the Triatomine Bugs Native to South Central Texas and Assessment of the Risk They Pose for Autochthonous Chagas Disease Exposure.

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Wozniak, Edward J; Lawrence, Gena; Gorchakov, Rodion; Alamgir, Hasanat; Dotson, Ellen; Sissel, Blake; Sarkar, Sahotra; Murray, Kristy O

2015-10-01

Triatomine bugs are a group of hematophagous arthropods that can serve as biological vectors for Trypanosoma cruzi , the etiological agent of American trypanosomiasis (Chagas disease). Because of differences in the biology and feeding habits among triatomine species, some are more likely than others to be involved in zoonotic and/or human-to-human transmission cycles of T. cruzi . In an attempt to assess the risk for Chagas disease exposure in south-central Texas, human habitations across Texas Health Service Region 8 (HSR 8) and surrounding counties were surveyed for triatomines to characterize the geographic distribution, species-specific biology, and T. cruzi -infection prevalence better. Between May 2010 and August 2013, a total of 545 triatomines representing all 5 known indigenous species (Triatoma gerstaeckeri, Triatoma indictiva, Triatoma lecticularia, Triatoma sanguisuga, and Triatoma protracta woodi) were collected from 59 sites across the region. Triatoma gerstaeckeri was the species most commonly found in domestic and peridomestic ecotopes across Texas HSR 8, representing over 80% of the triatomines collected. Adult T. gerstaeckeri exhibited a seasonal dispersal pattern that began in late April, peaked in mid-May, and then continued into August. On homes with available crevices in the exterior walls, adult T. gerstaeckeri were observed emerging from or entering these protective microhabitats, suggesting possible opportunistic colonization of some exterior walls compartments. Laboratory testing of triatomine hindgut contents for T. cruzi by PCR demonstrated the adult T. gerstaeckeri-infection prevalence across Texas HSR 8 to be 64%. Monitoring peridomestic adult T. gerstaeckeri over the seasonal dispersal peak demonstrated statistically significant increases in both their T. cruzi -infection prevalence (P < 0.01) and tendency to invade human dwellings (P < 0.01) in the later aspect of the emergence peak. In addition to the adult insects, variably sized

Chemical Composition and Antimicrobial Potential of Palm Leaf Extracts from Babaçu (Attalea speciosa, Buriti (Mauritia flexuosa, and Macaúba (Acrocomia aculeata

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Adriana Idalina Torcato de Oliveira

2016-01-01

Full Text Available Babaçu (A. speciosa, Buriti (M. flexuosa, and Macaúba (A. aculeata are palm trees typical of the ecotone area between Cerrado and the Amazon rainforest. The purpose of this study was to evaluate the antimicrobial potential of the extracts prepared from the leaves of those palms as well as determine their chemical compositions. The ethanol extracts were prepared in a Soxhlet apparatus and tested by disk diffusion and agar dilution technique against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida parapsilosis. However, there was no significant activity at concentrations of 25, 50, and 100 mg·Ml−1. Moreover, the phytochemical analysis revealed the presence of tannins, flavonoids, catechins, steroids, triterpenes, and saponins. Gas chromatography (GC/MS analysis also identified organic acids, such as capric (decanoic acid, lauric (dodecanoic acid, myristic (tetradecanoic acid, phthalic (1,2-benzenedicarboxylic acid, palmitic (hexadecanoic acid, stearic (octadecanoic acid, linoleic (9,12-octadecadienoic acid (omega-6, linolenic (octadecatrienoic acid (omega-3, and the terpenes citronellol and phytol. Based on the chemical composition in the palm leaf extracts, the palms have the potential to be useful in the food, cosmetic, and pharmaceutical industries.

Pollination ecology of the Gray Nicker Caesalpinia crista (Caesalpiniaceae a mangrove associate at Coringa Mangrove Forest, Andhra Pradesh, India

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P.S. Raju

2014-09-01

Full Text Available Caesalpinia crista L., commanly known as Gray Nicker, is an oligohaline mangrove associate confined to landward marginal areas of the Coringa Mangrove Forest, Andhra Pradesh, India. The flowering occurs during the wet season from June to November. The flowers are hermaphroditic, self-compatible and exhibit a mixed breeding system. The floral characteristics that constitute melittophilous pollination syndrome include diurnal anthesis, slight fragrance, zygomorphy, yellow petals, with a flag petal displaying a conspicuous nectar guide, and the presence of nectar with a high sugar concentration. Extra-floral nectar along the rachis is an additional attractant and is easily perceivable by bees. The plant is pollinated almost exclusively by bees, especially carpenter bees. The floral characteristics such as free petals, fully exposed stamens with dry and powdery pollen grains and hairy stigma facilitate anemophily which is effective due to high winds during the rainy season. The prolific growth and near synchronous flowering at population level contribute to pollen availability in huge quantities and enable anemophily as an effective mode of pollination. The functionality of melittophily and anemophily together constitutes ambophily. Hand-pollination experiments indicated that the plant is principally out-crossing. The natural fruit set does not exceed 10%; this lowest percentage could be partly due to flower-feeding by the beetle, Mylabris phalerata. The fruits are indehiscent, 1-seeded, which are buoyant and are not dispersed far away from the parental sites. The viable seeds produce new plants in the vicinity of parental plants during the rainy season. This plant builds up its population as small patches or in pure stands and hence is important in building landward mangrove cover.

Ecological interactions among phlebotomines (Diptera: Psychodidae) in an agroforestry environment of northeast Brazil.

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Pinheiro, Marcos Paulo Gomes; Silva, José Hilário Tavares; Cavalcanti, Katrine Bezerra; de Azevedo, Paulo Roberto Medeiros; de Melo Ximenes, Maria de Fátima Freire

2013-12-01

Phlebotomine vectors transmit parasites and can cause visceral leishmaniasis (VL) or cutaneous leishmaniasis (TL). Phlebotomine females are hematophagous but need to ingest carbohydrates, possibly promoting the development of protozoan parasites in their digestive tract. The present study evaluated the species composition and abundance across several habitats in a metropolitan landscape, as well as associations among phlebotomines, plants, and local climatic parameters. Three consecutive monthly collections were carried out in an Atlantic Forest fragment, using CDC light traps in peridomestic areas and cashew, coconut, and mango tree. plantations. Eight species of phlebotomine were captured: Evandromyia evandroi, Lutzomyia longipalpis, Psathyromyia shannoni, Sciopemyia sordellii, Evandromyia walkeri, Psychodopygus wellcomei, Nyssomyia whitmani, and Nyssomyia intermedia, primarily from the forest environment. L. longipalpis was confirmed as a species adapted to anthropic environments, while P. wellcomei was shown to be predominately forest-dwelling. Phlebotomines exhibited diversified food consumption patterns in relation to carbohydrate sources. They fed on both native and exotic species of arboreal and shrubby vegetables and gramineous plants. © 2013 The Society for Vector Ecology.

Malaria: Knowledge and prevention practices among school adolescents in a coastal community in Calabar, Nigeria

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Ndifreke E. Udonwa

2010-04-01

Objectives: To determine the malaria prevention practices of school adolescents in the coastal community of Calabar, Nigeria. Method: This was a cross-sectional survey involving secondary schools in southern Calabar. Four hundred adolescents were randomly selected from the 4565 learners in 5 out of 17 secondary schools in southern Calabar, Cross River State, Nigeria. A self-administered, semi-structured questionnaire was administered to the respondents. Results: Most respondents (77.5% were aware that the vector transmits the malaria parasite through biting. Fewer respondents would prevent malaria attacks by clearing the vegetation in the peri-domestic environment (13.5%, filling up potholes (16.9%, opening up drainage (11%, using insecticide-treated nets (25.7% or using antimalarial drugs (11.2%. Less than one-tenth (8% would use various other methods such as not accepting unscreened blood, while only 11% obtained the information from their teachers. Conclusion: The study identified knowledge gaps among school children. There is a need to empower teachers with information about the cause of malaria and prevention strategies.

Indoor-breeding of Aedes albopictus in northern peninsular Malaysia and its potential epidemiological implications.

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Dieng, Hamady; Saifur, Rahman G M; Hassan, Ahmad Abu; Salmah, M R Che; Boots, Michael; Satho, Tomomitsu; Jaal, Zairi; AbuBakar, Sazaly

2010-07-27

The mosquito Ae. albopictus is usually adapted to the peri-domestic environment and typically breeds outdoors. However, we observed its larvae in most containers within homes in northern peninsular Malaysia. To anticipate the epidemiological implications of this indoor-breeding, we assessed some fitness traits affecting vectorial capacity during colonization process. Specifically, we examined whether Ae. albopictus exhibits increased survival, gonotrophic activity and fecundity due to the potential increase in blood feeding opportunities. In a series of experiments involving outdoors and indoors breeding populations, we found that Ae. albopictus lives longer in the indoor environment. We also observed increased nighttime biting activity and lifetime fecundity in indoor/domestic adapted females, although they were similar to recently colonized females in body size. Taken together these data suggest that accommodation of Ae. albopictus to indoor/domestic environment may increase its lifespan, blood feeding success, nuisance and thus vectorial capacity (both in terms of increased vector-host contacts and vector population density). These changes in the breeding behavior of Ae. albopictus, a potential vector of several human pathogens including dengue viruses, require special attention.

Differentiation of Aedes aegypti and Aedes notoscriptus (Diptera: Culicidae) eggs using scanning electron microscopy.

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Faull, Katherine J; Williams, Craig R

2016-05-01

Aedes notoscriptus and Aedes aegypti are both peri-domestic, invasive container-breeding mosquitoes. While the two potential arboviral vectors are bionomically similar, their sympatric distribution in Australia is limited. In this study, analyses of Ae. aegypti and Ae. notoscriptus eggs were enabled using scanning electron microscopy. Significant variations in egg length to width ratio and outer chorionic cell field morphology between Ae. aegypti and Ae. notoscriptus enabled distinction of the two species. Intraspecific variations in cell field morphology also enabled differentiation of the separate populations of both species, highlighting regional and global variation. Our study provides a comprehensive comparative analysis of inter- and intraspecific egg morphological and morphometric variation between two invasive container-breeding mosquitoes. The results indicate a high degree of intraspecific variation in Ae. notoscriptus egg morphology when compared to the eggs of Ae. aegypti. Comparative morphological analyses of Ae. aegypti and Ae. notoscriptus egg attributes using SEM allows differentiation of the species and may be helpful in understanding egg biology in relation to biotope of origin. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rattus norvegicus (Rodentia: Muridae Infected by Leishmania (Leishmania infantum (syn. Le. chagasi in Brazil

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Fabiana de Oliveira Lara-Silva

2014-01-01

Full Text Available In the present study we surveyed the fauna of phlebotomine sand flies and small mammals in peridomestic areas from a Brazilian municipality where the American cutaneous leishmaniasis (ACL is endemic. A total of 608 female phlebotomine sand flies were captured during nine months in 2009 and 2010. Seven different species were represented with 60% of them being Lutzomyia intermedia and Lu. whitmani, both incriminated vectors of ACL. Lu. longipalpis, a proven vector of visceral leishmaniasis (VL was also captured at high proportion (12.8%. Genomic DNA analysis of 136 species-specific pools of female sand flies followed by molecular genotyping showed the presence of Leishmania infantum DNA in two pools of Lu. longipalpis. The same Leishmania species was found in one blood sample from Rattus norvegicus among 119 blood and tissue samples analysed. This is the first report of Le. infantum in R. norvegicus in the Americas and suggests a possible role for this rodent species in the zoonotic cycle of VL. Our study coincided with the reemergence of VL in Governador Valadares.

Propriedades da carne e perfil de ácidos graxos do pernil de catetos (Tayassu tajacu) alimentados com torta de babaçu (Orbignya phalerata)

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Albuquerque,N.I.; Contreras,C.C.; Alencar,S.; Meirelles,C.F.; Aguiar,A.P.; Moreira,J.A.; Packer,I.U.

2009-01-01

Analisaram-se as propriedades da carne e o perfil de ácidos graxos do pernil de catetos alimentados com dietas contendo diferentes porcentagens de torta de babaçu, usada como fonte energética alternativa substituindo parte do milho na alimentação, em sistemas de produção em cativeiro. Avaliou-se o pernil de 12 animais quanto às suas propriedades - perda de peso ao cozimento, força de cisalhamento, pH e capacidade de retenção de água-, depois extraiu-se o óleo da carne e determinou-se o perfil...

Cantharidin Inhibits the Growth of Triple-Negative Breast Cancer Cells by Suppressing Autophagy and Inducing Apoptosis in Vitro and in Vivo

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Hong-chang Li

2017-10-01

Full Text Available Background/Aims: Cantharidin, a type of terpenoid secreted by the blister beetle Mylabris phalerata (Pallas, has attracted great attention in cancer therapy because of its potential anti-cancer activities. Here, we report the effects on apoptosis and autophagy in human triple-negative breast cancer (TNBC cell lines after treatment with cantharidin and attempt to elucidate the underlying mechanisms. Methods: MDA-MB-231 and MDA-MB-468 cells were treated with cantharidin and cell proliferation was examined using CCK-8 and clone formation assays. The expression of apoptosis- and autophagy-associated proteins was detected by western blotting. Cells were infected with lentivirus carrying the Beclin-1 gene, and MDA-MB-231-beclin1 (MB231-Bec and MDA-MB-468-beclin-1(MB468-Bec cells stably expressing Beclin-1 were established. Autophagic vacuoles in cells were observed with LC3 staining using fluorescence microscopy, and apoptotic cells were detected via flow cytometry. Tumor growth was assessed by subcutaneous inoculation of TNBC cells into BALB/c nude mice. Results: Cantharidin inhibited the proliferation of MDA-MB-231 and MDA-MB-468 cells, and induced cell apoptosis. Cantharidin additionally inhibited the conversion of LC3 I to LC3 II and autophagosome formation by suppressing the expression of Beclin-1. Furthermore, overexpression of Beclin-1 in TNBC cells attenuated the cytotoxicity of cantharidin. In vivo, cantharidin inhibited the growth of MDA-MB-231 and MDA-MB-468 xenografts in nude mice by suppressing autophagy and inducing apoptosis, and Beclin-1 overexpression in TNBC cells reduced the efficacy of cantharidin. Conclusions: Cantharidin inhibits autophagy by suppressing Beclin-1 expression and inducing apoptosis of TNBC cells in vitro and in vivo, thereby representing a potential strategy for the treatment of TNBC.

Las palmas entre los grupos cazadores-recolectores de la Amazonia Colombiana

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Morcote Ríos Gaspar

1998-06-01

Full Text Available We compare past and present systems of management of palms in the Colombian Amazon, based on archaeological studies of preceramic groups in the middle Caquetá region and ethnographic research on the nomadic Nukak people, who inhabit northeastern Guaviare department. Astrocaryum aculeatum, Attalea maripe, Mauritia flexuosa, Oenocarpus bataua, Oenocarpus bacaba y Oenocarpus mapora, have been used from the early Holocene through the present time. Among these, Oenocarpus bataua has remained the most important food species. We conclude that one of the mananging strategies of the tropical rain forest is the simultaneous improvement of ecological units, especially in the tertiary sedimentary plains, and that such management probably has a long history in the region.Se presenta una comparación sobre el manejo de las palmas en la Amazonia Colombiana, basado en los resultados de un estudio arqueológico de grupos precerámicos en la región del Medio Caquetá y uno etnográfico del pueblo nómada Nukak que habita la zona nororiental del departamento del Guaviare. Se encontró que Astrocaryum aculeatum, A ttalea maripa, Mauritia flexuosa, Oenocarpus bataua, Oenocarpus bacaba y Oenocarpus mapora son algunas de las palmas usadas desde el Holoceno temprano hasta el presente. Entre estas Oenocarpus bataua es la especie más importante como fuente de alimento. Así mismo, se concluye que una de las estrategias de manejo en el bosque húmedo tropical es el aprovechamiento simultáneo de diferentes unidades ecológicas, con predominio del plano sedimentario terciario. Es probable que este tipo de manejo tenga en la región una larga historia.

[Transmission risk of Trypanosoma cruzi in Metztitlán municipality from Hidalgo state, México, by characterization of domiciliary units and their entomologic indexes].

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Becerril, Marco A; Angeles-Pérez, Vidal; Noguez-García, Julio Cr; Imbert-Palafox, José L

2010-01-01

In order to determine the risk of transmission of Trypanosoma cruzi by triatomines in Metztitlan municipality, Hidalgo State, Mexico, entomological indexes were calculated and the characteristics of dwellings were described. A transversal, retrospective, descriptive, and observational study was performed by means of an intentional not probabilistic and expertise sampling from January to December of 2005 in 10 localities in which presence of triatomines were investigated either intra or peridomestic environmental in 699 houses. Building material and presence of infected triatomines with T. cruzi were registered to determine entomologic indexes. The triatomine species collected were: Triatoma barberi (Usinger) and T. mexicana (Herrich-Schaeffer) (Hemiptera: Reduviidae). The results indicated that natural infection index varied from 7.7% to 50%; colonization index reached 80%; infestation index varied from 7.7% to 25%; dispersion index was 70%. Stone-walled houses were more infested. We can conclude that it is necessary to establish T. cruzi transmission control measures against triatomines in localities from Metztitlan, primarily in stone-walled houses where T. barberi occurs, as it was the most important vector species in the transmission of T. cruzi in this municipality.

Anti-leptospiral agglutinins in marmosets (Saguinus oedipus and Saguinus leucopus from illegal trade

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Viviana Gonzalez-Astudillo

2015-09-01

Full Text Available Objective. Determine the infection status with pathogenic Leptospira of one Saguinus oedipus and nine Saguinus leucopus at the Cali Zoo that had been confiscated in Colombia from illegal trade. Materials and methods. A full physical examination, blood work, urinalysis were conducted in all individuals during the reception health check-up, in addition to running the microagglutination test with a pool of 19 serovars, with a starting dilution of 1:50. Results. A high positive titer (≥1:3200 to Leptospira alexanderi serovar manhao in an asymptomatic S. oedipus was detected. All S. leucopus tested negative or less than 1:50. Conclusions. Captive locations have been documented to artificially enhance opportunities to come into contact with contaminated bodily fluids from peridomestic rodents. However, infectious diseases acquired during the illegal transport of wildlife to major metropolitan centers are rarely considered a wildlife conservation or public health threat. Infection with zoonotic pathogens should also be considered an additional threat to endangered wild primates involved in illegal trade, which could hamper reintroduction efforts or other population management procedures for primate species with restricted and fragmented distributions.

Synanthropic Cockroaches (Blattidae: Periplaneta spp.) Harbor Pathogenic Leptospira in Colombia.

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Gonzalez-Astudillo, Viviana; Bustamante-Rengifo, Javier A; Bonilla, Álvaro; Lehmicke, Anna Joy J; Castillo, Andrés; Astudillo-Hernández, Miryam

2016-01-01

Leptospirosis cases in Colombia are typically linked to peridomestic rodents; however, empirical data suggest that Leptospira-infected patients with no apparent exposure to these reservoirs are common. Cockroaches (Periplaneta spp.) have equal or greater interaction with humans than rodents, yet their potential role as carriers of Leptospira has not been assessed. We determined if pathogenic Leptospira is harbored by Periplaneta spp. in Cali (Colombia) and the variables influencing this relationship. Fifty-nine cockroaches were captured from seven sites and DNA was extracted from the body surface and digestive tract for a multiplex polymerase chain reaction, targeting genes secY and flaB. Logistic regression models and proportion tests showed a higher likelihood for Leptospira to be isolated from body surfaces (P > 0.001) and from individuals inside houses (six times more likely). These findings are the first to demonstrate an association between Periplaneta spp. and Leptospira, suggesting the need to investigate the potential for cockroaches to serve as reservoirs or transport hosts for Leptospira. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evaluation of Mesocyclops aspericornis (Cyclopoida:Cyclopidae) and Toxorhynchites speciosus as integrated predators of mosquitoes in tire habitats in Queensland.

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Brown, M D; Hendrikz, J K; Greenwood, J G; Kay, B H

1996-09-01

This study addressed biological control of peridomestic Aedes notoscriptus, known to be a highly effective colonizer of tire habitats and a possible vector of Ross River virus. A laboratory trial of the compatibility of the predators Mesocyclops aspericornis and Toxorhynchites speciosus in small container habitats showed that 4th-instar Tx. speciosus did not significantly affect M. aspericornis mortality. Introduced M. aspericornis and naturally occurring Tx. speciosus were found to form a compatible predator pair for reduction of larval Ae. notoscriptus and Culex quinquefasciatus populations in tire habitats. Over 22 months of field survey, 97% of tires without predators contained mosquito larvae, at a median density of 43 larvae/liter. By comparison, 51% of tires containing both predator species held mosquito larvae at a median density of 4 larvae/liter. Predation by Tx. speciosus persisted for the duration of the study. The inability of the Lake Kurwongbah strain of M. aspericornis to tolerate temperatures of winter, resulted in a failure to deliver persistent reduction of mosquitoes in tires. The temperature-dependent population characteristics of M. aspericornis emphasize the long-recognized importance of matching a biological control candidate's physiological requirements to the environment in which control is sought.

Initial Assessment of the Acceptability of a Push-Pull Aedes aegypti Control Strategy in Iquitos, Peru and Kanchanaburi, Thailand

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Paz-Soldan, Valerie A.; Plasai, Valaikanya; Morrison, Amy C.; Rios-Lopez, Esther J.; Guedez-Gonzales, Shirly; Grieco, John P.; Mundal, Kirk; Chareonviriyaphap, Theeraphap; Achee, Nicole L.

2011-01-01

As part of a larger research program evaluating chemical threshold levels for a Push-Pull intervention to reduce man-vector (Aedes aegypti) contact, this qualitative study explored local perceptions and strategies associated with mosquito control within dengue-endemic communities in Peru and Thailand. Focus groups were used to provide preliminary information that would identify possible public acceptance issues to the Push-Pull strategy in each site. Nine focus group discussions (total of 102 individuals) conducted between September 2008 and March 2009 examined several themes: 1) current mosquito control practices; 2) perceptions of spatial repellency and contact irritancy versus killing mosquitoes; and 3) initial perceptions toward mosquito host-seeking traps. Results indicate participants use household-level strategies for insect control that reveal familiarity with the concept of spatial repellent and contact irritant actions of chemicals and that placing traps in the peridomestic environment to remove repelled mosquitoes was acceptable. Preliminary evidence suggests a Push-Pull strategy should be well accepted in these locations. These results will be beneficial for developing future large scale push-pull interventions and are currently being used to guide insecticide application strategies in (entomological) proof-of-concept studies using experimental huts. PMID:21292886

An Experimental Test of Factors Attracting Deer Mice into Buildings.

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Kuenzi, Amy J; Douglass, Richard

2009-09-01

Deer mice (Peromyscus maniculatus) are the principal reservoir host of Sin Nombre virus (SNV). Deer mice use a wide variety of habitats including peridomestic settings in and around human dwellings, their presence in and around homes has been implicated as a risk factor for acquiring Hantavirus Pulmonary Syndrome. Deer mice are believed to enter buildings in order to gain access to a variety of resources including food, bedding material, and better thermal microclimates. However, no one has experimentally tested which factors influence mice use of buildings. We conducted experiments using small simulated buildings to determine the effects of two factors, i.e., food and bedding material, on mouse activity in these buildings. We also examined if these effects varied with time of year. We found that deer mice entered our buildings regardless of the presence or absence of food or bedding. However, the amount of activity in buildings was affected by what they contained. We found significantly higher indices of activity in buildings containing food compared to both empty buildings (control) and buildings containing bedding material. Time of year did not affect activity in buildings.

Presence of Rhodnius ecuadoriensis in sylvatic habitats in the southern highlands (Loja Province) of Ecuador.

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Grijalva, M J; Villacis, A G

2009-05-01

The main vectors of Chagas disease in Ecuador are Triatoma dimidiata and Rhodnius ecuadoriensis. The latter species occupies domestic and peridomestic habitats, as well as sylvatic ecotopes--particularly associated with Phytelephas aequatorialis palm trees--in the western coastal region of Ecuador. In the southern highlands, however, such palm tree habitats are uncommon, and sylvatic populations of R. ecuadoriensis have not previously been reported to date. This study was carried out in five rural communities in Loja Province in southern Ecuador, where manual triatomine searches were conducted in various sylvatic habitats. A total of 81 squirrel nests (Sciurus stramineus) and > 200 bird nests and other habitats were searched. One hundred three R. ecuadoriensis individuals were found in 11 squirrel nests (infestation index = 13.6%, density = 2 bugs per nest searched, crowding = 9.5 bugs per infested nest, colonization index = 72.7% of infested nests with nymphs). No triatomines were found in bird nests or other sylvatic habitats. The presence of sylvatic R. ecuadoriensis in the southern highlands of Ecuador has important implications for the long-term control of Chagas disease in the region because of the possibility of reinfestation of dwellings after insecticide-based control interventions.

Evaluation of Leishmania (Leishmania chagasi strains isolated from dogs originating from two visceral leishmaniasis-endemic areas in Brazil using multilocus enzyme electrophoresis

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Carlos Eduardo Ribeiro Coutinho

2011-10-01

Full Text Available INTRODUCTION: Domestic dogs are the most important reservoir in the peridomestic transmission cycle of Leishmania (Leishmania chagasi. The genetic variability of subpopulations of this parasite circulating in dogs has not been thoroughly analyzed in Brazil, even though this knowledge has important implications in the clinical-epidemiological context. METHODS: The objective of this study was to evaluate and compare the phenotypic variability of 153 L. chagasi strains isolated from dogs originating from the municipalities of Rio de Janeiro (n = 57 and Belo Horizonte (n = 96, where the disease is endemic. Strains isolated only from intact skin were selected and analyzed by multilocus enzyme electrophoresis using nine enzyme systems (6PG, GPI, NH1 and NH2, G6P, PGM, MDH, ME, and IDHNADP. RESULTS: The electrophoretic profile was identical for all isolates analyzed and was the same as that of the L. chagasi reference strain (MHOM/BR/74/PP75. Phenetic analysis showed a similarity index of one for all strains, with the isolates sharing 100% of the characteristics analyzed. CONCLUSIONS: The results demonstrate that the L. chagasi populations circulating in dogs from Rio de Janeiro and Belo Horizonte belong to a single zymodeme.

Indoor-breeding of Aedes albopictus in northern peninsular Malaysia and its potential epidemiological implications.

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Hamady Dieng

Full Text Available BACKGROUND: The mosquito Ae. albopictus is usually adapted to the peri-domestic environment and typically breeds outdoors. However, we observed its larvae in most containers within homes in northern peninsular Malaysia. To anticipate the epidemiological implications of this indoor-breeding, we assessed some fitness traits affecting vectorial capacity during colonization process. Specifically, we examined whether Ae. albopictus exhibits increased survival, gonotrophic activity and fecundity due to the potential increase in blood feeding opportunities. METHODOLOGY/PRINCIPAL FINDINGS: In a series of experiments involving outdoors and indoors breeding populations, we found that Ae. albopictus lives longer in the indoor environment. We also observed increased nighttime biting activity and lifetime fecundity in indoor/domestic adapted females, although they were similar to recently colonized females in body size. CONCLUSION/SIGNIFICANCE: Taken together these data suggest that accommodation of Ae. albopictus to indoor/domestic environment may increase its lifespan, blood feeding success, nuisance and thus vectorial capacity (both in terms of increased vector-host contacts and vector population density. These changes in the breeding behavior of Ae. albopictus, a potential vector of several human pathogens including dengue viruses, require special attention.

The sandfly fauna (Diptera: Psychodidae: Phlebotominae of the Parque Estadual da Serra da Tiririca, Rio de Janeiro, Brazil

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Andressa Alencastre Fuzari Rodrigues

2013-11-01

Full Text Available Cutaneous leishmaniasis (CL in the state of Rio de Janeiro is sporadic and can be characterised as a peridomestic transmission that occurs in modified natural environments. The aim of this work was to study the fauna and ecological characteristics of sandflies in an environmentally protected area (the State Park of Serra da Tiririca within the remnants of the Atlantic Forest in the municipalities of Niterói and Maricá and their possible relationship with leishmaniasis. Captures were performed using light traps during the night once a month for one year in both sylvatic environments and areas surrounding homes near the park. A total of 1,037 sandflies were captured, belonging to nine genera and 12 species: Evandromyia tupynambai (34.1%, Migonemyia migonei (20.6%, Brumptomyia cunhai (13.8%, Micropygomyia schreiberi (9.7%, Psathyromyia lanei (6.5%, Brumptomyia nitzulescui (5.7%, Evandromyia edwardsi (5.4%, Nyssomyia intermedia (2.8%, Evandromyia cortelezzii (0.6%, Pintomyia bianchigalatiae (0.5%, Lutzomyia longipalpis (0.2% and Sciopemyia microps (0.1%. Both Mg. migonei and Ny. intermedia may be acting as vectors of CL in this area.

Assessing the mitochondrial DNA diversity of the Chagas disease vector Triatoma sordida (Hemiptera: Reduviidae

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Grasielle Caldas D‘Ávila Pessoa

2016-01-01

Full Text Available Triatoma sordida is a species that transmits Trypanosoma cruzi to humans. In Brazil, T. sordida currently deserves special attention because of its wide distribution, tendency to invade domestic environments and vectorial competence. For the planning and execution of control protocols to be effective against Triatominae, they must consider its population structure. In this context, this study aimed to characterise the genetic variability of T. sordida populations collected in areas with persistent infestations from Minas Gerais, Brazil. Levels of genetic variation and population structure were determined in peridomestic T. sordida by sequencing a polymorphic region of the mitochondrial cytochrome b gene. Low nucleotide and haplotype diversity were observed for all 14 sampled areas; π values ranged from 0.002-0.006. Most obtained haplotypes occurred at low frequencies, and some were exclusive to only one of the studied populations. Interpopulation genetic diversity analysis revealed strong genetic structuring. Furthermore, the genetic variability of Brazilian populations is small compared to that of Argentinean and Bolivian specimens. The possible factors related to the reduced genetic variability and strong genetic structuring obtained for studied populations are discussed in this paper.

Study on phlebotomine sand fly (Diptera: Psychodidae fauna in Belo Horizonte, state of Minas Gerais, Brazil

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Carina Margonari de Souza

2004-12-01

Full Text Available A study on the phlebotomine sand fly fauna in Belo Horizonte city, state of Minas Gerais, Brazil, was carried out. From April 2001 to March 2003, monthly systematic collections were performed in three houses from each of the nine regions of the city, using CDC light traps for four consecutive days. The traps were set into the houses and in peridomestic areas totaling 54 traps. A number of 3871 sand fly specimens of the genera Lutzomyia and Brumptomyia were collected. Sixty eight percent of the specimens were L. longipalpis and 16% L. whitmani, insect vectors of visceral and American cutaneous leishmaniasis, respectively. Environmental factors such as temperature, humidity, and frequency of precipitation suggest that the number of insects increases after rainy periods. During the same period mentioned above, seasonal captures were carried out in parks and green areas of Belo Horizonte, using Shannon trap. A total of 579 phlebotomine sand flies were collected from which 398 (68.7% were females with the predominance of L. whitmani and L. monticola. Those specimens were used for natural infection examination, by polymerase chain reaction. No Leishmania DNA was present in any of the specimens tested.

Rickettsial Disease in the Peruvian Amazon Basin.

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Kocher, Claudine; Morrison, Amy C; Leguia, Mariana; Loyola, Steev; Castillo, Roger M; Galvez, Hugo A; Astete, Helvio; Flores-Mendoza, Carmen; Ampuero, Julia S; Bausch, Daniel G; Halsey, Eric S; Cespedes, Manuel; Zevallos, Karine; Jiang, Ju; Richards, Allen L

2016-07-01

Using a large, passive, clinic-based surveillance program in Iquitos, Peru, we characterized the prevalence of rickettsial infections among undifferentiated febrile cases and obtained evidence of pathogen transmission in potential domestic reservoir contacts and their ectoparasites. Blood specimens from humans and animals were assayed for spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) by ELISA and/or PCR; ectoparasites were screened by PCR. Logistic regression was used to determine associations between patient history, demographic characteristics of participants and symptoms, clinical findings and outcome of rickettsial infection. Of the 2,054 enrolled participants, almost 2% showed evidence of seroconversion or a 4-fold rise in antibody titers specific for rickettsiae between acute and convalescent blood samples. Of 190 fleas (Ctenocephalides felis) and 60 ticks (Rhipicephalus sanguineus) tested, 185 (97.4%) and 3 (5%), respectively, were positive for Rickettsia spp. Candidatus Rickettsia asemboensis was identified in 100% and 33% of the fleas and ticks tested, respectively. Collectively, our serologic data indicates that human pathogenic SFGR are present in the Peruvian Amazon and pose a significant risk of infection to individuals exposed to wild, domestic and peri-domestic animals and their ectoparasites.

Allometria da palmeira babaçu em um agroecossistema de derruba-e-queima na periferia este da Amazônia Allometry of the babassu palm growing on a slash-and-burn agroecosystem of the eastern periphery of Amazonia

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Christoph Gehring

2011-03-01

Full Text Available A palmeira babaçu (Attalea speciosa C.Martius, Arecaceae tem grande importância socioeconômica e ecológica em grande parte da área tropical brasileira, especialmente em áreas degradadas por queimadas freqüentes na Amazônia. No entanto, ainda pouco se sabe sobre as características ecológicas desta espécie-chave. Este estudo investiga a alometria do babaçu com o objetivo de estabelecer uma metodologia eficiente na estimativa da biomassa aérea de palmeiras juvenis e adultas e para um melhor entendimento da sua arquitetura. A biomassa de palmeiras juvenis pode ser estimada facilmente e com precisão com o diâmetro mínimo das ráquis das folhas a 30 cm de extensão. A biomassa de palmeiras adultas pode ser estimada com base na altura do tronco lenhoso, também relativamente de fácil medição em campo. A biomassa foliar das palmeiras adultas foi em media 31,7% da biomassa aérea, porém houve uma alta variação e, portanto, somente pode ser estimada indiretamente através da relação entre a razão madeira:folha e biomassa aérea total. Os teores de carbono no babaçu apresentaram baixa variação, sem diferenças sistemáticas em relação ao tamanho ou estágio de crescimento, o que aponta à aplicabilidade geral dos valores 42.5% C para troncos, 39.8% C para folhas. Em conseqüência do limitado crescimento secundário do diâmetro inerente de palmeiras, não houve relação do diâmetro de tronco com a altura e a biomassa das palmeiras adultas. Observou-se que o afilamento do caule diminui com o aumento da altura das palmeiras, o que é parcialmente compensado pelo incremento da densidade de madeira em troncos quase-cilíndricos. No entanto, a altura máxima do babaçu, de cerca de 30 metros, aparentemente está definida por limitações na estabilidade mecânica. Todas as relações alométricas aqui descritas são independentes da idade da vegetação, indicando a aplicabilidade geral das relações encontradas

USOS DE LAS PALMAS EN LA AMAZONIA COLOMBIANA

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LAURA MESA

2013-12-01

Full Text Available Con el fin de obtener un diagnóstico del estado actual de conocimiento sobre usos de las palmas en la Amazonia colombiana, se revisaron las principales fuentes de información. Treinta y seis de las 41 etnias indígenas consideradas tuvieron registros de uso. Se registraron 82 especies de palmas usadas (78% de las potenciales y 165 usos distribuidos en ocho categorías; todos los usos se presentan de manera detallada en un catálogo. Las categorías de uso más importantes fueron: utensilios y herramientas, construcción, y alimentación humana. Las diez especies más importantes fueron Bactris gasipaes, Euterpe precatoria, Mauritia flexuosa, Oenocarpus bataua, Attalea maripa, Oenocarpus minor, Astrocaryum chambira, Iriartea deltoidea, Oenocarpus bacaba y Socratea exorrhiza; la mayoría de ellas también han sido registradas como las más importantes en otras partes del Neotrópico. No se encontró ninguna información sobre usos de palmas para varios grupos indígenas, especialmente para las etnias cocama, letuama, piaroa, pisamira y yurí, para las cuales se requieren investigaciones detalladas. Se concluye que a pesar de los vacíos de información, los resultados muestran que las palmas son un recurso muy importante con un gran potencial, y una pieza fundamental para la seguridad alimentaria y el desarrollo sustentable de la Amazonia colombiana. Sugerimos la inclusión de las especies más importantes en programas de manejo y agroforestales, al igual que la implementación y popularización de técnicas de cosecha no destructivas. Recomendamos además que las investigaciones futuras estén enfocadas en desarrollar estrategias de manejo que garanticen el uso sostenible de todas estas especies útiles.

Presumptive risk factors for monkeypox in rural communities in the Democratic Republic of the Congo.

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Claire A Quiner

Full Text Available Monkeypox virus (MPXV, a close relative of Variola virus, is a zoonotic virus with an unknown reservoir. Interaction with infected wildlife, bites from peri-domestic animals, and bushmeat hunting are hypothesized routes of infection from wildlife to humans. Using a Risk Questionnaire, performed in monkeypox-affected areas of rural Democratic Republic of the Congo, we describe the lifestyles and demographics associated with presumptive risk factors for MPXV infection. We generated two indices to assess risk: Household Materials Index (HMI, a proxy for socioeconomic status of households and Risk Activity Index (RAI, which describes presumptive risk for animal-to-human transmission of MPXV. Based on participant self-reported activity patterns, we found that people in this population are more likely to visit the forest than a market to fulfill material needs, and that the reported occupation is limited in describing behavior of individuals may participate. Being bitten by rodents in the home was commonly reported, and this was significantly associated with a low HMI. The highest scoring RAI sub-groups were 'hunters' and males aged ≥ 18 years; however, several activities involving MPXV-implicated animals were distributed across all sub-groups. The current analysis may be useful in identifying at-risk groups and help to direct education, outreach and prevention efforts more efficiently.

Entomological and epidemiological study of a new focus of cutaneous leishmaniasis in Morocco.

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Ramaoui, K; Guernaoui, S; Boumezzough, A

2008-09-01

Cutaneous leishmaniasis (CL) due to Leishmania tropica Wright has become an increasingly important problem in Al-Haouz province, Morocco. The objective of this paper was to undertake a retrospective analysis of CL between 2000 and 2006 and to study the sandfly fauna for the first time in this focus. The consultation of bulletins, registers and monthly and annual reports published by local and national medical services permitted a global synthesis of CL in Al-Haouz between 2000 and 2006. Sandflies were collected using sticky-paper traps in five selected stations in two communes, Ourika and Sti Fadma, the most affected by CL in Al-Haouz. Overall, 2,648 sandflies, belonging to five species of Phlebotomus and three of Sergentomyia, were collected. Phlebotomus sergenti Parrot (14.5%) was found in all studied stations where it was associated with domestic and peridomestic habitats. Based on this first report on ecology of sandflies and epidemiology of CL, Al-Haouz seems to be a typical focus of L. tropica and P. sergenti like the other Moroccan foci. Two communes, Sti Fadma and Ourika, constituted an important CL micro-focus in this region. Considering their economical importance (trade and tourism), they contribute probably to the dissemination of Leishmania parasite in bordering regions.

Geographic distribution and morphometric differentiation of Triatoma nitida usinger 1939 (Hemiptera: Reduviidae: Triatominae in Guatemala

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Monroy Carlota

2003-01-01

Full Text Available Triatoma nitida was found in 14 (0.4% out of 3,726 houses located in six departments across Guatemala, which were surveyed from 1994 to 1998 by the man-hour collection method. Compared to previous information, the distribution of T. nitida in Guatemala has increased from five to nine departments; the species is present in mild climates at altitudes from 960 to 1,500 m. Fourteen percent of the intradomestic T. nitida were infected with Trypanosoma cruzi. The species was often found in conjunction with other triatomines (T. dimidiata and Rhodnius prolixus. The domestic and peridomestic presence of T. nitida in Guatemala was rare, but occasionally this species was colonizing human-made constructions. T. nitida appears to have a low importance as Chagas disease vector in Guatemala, as indicated by its scarce presence in the domestic habitats and defecation patterns. However, it clearly has potential to become a Chagas vector so we recommend an on-going study of the intradomestic presence of T. nitida following the control programs in Guatemala. Morphometric analysis of 47 T. nitida males from three localities showed quantitative differences between the populations, which indicates that geographic distance is an important factor in the structuring of T. nitida populations.

Patterns of sugar feeding and host plant preferences in adult males of An. gambiae (Diptera: Culicidae).

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Gouagna, Louis-Clément; Poueme, Rodrigue S; Dabiré, Kounbobr Roch; Ouédraogo, Jean-Bosco; Fontenille, Didier; Simard, Frédéric

2010-12-01

Sugar feeding by male mosquitoes is critical for their success in mating competition. However, the facets of sugar source finding under natural conditions remain unknown. Here, evidence obtained in Western Burkina Faso indicated that the distribution of An. gambiae s.s. (M and S molecular forms) males across different peri-domestic habitats is dependent on the availability of potential sugar sources from which they obtain more favorable sites for feeding or resting. Among field-collected anophelines, a higher proportion of specimens containing fructose were found on flowering Mangifera indica (Anacardiaceae), Dolonix regia (Fabaceae), Thevetia neriifolia (Apocynaceae), Senna siamea, and Cassia sieberiana (both Fabaceae) compared to that recorded on other nearby plants, suggesting that some plants are favored for use as a sugar source over others. Y-tube olfactometer assays with newly-emerged An. gambiae s.s. exposed to odors from individual plants and some combinations thereof showed that males use odor cues to guide their preference. The number of sugar-positive males was variable in a no-choice cage assay, consistent with the olfactory response patterns towards corresponding odor stimuli. These experiments provide the first evidence both in field and laboratory conditions for previously unstudied interactions between males of An. gambiae and natural sugar sources. © 2010 The Society for Vector Ecology.

Habitats of the sandfly vectors of Leishmania tropica and L. major in a mixed focus of cutaneous leishmaniasis in southeast Tunisia.

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Tabbabi, Ahmed; Ghrab, Jamila; Aoun, Karim; Ready, Paul Donald; Bouratbine, Aïda

2011-08-01

From 2009 to 2010, 3129 sandflies were caught in CDC light traps placed in various habitats in Ghomrassen, Tataouine governorate, southeast Tunisia, a mixed focus of human cutaneous leishmaniasis caused by Leishmania tropica and Leishmania major. Species diversity was quantified in anthropogenic, semi-anthropogenic and semi-natural locations. Sandflies were identified according to morphological characters and also by the comparative sequence analysis of a fragment of the mitochondrial cytochrome b gene to distinguish between two putative local vectors of L. tropica, namely Phlebotomus chabaudi and Phlebotomus riouxi. The lowest sandfly diversities were found in L. major sites, where the incriminated vector P. papatasi predominated in the burrows of the rodent reservoir hosts (Meriones) as well as inside and outside houses of human cases. In L. tropica sites, the incriminated peri-domestic vector Phlebotomus sergenti was the most abundant species inside houses, whereas P. riouxi or P. chabaudi was the dominant species in the semi-natural rocky habitats favoured by the putative rodent reservoir, Ctenodactylus gundi. All specimens of P. chabaudi identified molecularly had the diagnostic cytochrome b characters of P. riouxi, indicating either that the latter represents only a geographical variant of P. chabaudi or that these two species may sometimes hybridize. Copyright © 2011 Elsevier B.V. All rights reserved.

The Triatomines of Northern Peru, with Emphasis on the Ecology and Infection by Trypanosomes of Rhodnius ecuadoriensis (Triatominae

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Cuba Cuba César A

2002-01-01

Full Text Available Information on the distribution and synanthropic behaviour of triatomines is essential for Chagas disease vector control. This work summarises such information from northern Peru, and presents new data on Rhodnius ecuadoriensis - an important local vector infesting 10-35% of dwellings in some zones. Three species are strongly synanthropic and may be suitable targets for chemical control of domestic/peridomestic bug populations. Panstrongylus herreri, the main domestic vector in the area, is probably present in sylvatic ecotopes in the Marañón river system. R. ecuadoriensis and Triatoma dimidiata seem exclusively domestic; biogeographical and ecological data suggest they might have spread in association with humans in northern Peru. Confirmation of this hypothesis would result in a local eradication strategy being recommended. Presence of trypanosome natural infection was assessed in 257 R. ecuadoriensis; Trypanosoma rangeli was detected in 4% of bugs. Six further triatomine species are potential disease vectors in the region (T. carrioni, P. chinai, P. rufotuberculatus, P. geniculatus, R. pictipes, and R. robustus, whilst Eratyrus mucronatus, E. cuspidatus, Cavernicola pilosa, Hermanlentia matsunoi, and Belminus peruvianus have little or no epidemiological significance. A strong community-based entomological surveillance system and collaboration with Ecuadorian public health authorities and researchers are recommended.

Occurrence of Lutzomyia longipalpis (Phlebotominae) and canine visceral leishmaniasis in a rural area of Ilha Solteira, SP, Brazil.

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Spada, Julio Cesar Pereira; Silva, Diogo Tiago da; Martins, Kennya Rozy Real; Rodas, Lílian Aparecida Colebrusco; Alves, Maria Luana; Faria, Glaucia Amorim; Buzutti, Marcelo Costa; Silva, Hélio Ricardo; Starke-Buzetti, Wilma Aparecida

2014-01-01

This study aimed to investigate the occurrence of Lutzomyia longipalpis and also the canine visceral leishmaniasis (CVL) in a rural area of Ilha Solteira, state of São Paulo. Blood samples were collected from 32 dogs from different rural properties (small farms) and were analyzed by ELISA and the indirect immunofluorescence antibody test (IFAT) in order to diagnose CVL. From these serological tests, 31.25% of the dogs were positive for CVL and these were distributed in 66.7% (8/12) of the rural properties, which were positive for L. longipalpis. CDC (Center for Disease Control and Prevention) light traps were installed in 12 properties (one per property) and insects were caught on three consecutive days per month for one year. L. longipalpis was present on 100% of the rural properties visited, at least once during the twelve-month interval, totaling 64 males and 25 females. The insects were more numerous after the peak of the rain, but the association between prevalence of peridomestic vectors and the climatic data (precipitation, relative air humidity and temperature) and the occurrences of CVL among dogs on each rural property were not statistical significant (p longipalpis indicate that more attention is necessairy for the control of this disease in the rural area studied.

Effectiveness of dog collars impregnated with 4% deltamethrin in controlling visceral leishmaniasis in Lutzomyia longipalpis (Diptera: Psychodidade: Phlebotominae) populations.

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Silva, Rafaella Albuquerque E; Andrade, Andrey José de; Quint, Bruno Beust; Raffoul, Gabriel Elias Salmen; Werneck, Guilherme Loureiro; Rangel, Elizabeth Ferreira; Romero, Gustavo Adolfo Sierra

2018-03-26

There is little information on the effect of using deltamethrin-impregnated dog collars for the control of canine visceral leishmaniasis. The objective of this study was to evaluate the effectiveness of the use of 4% deltamethrin-impregnated collars (Scalibor®) in controlling visceral leishmaniasis in Lutzomyia longipalpis by comparing populations in intervention and non-intervention areas. Phlebotomine flies were captured over 30 months in four neighbourhoods with intense visceral leishmaniasis transmission in Fortaleza and Montes Claros. We calculated the rates of domicile infestation, relative abundance of Lu. longipalpis, and Lu. longipalpis distribution in each site, capture location (intra- and peridomestic locations) and area (intervention and non-intervention areas). In the control area in Fortaleza, the relative abundance of Lu. longipalpis was 415 specimens at each capture site, whereas in the intervention area it was 159.25; in Montes Claros, the relative abundance was 5,660 specimens per capture site in the control area, whereas in the intervention area it was 2,499.4. The use of dog collars was associated with a reduction in captured insects of 15% (p = 0.004) and 60% (p < 0.001) in Montes Claros and Fortaleza, respectively. We observed a lower vector abundance in the intervention areas, suggesting an effect of the insecticide-impregnated collars.

Leishmania (Viannia) braziliensis infection in two Colombian dogs: a note on infectivity for sand flies and response to treatment.

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Travi, Bruno L; Tabares, Carlos Javier; Cadena, Horacio

2006-10-01

Although canine cutaneous leishmaniasis has been reported in several foci of South America, no published information from Colombia is available. We report on two cases found in the Pacific coast region of this country, which presented as a single scrotal ulcer in one dog, and two ulcers on the external surface of the ear in a second dog. Parasites were isolated by culture in Senekjie's culture medium and identified using monoclonal antibodies. The capacity of these dogs to transmit the parasites to sand fly vectors (Lutzomyia trapidoi, Lutzomyia gomezi, Lutzomyia longipalpis, Lutzomyia youngi) was tested by allowing the flies to feed on the lesion borders. Both isolates were identified as Leishmania (Viannia) braziliensis. No infections were detected upon dissection of engorged flies. A single peri-and sub-lesional injection of 1-2 ml of pentavalent antimony in the dog with ear lesions resulted in clinical cure 6 weeks post-treatment. These observations suggest that although dogs are susceptible to L. braziliensis, their reservoir competence could be low. However, if further studies indicate that canines are capable reservoir hosts of L. Viannia spp., the local treatment of lesions could become a feasible approach to diminish the risk of human infection in the peridomestic setting, without sacrificing infected dogs.

USO DE NANOPARTÍCULAS DO MESOCARPO DO BABAÇU COMO PLATAFORMA PARA ANCORAGEM DE ENZIMAS NO DESENVOLVIMENTO DE BIOSSENSORES: UM MAPEAMENTO TECNOLÓGICO

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Ana Siqueira do Nascimento Marreiro Teixeira

2018-03-01

Full Text Available A imobilização de enzimas na construção de biossensores torna-se atraente pela capacidade enzimática de catalisar com grande eficiência, reações biológicas com alta sensibilidade e seletividade. A utilização de materiais nanoestruturados, tais como nanopartículas poliméricas, surge como alternativa para aumentar a eficiência da imobilização de enzimas. Dessa forma, surge o interesse na síntese de nanopartículas do mesocarpo do babaçu (Orbignya phalerata Mart, por se tratar de um biopolímero natural, atóxico, facilmente encontrado na região nordeste do País. Diante do relatado, o presente trabalho propõe um estudo prospectivo a respeito do desenvolvimento de um biossensor contendo a enzima polifenol oxidase como monocamada imobilizada, pela técnica de automontagem, sobre a superfície de nanoparticulas poliméricas geradas a partir do mesocarpo de babaçu para detecção de sulfitos em produtos alimentícios, visto que tais compostos são causadores de reações alérgicas em indivíduos que apresentam sensibilidade a este conservante. Para o mapeamento científico e tecnológico, foram realizadas buscas nas bases de periódicos Web of Science, Scopus e Scielo, e nos bancos de patentes INPI, Espacenet e USPTO, para todas patentes depositadas, e artigos publicados no período de 2005 a agosto 2016. A partir dos artigos e patentes analisados, constatou-se que os estudos relacionados ao mesocarpo de babaçu são escassos, sendo que o desenvolvimento de um biossensor para detecção de sulfito a base de nanopartículas poliméricas deste biopolímero como plataforma para a imobilização da enzima polifenol oxidase para pode ser bastante inovador, visto que não foram encontrados relatos na literatura com abordagem parecida.

Infestación domiciliaria por triatominos y seroprevalencia humana en el Departamento Empedrado, Corrientes, Argentina Household infestation by triatomines and human seroprevalence in Empedrado Department, Corrientes, Argentina

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Maria Esther Bar

1997-04-01

Full Text Available En el presente estudio se investigó la colonización domiciliaria y peridomiciliaria por triatominos, el índice de infección de Triatoma infestans y la presencia de seropositivos humanos al Trypanosoma cruzi, en áreas rurales del Departamento Empedrado, Corrientes, Argentina. La metodología utilizada en la búsqueda, determinación sistemática, obtención de índices de infección de los triatominos y en ta detección de seropositivos fue mencionada en un trabajo previo. El 53,0% de las 100 viviendas estudiadas tenían paredes de "chorizo", el 37,5% de los techos eran de chapas de zinc o cartón, combinadas con otros materiales y el 83,0% tenta pisos de tierra. En el 91,0% de los domicílios los pobladores cohabitaban con animales domésticos. La infestación domiciliaria por triatominos fue del 30,0%, correspondiendo 29,0% a T. infestans y 1,0% a Triatoma sordida. El índice de infección natural de T. infestans por T. cruzi fue 23, el índice de colanizacián fue 75 y el de dispersián alcanzá a 54,5. El 12, 1 % de los peridomicilios estaban infestados por T. sordida y el 2,4% por T. infestans. La prevalencia general de los 298 pacientes analizados, por los tests de Hemaglutinacián Indirecta e Inmunofluorescencia Indirecta, fue del 32,2%, destacándose el alto porcentaje de infectados (23,7%, hallado en el grupo etario de 0-10 años, que representa al de mayor riesgo de transmisión.Domestic and peridomestic triatomine colonization, T. infestans infection rate and human seropositives to Trypanosoma cruzi in rural areas of Empedrado Department, Corrientes, Argentina, were carried out. Methods used in order to search the triatomines, to determine them systematically, to obtain their infection rates and the human seropositives, were the same applied in a previous report. From 100 households characterized, 53.0% had mud walls, laminated zinc or cardboard combined with other elements were used in 37.5% of the roofs, and 83.0% had earthen

Feeding sources and trypanosome infection index of Rhodnius pallescens in a Chagas disease endemic area of Amador County, Panama Fontes de alimentação de R. pallescens e índice de infecção por Trypanosoma em área endêmica da doença de Chagas em Amador, região central do Panamá

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Vanessa Pineda

2008-04-01

Full Text Available The sylvatic triatomine Rhodnius pallescens is considered to be the most important and widespread vector of Trypanosoma cruzi and Trypanosoma rangeli in Panama. However, its behavior and biological characteristics have only been partially investigated. Thus, to achieve sustainable and efficient control over Chagas disease in Panama, a better understanding of the ecology and biology of R. pallescens is essential. In this study we evaluated R. pallescens host feeding sources using a dot-blot assay, and the trypanosome infection index by PCR analysis in a Chagas disease endemic area of central Panama. It was found that in peridomestic palm trees, 20.3% of the examined bugs had fed on opossums (Didelphis marsupialis. However, we observed an increased anthropophagy (25.4% for those bugs collected inside houses. Considering the domestic and peridomestic habitats as a whole, the proportion of collected R. pallescens infected with trypanosomes was 87.4%. In the two habitats the predominant infection was with T. cruzi (80-90%. Between 47-51% of the analyzed triatomines were infected with T. rangeli. Mixed infections (40-51% were also detected. These findings provide a better basis for the implementation of a rational control and surveillance program for Chagas disease in regions where R. pallescens is endemic.O triatomíneo silvestre Rhodnius pallescens é considerado o mais importante vetor do Trypanosoma cruzi e Trypanosoma rangeli no Panamá. Entretanto, seu comportamento e características biológicas são pouco estudados. Para controlar a doença de Chagas no Panamá é necessário melhorar a compreensão dos aspectos eco-biológicos do R. pallescens. Neste estudo, investigaram-se as fontes de alimentação de R. pallescens usando dot-blot e o índice de infecção por Trypanosoma por metodologia molecular, em área endêmica da doença de Chagas na região central do Panamá. Foi observado que 20,3% dos barbeiros coletados em palmeiras peridom

Household-level and surrounding peri-domestic environmental characteristics associated with malaria vectors Anopheles arabiensis and Anopheles funestus along an urban-rural continuum in Blantyre, Malawi.

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Dear, Nicole F; Kadangwe, Chifundo; Mzilahowa, Themba; Bauleni, Andy; Mathanga, Don P; Duster, Chifundo; Walker, Edward D; Wilson, Mark L

2018-06-08

Malaria is increasing in some recently urbanized areas that historically were considered lower risk. Understanding what drives urban transmission is hampered by inconsistencies in how "urban" contexts are defined. A dichotomized "urban-rural" approach, based on political boundaries may misclassify environments or fail to capture local drivers of risk. Small-scale agriculture in urban or peri-urban settings has been shown to be a major risk determinant. Household-level Anopheles abundance patterns in and around Malawi's commercial capital of Blantyre (~ 1.9 M pop.) were analysed. Clusters (N = 64) of five houses each located at 2.5 km intervals along eight transects radiating out from Blantyre city centre were sampled during rainy and dry seasons of 2015 and 2016. Mosquito densities were measured inside houses using aspirators to sample resting mosquitoes, and un-baited CDC light traps to sample host seeking mosquitoes. Of 38,895 mosquitoes captured, 91% were female and 87% were Culex spp. Anopheles females (N = 5058) were primarily captured in light traps (97%). Anopheles abundance was greater during rainy seasons. Anopheles funestus was more abundant than Anopheles arabiensis, but both were found on all transects, and had similar associations with environmental risk factors. Anopheles funestus and An. arabiensis females significantly increased with distance from the urban centre, but this trend was not consistent across all transects. Presence of small-scale agriculture was predictive of greater Anopheles spp. abundance, even after controlling for urbanicity, number of nets per person, number of under-5-year olds, years of education, and season. This study revealed how small-scale agriculture along a rural-to-urban transition was associated with An. arabiensis and An. funestus indoor abundances, and that indoor Anopheles density can be high within Blantyre city limits, particularly where agriculture is present. Typical rural areas with lower house density and greater distance from urban centres reflected landscapes more suitable for Anopheles reproduction and house invasion. However, similar characteristics and elevated Anopheles abundances were also found around some houses within the city limits. Thus, dichotomous designations of "urban" or "rural" can obscure important heterogeneity in the landscape of Plasmodium transmission, suggesting the need for more nuanced assessment of urban malaria risk and prevention efforts.

Infectious diseases in Mexico. A survey from 1995-2000.

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Flisser, Ana; Velasco-Villa, Andrés; Martínez-Campos, Carmen; González-Domínguez, Fernando; Briseño-García, Baltasar; García-Suárez, Rosario; Caballero-Servín, Angel; Hernández-Monroy, Irma; García-Lozano, Herlinda; Gutiérrez-Cogco, Lucina; Rodríguez-Angeles, Guadalupe; López-Martínez, Irma; Galindo-Virgen, Sonia; Vázquez-Campuzano, Roberto; Balandrano-Campos, Susana; Guzmán-Bracho, Carmen; Olivo-Díaz, Angélica; de la Rosa, Jorge; Magos, Clementina; Escobar-Gutiérrez, Alejandro; Correa, Dolores

2002-01-01

Data obtained at a central laboratory for emerging, re-emerging, and other infectious diseases in Mexico from 1995-2000 are presented. An outstanding increase of DEN-3 circulation was identified. Aedes aegypti, the dengue vector, is widely distributed. Leptospirosis has become the most important differential diagnosis for dengue. Identification of rabies virus variants allowed cataloging of new transmitters of rabies. Rotavirus showed a clear seasonal distribution, while different proportions of pathogenic classes of Escherichia coli under endemic and outbreak conditions were seen. Serotypes of several bacteria are reported as well as the sources of isolation and frequency of Shigella, Salmonella, and Vibrio cholerae. Rise and disappearance of cholera could be followed along the past decade. Influenza strains were identified, as were several pathogens causing sexually transmitted infections. Laboratory support was important for surveillance after Hurricane Mitch. Multidrug-resistant strains of Mycobacterium tuberculosis are emerging and primary resistance is very high. It is now mandatory to search for antibodies to Trypanosoma cruzi in blood banks. Triatoma barberi, a peridomestic bug, is the main vector of Chagas disease. Localized cutaneous leishmaniosis increased in regions having a guerrilla element in Chiapas. Modern immunodiagnostic techniques are used for control studies of cysticercosis and similar techniques were recently standardized for Trichinella spiralis detection. Low iodine values in children's urine were found in several Mexican states; therefore, use of iodized salt should be encouraged.

Epidemiological factors related to the transmission risk of Trypanosoma cruzi in a Quilombola community, State of Mato Grosso do Sul, Brazil

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Marlon Cezar Cominetti

2011-10-01

Full Text Available INTRODUCTION: This work was an epidemiological investigation of the risk of Trypanosoma cruzi transmission in the rural Quilombola community of Furnas do Dionízio, State of Mato Grosso do Sul, Brazil. METHODS: Of the 71 animals examined, seven were captured (two opossums, Didelphis albiventris; four rats, Rattus rattus; and one nine-banded armadillo, Dasypus novemcinctus and 64 were domestic (one canine, Canis familiaris; five pigs, Sus scrofa; two bovines, Bos taurus; five caprines, Capra sp.; and 51 ovines, Ovis aries. Parasitological tests were performed to detect parasites in the blood and to identify the morphology of flagellates. These methods included fresh examinations, buffy coat tests and blood cultures. Molecular analysis of DNA for identification of trypanosomatids was performed by polymerase chain reaction (PCR with primers S35 and S36. RESULTS: The parasitological tests showed flagellates in an opossum and two cattle. The molecular tests showed DNA from T. cruzi in an opossum and a pig. Triatoma sordida was the only triatomine species found in the community, and it colonized households (four specimens and the surrounding areas (124 specimens. Twenty-three specimens tested positive for flagellates, which were subsequently identified as T. cruzi by PCR. CONCLUSIONS: Data analysis demonstrated that T. cruzi has a peridomestic life cycle that involves both domestic and wild mammals.

Changes related to gender, geographic population and habitat in the antennal phenotype of Triatoma patagonica Del Ponte, 1929 (Hemiptera: Reduviidae).

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Rodríguez, Claudia S; Crocco, Liliana; Altamirano, Alejandra; Catalá, Silvia

2013-02-01

Triatomines undergo morphological changes as an adaptive response to different habitats (wild, peridomestic, domestic, laboratory). The characterization of the antennal phenotype provides information on intraspecific variation caused by geographical origin and/or habitat. Triatoma patagonica Del Ponte, 1929 is known to occur in peridomiciles of rural areas in Argentina, where it also invades non-colonized dwellings. Here we describe and compare the antennal phenotype of T. patagonica in populations of different geographic origin, and explore possible modifications induced by laboratory rearing with the aim of investigating the range of phenotypic variation of the species for the first time. Sixty antennas of adult males and females of T. patagonica belonging to two peridomiciliary populations of different geographical origin were analyzed. Four types of sensilla were observed in three antennal segments, showing sexual dimorphism in the species. The multivariate analysis separated the populations of similar habitat (peridomicile) but different geographical origin, without showing differences between the peridomiciliary and laboratory populations of the same geographical origin. These results suggest phenotypic plasticity in T. patagonica, which would allow the species to adapt to a wide range of habitats without having a close association with a given host and its environment. The range of antennal phenotypic variation of T. patagonica would also be an indicator of its current stage of adaptation to the human environment. Copyright © 2012 Elsevier B.V. All rights reserved.

Leishmania (Viannia braziliensis infection in two Colombian dogs: a note on infectivity for sand flies and response to treatment

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Bruno L. Travi

2006-10-01

Full Text Available Introduction. Although canine cutaneous leishmaniasis has been reported in several foci of South America, no published information from Colombia is available. Objective. We report on two cases found in the Pacific coast region of this country, which presented as a single scrotal ulcer in one dog, and two ulcers on the external surface of the ear in a second dog. Materials and methods. Parasites were isolated by culture in Senekjie’s culture medium and identified using monoclonal antibodies. The capacity of these dogs to transmit the parasites to sand fly vectors (Lutzomyia trapidoi, Lutzomyia gomezi, Lutzomyia longipalpis, Lutzomyia youngi was tested by allowing the flies to feed on the lesion borders. Results. Both isolates were identified as Leishmania (Viannia braziliensis. No infections were detected upon dissection of engorged flies. A single peri-and sub-lesional injection of 1-2 ml of pentavalent antimony in the dog with ear lesions resulted in clinical cure 6 weeks post-treatment. Conclusions. These observations suggest that although dogs are susceptible to L. braziliensis, their reservoir competence could be low. However, if further studies indicate that canines are capable reservoir hosts of L. Viannia spp., the local treatment of lesions could become a feasible approach to diminish the risk of human infection in the peridomestic setting, without sacrificing infected dogs.

Diatomaceous earth and oil enhance effectiveness of Metarhizium anisopliae against Triatoma infestans.

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Luz, Christian; Rodrigues, Juscelino; Rocha, Luiz F N

2012-04-01

Entomopathogenic fungi, especially Metarhizium anisopliae, have potential for integrated control of peridomestic triatomine bugs. However, the high susceptibility of these vectors to fungal infection at elevated ambient humidities decreases in the comparatively dry conditions that often prevail in their microhabitats. A formulation adapted to this target pest that induces high and quick mortality can help to overcome these drawbacks. In the present study diatomaceous earth, which is used against pests of stored grains or as an additive to mycoinsecticides, delayed but did not reduce in vitro germination of M. anisopliae s.l. IP 46 conidia after >24h agitation without affecting viability, and did not hamper the survival of Triatoma infestans nymphs exposed to treated surfaces. The settling behavior of nymphs on a treated surface in choice tests depended on the concentration of diatomaceous earth and ambient light level. Conidia formulated with diatomaceous earth and a vegetable oil synergized the insecticidal effect of the fungus in nymphs, and quickly killed all treated insects, even at 75% relative humidity (LT(90) 8.3 days) where unformulated conidia caused only 25% mortality after a 25 days exposure. The improved performance of a combined oil and desiccant dust formulation of this Metarhizium isolate raises the likelihood for its successful mycoinsecticidal use for triatomine control and, apparently, against other domestic insect pests. Copyright © 2011 Elsevier B.V. All rights reserved.

Observations on the distribution of anophelines in Suriname with particular reference to the malaria vector Anopheles darlingi

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J. A. Rozendaal

1990-06-01

Full Text Available A study was made on the distribution of anophelines in Suriname with special emphasis on the principal malaria vector Anopheles darlingi and on the occurrence of other possible vector species. Peridomestic human bait collections of adult mosquitoes and collections of larvae were made in many localities with a recent history of malaria transmission. Stable population of An. darlingi were only found in the interior, south of the limit of tidal influence, due to year-round availability of breeding habitats in quietly sunlit places in flooded forest areas and along river banks. In the area with tidal movement of the rivers, breeding is limited to flooded areas in the west season. Anopheles darlingi was only incidentally collected in low densities. In the interior, malaria transmission occurred in all places where An. darlingi was found. The absence of malaria transmission along the Upper Suriname River could be explained by the absence of An. darlingi. In the malaria endemic areas, An darlingi was the most numerous mosquito biting on man. In the tidal region, malaria outbreak are infrequent and might be explained by the temporary availability of favourable beeding habitats for An. darlingi. However, evidence is insufficient to incriminate an. darlingi as the vector of malaria in this region and the possible vectorial role of other anophelines is discussed.

Prevalence of antibodies to canine parvovirus and distemper virus in wolves in the Canadian Rocky Mountains.

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Nelson, Brynn; Hebblewhite, Mark; Ezenwa, Vanessa; Shury, Todd; Merrill, Evelyn H; Paquet, Paul C; Schmiegelow, Fiona; Seip, Dale; Skinner, Geoff; Webb, Nathan

2012-01-01

Wild carnivores are often exposed to diseases via contact with peridomestic host species that travel through the wildland-urban interfaces. To determine the antibody prevalences and relationships to human activity for two common canid pathogens, we sampled 99 wolves (Canis lupus) from 2000 to 2008 for antibodies to canine parvovirus (CPV) and canine distemper virus (CDV) in Banff and Jasper National Parks and surrounding areas of the Canadian Rockies. This population was the source for wolves reintroduced into the Northern Rockies of the US. Of 99 wolves sampled, 94 had detectable antibody to CPV (95%), 24 were antibody-positive for CDV (24%), and 24 had antibodies to both pathogens (24%). We tested whether antibody prevalences for CPV and CDV were higher closer to human activity (roads, town sites, First Nation reserves) and as a function of sex and age class. Wolves ≥2 yr old were more likely to be have antibodies to CPV. For CDV, male wolves, wolves ≥2 yr, and those closer to First Nation reserves were more likely to have antibodies. Overall, however, we found minimal support for human influence on antibody prevalence for CDV and CPV. The similarity between our antibody prevalence results and results from recent studies in Yellowstone National Park suggests that at least in the case of CDV, and perhaps CPV, these could be important pathogens with potential effects on wolf populations.

Leptospira Contamination in Household and Environmental Water in Rural Communities in Southern Chile

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Claudia Muñoz-Zanzi

2014-06-01

Full Text Available Leptospirosis is a zoonosis of global distribution that affects tropical and temperate areas. Under suitable conditions, Leptospira can survive in water and soil and contribute to human and animal infections. The objective of this study was to describe the presence of pathogenic Leptospira in peri-domestic water samples from rural households in southern Chile. Water samples, including puddles, containers, animal troughs, rivers, canals, and drinking water were collected from 236 households and tested for Leptospira using a PCR assay targeting the lipL32 gene. Evidence of Leptospira presence was detected in all sample types; overall, 13.5% (77/570 samples tested positive. A total of 10/22 (45.5% open containers, 12/83 (14.5% animal drinking sources, 9/47 (19.1% human drinking sources, and 36/306 (19.3% puddles tested positive. Lower income (OR = 4.35, p = 0.003, increased temperature (OR = 1.23, p < 0.001, and presence of dogs (OR = 15.9, p = 0.022 were positively associated with positive puddles. Increased number of rodent signs was associated with positive puddles in the household (OR = 3.22; however, only in the lower income households. There was no association between PCR positive rodents and puddles at the household level. Results revealed the ubiquity of Leptospira in the household environment and highlight the need to develop formal approaches for systematic monitoring.

Serological survey of antibodies to Toxoplasma gondii and Coxiella burnetii in rodents in north-western African islands (Canary Islands and Cape Verde).

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Foronda, Pilar; Plata-Luis, Josué; del Castillo-Figueruelo, Borja; Fernández-Álvarez, Ángela; Martín-Alonso, Aarón; Feliu, Carlos; Cabral, Marilena D; Valladares, Basilio

2015-05-29

Coxiella burnetii and Toxoplasma gondii are intracellular parasites that cause important reproductive disorders in animals and humans worldwide, resulting in high economic losses. The aim of the present study was to analyse the possible role of peridomestic small mammals in the maintenance and transmission of C. burnetii and T. gondii in the north-western African archipelagos of the Canary Islands and Cape Verde, where these species are commonly found affecting humans and farm animals. Between 2009 and 2013, 108 black rats (Rattus rattus) and 77 mice (Mus musculus) were analysed for the presence of Coxiella and Toxoplasma antibodies by enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence (IFA), respectively. Our results showed a wide distribution of C. burnetii and T. gondii, except for T. gondii in Cape Verde, in both rodent species. The overall seroprevalence of C. burnetii antibodies was 12.4%; 21.1% for Cape Verde and 10.2% for the Canary Islands. With respect to T. gondii, seropositive rodents were only observed in the Canary Islands, with an overall seroprevalence of 15%. Considering the fact that both pathogens can infect a large range of hosts, including livestock and humans, the results are of public health and veterinary importance and could be used by governmental entities to manage risk factors and to prevent future cases of Q fever and toxoplasmosis.

Seroprevalence of antibodies against the excreted antigen superoxide dismutase by Trypanosoma cruzi in dogs from the Yucatan Peninsula (Mexico).

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López-Cespedes, A; Longoni, S S; Sauri-Arceo, C H; Rodríguez-Vivas, R I; Villegas, N; Escobedo-Ortegón, J; Barrera-Pérez, M A; Sánchez-Moreno, M; Bolio González, M E; Marín, C

2013-06-01

Numerous studies have shown the role of dogs as a reservoir for the American trypanosomiasis, as the bridge connecting sylvatic and peridomestic cycles. The objective of this study was to determine the prevalence of American trypanosomiasis in the dog population (630 sera) from seven localities in the Yucatan Peninsula (city of Mérida and the towns of Molas, Playa del Carmen, Akumal, Xcalacoop, Xcalac and Xahuachol). These data are key for developing control measures for the disease. The sera were analysed to detect antibodies against Trypanosoma cruzi, using Fe-SOD excreted as the antigenic fraction by ELISA and Western blot as confirmation. The total prevalence found in the Yucatan Peninsula was some 14.76%, with 10.74% in the state of Yucatan (city of Mérida, towns of Molas and Xcalacoop) and 21.34% in the state of Quintana Roo (towns of Playa del Carmen, Akumal, Xcalac and Xahuachol). However, a more thorough epidemiological study of the dog population, both wild and urban, in the Yucatan Peninsula will be required to design a control strategy for these diseases, paying particular attention to the population affected and even broadening the study to other Mexican states as well as neighbouring countries. These results again confirm that iron-superoxide dismutase excreted by T. cruzi constitutes a good source of antigen for serodiagnosis in epidemiological studies. © 2012 Blackwell Verlag GmbH.

Serological Evidence of Hantavirus Infection in Apparently Healthy People from Rural and Slum Communities in Southern Chile

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Claudia Muñoz-Zanzi

2015-04-01

Full Text Available Hantavirus disease in America has been recognizable because of its rapid progression in clinical cases, occurrence in previously healthy young adults, and high case fatality rate. Hantavirus disease has been proposed now to define the diversity of clinical manifestations. Since 1995, a total of 902 cases of hantavirus pulmonary syndrome have been reported in Chile, caused by Andes virus (ANDV, with overall fatality of 32%. This report describes the sero-epidemiology of hantavirus in apparently healthy people in rural and urban slum communities from southern Chile. Ten of 934 samples yielded a positive result resulting in a seroprevalence of 1.07% (95% confidence intervals: 0.05%–2.0%. A higher proportion of positive samples was found among individuals from rural villages (1.3% and slums (1.5% compared with farms (0.5%. Seropositivity was associated with age (p = 0.011, low education level (p = 0.006 and occupations linked to the household (homemaker, retired, or student (p = 0.016. No evidence of infection was found in 38 sigmodontinae rodents trapped in the peri-domestic environment. Our findings highlight that exposure risk was associated with less documented risk factors, such as women in slum and rural villages, and the occurrence of infection that may have presented as flu-like illness that did not require medical attention or was misdiagnosed.

A novel video-tracking system to quantify the behaviour of nocturnal mosquitoes attacking human hosts in the field.

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Angarita-Jaimes, N C; Parker, J E A; Abe, M; Mashauri, F; Martine, J; Towers, C E; McCall, P J; Towers, D P

2016-04-01

Many vectors of malaria and other infections spend most of their adult life within human homes, the environment where they bloodfeed and rest, and where control has been most successful. Yet, knowledge of peri-domestic mosquito behaviour is limited, particularly how mosquitoes find and attack human hosts or how insecticides impact on behaviour. This is partly because technology for tracking mosquitoes in their natural habitats, traditional dwellings in disease-endemic countries, has never been available. We describe a sensing device that enables observation and recording of nocturnal mosquitoes attacking humans with or without a bed net, in the laboratory and in rural Africa. The device addresses requirements for sub-millimetre resolution over a 2.0 × 1.2 × 2.0 m volume while using minimum irradiance. Data processing strategies to extract individual mosquito trajectories and algorithms to describe behaviour during host/net interactions are introduced. Results from UK laboratory and Tanzanian field tests showed that Culex quinquefasciatus activity was higher and focused on the bed net roof when a human host was present, in colonized and wild populations. Both C. quinquefasciatus and Anopheles gambiae exhibited similar behavioural modes, with average flight velocities varying by less than 10%. The system offers considerable potential for investigations in vector biology and many other fields. © 2016 The Authors.

Insecticidal Properties of Essential Oils and Some of Their Constituents on the Turkestan Cockroach (Blattodea: Blattidae).

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Gaire, Sudip; O'Connell, Mary; Holguin, Francisco O; Amatya, Anup; Bundy, Scott; Romero, Alvaro

2017-04-01

The Turkestan cockroach, Blatta lateralis (Walker), has become the most important peridomestic species in urban areas of the Southwestern United States. The aim of this study was to evaluate the use of botanical compounds to control this urban pest. We tested the acute toxicity and repellency of six botanical constituents and three essential oils on Turkestan cockroach nymphs. Chemical composition of the essential oils was also determined. Topical and fumigant assays with nymphs showed that thymol was the most toxic essential oil constituent, with a LD50 of 0.34 mg/nymph and a LC50 of 27.6 mg/liter air, respectively. Contact toxicity was also observed in assays with trans-Cinnamaldehyde, eugenol, geraniol, methyl eugenol, and p-Cymene. Methyl eugenol and geraniol had limited fumigant toxicity. The essential oils from red thyme, clove bud, and Java citronella exhibited toxicity against nymphs. Cockroaches avoided fresh dry residues of thymol and essential oils. Chemical analysis of the essential oils confirmed high contents of effective essential oil constituents. Our results demonstrated that essential oils and some of their constituents have potential as eco-friendly insecticides for the management of Turkestan cockroaches. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Ecology, feeding and natural infection by Leishmania spp. of phlebotomine sand flies in an area of high incidence of American tegumentary leishmaniasis in the municipality of Rio Branco, Acre, Brazil.

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de Ávila, Márcia Moreira; Brilhante, Andreia Fernandes; de Souza, Cristian Ferreira; Bevilacqua, Paula Dias; Galati, Eunice Aparecida Bianchi; Brazil, Reginaldo Peçanha

2018-01-26

Phlebotomine sand flies (Diptera: Psychodidae) are insects of medical importance due to their involvement in the zoonotic transmission of Leishmania spp. to vertebrates. The aim of this work was to study the ecology of the sand fly fauna of two types of environments, a rural environment (the Transacreana Road) and an urban park (Horto Florestal Park), both located in the municipality of Rio Branco in the state of Acre, Brazil. Additionally, this study intended to investigate Leishmania infection and blood meal sources of these sand flies using molecular techniques. The sand fly fauna was studied in different environments (i.e. forest and peridomestic environments in a rural area, and an urban forest) using Shannon traps and HP light traps to collect sand fly specimens over 13 consecutive months (December 2014 to January 2016). For investigating natural infection by Leishmania and the source of sand fly blood meals, DNA samples were extracted from female sand flies and subjected to polymerase chain reaction targeting ITS1 and cytb genes. DNA sequencing was subsequently used to identify species of Leishmania and the source of blood meals. A total of 2515 individual sand flies of 43 species were collected and identified, Trichophoromyia auraensis (839; 33.35%), Trichophoromyia spp. (537; 21.35%) and Evandromyia saulensis (187; 7.43%) were more abundant in the rural area (S = 41 species) than in the urban forest. No significant differences were found in species richness between forest and peridomestic environments in the rural area (H = 0.04; P > 0.05), but a larger number of species was found in the forest. Leishmania DNA was sequenced in 13 samples, confirming the presence of L. (V.) braziliensis in Th. auraensis (n = 1), Ev. saulensis (n = 2), Ev. walkeri (n = 1), Ps. llanosmartinsi (n = 1), Pi. nevesi (n = 2), Ps. davisi (n = 1), Ps. ayrozai (n = 1), Pa. aragaoi (n = 1), Ny. antunesi (n = 1) and Ev. infraspinosa (n�

Residual effect of a micro-encapsulated formulation of organophosphates and piriproxifen on the mortality of deltamethrin resistant Triatoma infestans populations in rural houses of the Bolivian Chaco region

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Abraham Gemio Alarico

2010-09-01

Full Text Available The Bolivian Chaco is part of the endemic region of Chagas disease and an area where pyrethroid resistant Triatoma infestans (Hemiptera: Reduviidae populations has been reported. The World Health Organization identified these resistant populations as an important focus for research. The objective of this study was to evaluate the residual effect of a micro-encapsulated formulation containing organophosphate active ingredients and a juvenile hormone analogue (Inesfly 5A IGR on the mortality of T. infestans. Studies took place in rural houses of the Bolivian Chaco that were treated up to 34 months before and evaluated the susceptibility to pyrethroids of the offspring of field collected insects. Thirty houses were randomly selected within three communities to carry out wall bio-assays with T. infestans nymphs. Mortality was recorded 24, 48 and 72 h after wall contact. Eggs laid by females collected in the area were used to obtain first-instar nymphs and carry out pyrethroid susceptibility tests. The wall bio-assays showed that the micro-encapsulated insecticide eliminates T. infestans populations and produces detectable mortality of insects exposed to walls treated 34 months prior to the tests. The discriminant dose of deltamethrin (0.01 mg/mL showed 65% nymph survival, whereas at the highest tested dose (1.0 mg/mL 14% of the nymphs survived. These results show that Inesfly 5A IGR is an appropriate tool for the elimination of intradomestic and peridomestic populations of T. infestans resistant to pyrethroids.

First record of Triatoma maculata (Erichson, 1848 (Hemiptera: Reduviidae: Triatomini in Riohacha, La Guajira – Colombia

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Edith Natalia Gómez-Melendro

2014-11-01

Full Text Available Introduction. Knowledge of vector insect species, their habitat and geographical distribution is crucial for determining the risk of transmission of the etiologic agents that cause disease in humans, which allows defining strategies for prevention, surveillance and control in line with the characteristics of each area. Objective. To determine the presence and public health importance of vectors of Chagas disease in the indigenous settlements of Marbacella and El Horno of the Wayúu ethnic group in the municipality of Riohacha, La Guajira, Colombia. Materials and methods. From active search, installation and inspection of biosensors and occasional catches, Hemiptera: Reduviidae: Triatomini were collected intra and in the peridomicile housing of the indigenous settlements of El Horno and Marbacella of the the Wayúu ethnic group. Indices of intra and peridomestic infestation, colonization, density, dispersion and natural infection with Trypanosoma cruzi Chagas, 1909 were calculated. Results. 79.6% (n = 90 of the specimens were collected around the homes and 20.3% (n = 23 inside the homes, all corresponding to Triatoma maculata (Erichson, 1848. The natural infection indices with T. cruzi accounted for 43.5% for Marbacella and 36% for El Horno. Conclusion. This is the first reported capture of individuals of T. maculata, considered a secondary vector of Chagas disease in Colombia, naturally infected with T. cruzi in the municipality of Riohacha expanding the geographical distribution of the species in the department of La Guajira.

Xenosurveillance reflects traditional sampling techniques for the identification of human pathogens: A comparative study in West Africa.

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Joseph R Fauver

2018-03-01

Full Text Available Novel surveillance strategies are needed to detect the rapid and continuous emergence of infectious disease agents. Ideally, new sampling strategies should be simple to implement, technologically uncomplicated, and applicable to areas where emergence events are known to occur. To this end, xenosurveillance is a technique that makes use of blood collected by hematophagous arthropods to monitor and identify vertebrate pathogens. Mosquitoes are largely ubiquitous animals that often exist in sizable populations. As well, many domestic or peridomestic species of mosquitoes will preferentially take blood-meals from humans, making them a unique and largely untapped reservoir to collect human blood.We sought to take advantage of this phenomenon by systematically collecting blood-fed mosquitoes during a field trail in Northern Liberia to determine whether pathogen sequences from blood engorged mosquitoes accurately mirror those obtained directly from humans. Specifically, blood was collected from humans via finger-stick and by aspirating bloodfed mosquitoes from the inside of houses. Shotgun metagenomic sequencing of RNA and DNA derived from these specimens was performed to detect pathogen sequences. Samples obtained from xenosurveillance and from finger-stick blood collection produced a similar number and quality of reads aligning to two human viruses, GB virus C and hepatitis B virus.This study represents the first systematic comparison between xenosurveillance and more traditional sampling methodologies, while also demonstrating the viability of xenosurveillance as a tool to sample human blood for circulating pathogens.

Home hygiene and environmental sanitation: a country situation analysis for India.

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Nath, K J

2003-06-01

Problems of the environment and of domestic hygiene are always related to poverty of population and the sanitation of settlements. Most cities and towns in developing countries, like India, are characterised by over-crowding, congestion, inadequate water supply and inadequate facilities of disposal of human excreta, waste water and solid wastes. Inadequacy of housing for most urban poor invariably leads to poor home hygiene. Personal and domestic hygiene practices cannot be improved without improving basic amenities, such as water supply, waste water disposal, solid waste management and the problems of human settlements. But even under the prevailing conditions, there is significant scope of improving hygiene practices at home to prevent infection and cross-infection. Unfortunately, in developing countries, public health concerns are usually raised on the institutional setting, such as municipal services, hospitals, environmental sanitation, etc. There is a reluctance to acknowledge the home as a setting of equal importance along with the public institutions in the chain of disease transmission in the community. Managers of home hygiene and community hygiene must act in unison to optimise return from efforts to promote public health. Current practices and perceptions of domestic and personal hygiene in Indian communities, the existing levels of environmental and peri-domestic sanitation and the 'health risk' these pose will be outlined, as well as the need for an integrated action for improving hygiene behaviour and access to safe water and sanitation.

Evidence of Two Cocirculating Canine Distemper Virus Strains in Mesocarnivores from Northern Colorado.

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Wostenberg, Darren J; Walker, Nikki; Fox, Karen A; Spraker, Terry R; Piaggio, Antoinette J; Gilbert, Amy

2018-03-02

Canine distemper virus (CDV) is a highly contagious pathogen that principally infects wildlife and domestic carnivores. Peridomestic species such as raccoons ( Procyon lotor) experience outbreaks with high mortality. Clinical signs of infection include anorexia, fever, respiratory infection, and neurologic complications. Although not zoonotic, CDV poses a high risk to unvaccinated domestic animals and the conservation of endangered species. During 2013-2016, we opportunistically collected wild and domestic carnivore specimens through a rabies surveillance program in northern Colorado. Brainstem and cerebellar tissue samples were independently tested for rabies and CDV by fluorescent antibody test. We tested a total of 478 animals for CDV, comprised of 10 wild and domestic carnivore species. A total of 24% (71/300) raccoons and 4% (1/26) coyotes ( Canis latrans) tested positive for CDV, but coinfection with rabies virus was not observed among CDV-positive animals. We extracted RNA from positive tissues, and a reverse-transcription PCR was used to create complementary DNA. We amplified and sequenced the hemagglutinin gene from 60 CDV-positive tissues, and a median joining network and maximum likelihood phylogenetic tree revealed two major lineages among samples. Phylogenetic analysis indicated that our sequences were most similar to: 1) the America-2 ( n=55) and 2) the America-3 ( n=5) CDV lineages circulating in North America. Our results indicated two distinct and distantly related clades of CDV overlapping geographically and temporally among raccoon populations in northern Colorado.

Prevalence, Genetic Characterization, and 18S Small Subunit Ribosomal RNA Diversity of Trypanosoma rangeli in Triatomine and Mammal Hosts in Endemic Areas for Chagas Disease in Ecuador.

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Ocaña-Mayorga, Sofia; Aguirre-Villacis, Fernanda; Pinto, C Miguel; Vallejo, Gustavo A; Grijalva, Mario J

2015-12-01

Trypanosoma rangeli is a nonpathogenic parasite for humans; however, its medical importance relies in its similarity and overlapping distribution with Trypanosoma cruzi, causal agent of Chagas disease in the Americas. The genetic diversity of T. rangeli and its association with host species (triatomines and mammals) has been identified along Central and the South America; however, it has not included data of isolates from Ecuador. This study reports infection with T. rangeli in 18 genera of mammal hosts and five species of triatomines in three environments (domestic, peridomestic, and sylvatic). Higher infection rates were found in the sylvatic environment, in close association with Rhodnius ecuadoriensis. The results of this study extend the range of hosts infected with this parasite and the geographic range of the T. rangeli genotype KP1(-)/lineage C in South America. It was not possible to detect variation on T. rangeli from the central coastal region and southern Ecuador with the analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, even though these areas are ecologically different and a phenotypic subdivision of R. ecuadoriensis has been found. R. ecuadoriensis is considered one of the most important vectors for Chagas disease transmission in Ecuador due to its wide distribution and adaptability to diverse environments. An extensive knowledge of the trypanosomes circulating in this species of triatomine, and associated mammal hosts, is important for delineating transmission dynamics and preventive measures in the endemic areas of Ecuador and Northern Peru.

Prevalence, Genetic Characterization, and 18S Small Subunit Ribosomal RNA Diversity of Trypanosoma rangeli in Triatomine and Mammal Hosts in Endemic Areas for Chagas Disease in Ecuador

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Ocaña-Mayorga, Sofia; Aguirre-Villacis, Fernanda; Pinto, C. Miguel; Vallejo, Gustavo A.

2015-01-01

Abstract Trypanosoma rangeli is a nonpathogenic parasite for humans; however, its medical importance relies in its similarity and overlapping distribution with Trypanosoma cruzi, causal agent of Chagas disease in the Americas. The genetic diversity of T. rangeli and its association with host species (triatomines and mammals) has been identified along Central and the South America; however, it has not included data of isolates from Ecuador. This study reports infection with T. rangeli in 18 genera of mammal hosts and five species of triatomines in three environments (domestic, peridomestic, and sylvatic). Higher infection rates were found in the sylvatic environment, in close association with Rhodnius ecuadoriensis. The results of this study extend the range of hosts infected with this parasite and the geographic range of the T. rangeli genotype KP1(−)/lineage C in South America. It was not possible to detect variation on T. rangeli from the central coastal region and southern Ecuador with the analysis of the small subunit ribosomal RNA (SSU-rRNA) gene, even though these areas are ecologically different and a phenotypic subdivision of R. ecuadoriensis has been found. R. ecuadoriensis is considered one of the most important vectors for Chagas disease transmission in Ecuador due to its wide distribution and adaptability to diverse environments. An extensive knowledge of the trypanosomes circulating in this species of triatomine, and associated mammal hosts, is important for delineating transmission dynamics and preventive measures in the endemic areas of Ecuador and Northern Peru. PMID:26645579

Inter-relation of sylvatic and domestic transmission of Trypanosoma cruzi in areas with and without domestic vectorial transmission in Minas Gerais, Brazil

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L. Diotaiuti

1995-08-01

Full Text Available During the period 1980-1986, we captured triatomine bugs and mammalian reservoir hosts from sylvatic and domestic situations in different municipalities of the State of Minas Gerais. Trypanosoma cruzi was isolated from captured bugs, mammals and patients. After cultivation in LIT medium, the electrophoretic enzyme profiles were determined. We obtained atotal of 32 parasite isolates from regions with active domestic transmission, and 24 isolates form areas under control. For the first areas the results suggest introduction of T. cruzi from sylvatic habitats, through incursion of infected opossums and/or sylvatic T. sordida, which appears to have given rise to at least one acute human infection. Of particular interest is the finding of sylvatic opossums and a T. sordida nymph infected with ZB, that could indicate return of parasites from chronic human infections to sylvatic transmission cycles. For the areas under control we also interpret the results as interaction between sylvatic and domestic cycles of transmission, here through the invasion of houses by bugs carrying the Z1 zymodeme from the sylvatic environment. The Multivariate Correspondence Analysis gives a spatial description between the different parasite isolates and confirms the existence of a bridge in the opposite direction in the region with active vectorial transmission including the exporting of Z2 through the peridomestic environment into the sylvatic cycle. For the others areas this bridge corresponds especially to Panstrongylus megistus, importing Z1 into the domestic environment.

Molecular epidemiology of Trypanosoma cruzi and Triatoma dimidiata in costal Ecuador.

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Wong, Yim Yan; Sornosa Macias, Karen Jeniffer; Guale Martínez, Doris; Solorzano, Luis F; Ramirez-Sierra, Maria Jesus; Herrera, Claudia; Dumonteil, Eric

2016-07-01

Chagas disease is a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi. In Ecuador, Triatoma dimidiata and Rhodnius ecuadoriensis are the main vector species, responsible for over half of the cases of T. cruzi infection in the country. T. dimidiata is believed to have been introduced in Ecuador during colonial times, and its elimination from the country is thus believed to be feasible. We investigated here the molecular ecology of T. dimidiata and T. cruzi in costal Ecuador to further guide control efforts. Analysis of the Internal Transcribed Spacer 2 (ITS-2) of 23 specimens from Progreso, Guayas, unambiguously supported the likely importation of T. dimidiata from Central America to Ecuador. The observation of a very high parasite infection rate (54%) and frequent feeding on humans (3/5) confirmed a continued risk of transmission to humans. All genotyped parasites corresponded to TcI DTU and Trypanosoma rangeli was not detected in T. dimidiata. TcI subgroups corresponded to TcIa (25%), and mixed infections with TcIa and TcId (75%). Further studies should help clarify T. cruzi genetic structure in the country, and the possible impact of the introduction of T. dimidiata on the circulating parasite strains. The elevated risk posed by this species warrants continuing efforts for its control, but its apparent mobility between peridomestic and domestic habitats may favor reinfestation following insecticide spraying. Copyright © 2016 Elsevier B.V. All rights reserved.

Epidemiología de la tripanosomiasis americana en el Norte de Corrientes Epidemiology of American trypanosomiasis in the North of Corrientes province, Argentina

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María Esther Bar

2010-04-01

in 2007 and 2008 in randomly selected households at rural areas. Diagnosis of Chagas infection in volunteer residents was performed using indirect hemagglutination, indirect immunofluorescence and indirect immunoenzimatic assay. Thirty human dwellings and 25 peridomestic ecotopes were searched at Berón de Astrada, and 32 houses and 33 peridomiciles at Mburucuyá. A total of 19 nymphs were captured in a chicken coop at Mburucuyá, the infestation rate was 3.0%. At Berón de Astrada 4.0% of the peridomiciles resulted infested by Triatoma sordida, a female and 58 eggs were collected in a hen nest. Trypanosoma cruzi infection was not detected in Triatoma sordida. The prevalence human rate was 5.2% (11/77 at Mburucuyá and 14.3% (4/77 at Berón de Astrada. Presence of triatomines was not confirmed at the human dwellings, and the infestation of the peridomestic structures was low. It is necessary to implement new strategies of vectorial control, especially for those species that prevail in the peridomicile and sylvatic ecotopes. Seroprevalence was lower that the observed in previous investigations in other rural areas of Corrientes. The absence of seroreactives in the 0-10 age group suggests a halt in T. cruzi transmission in the studied area.

Diversidad, patrones de uso y conservación de palmas Arecaceae en bosques pluviales del Chocó, Colombia

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Hamleth Valois-Cuesta

2013-12-01

Full Text Available La familia Arecaceae es rica en especies, principalmente en el trópico, y constituye una fuente de recursos para la subsistencia de sus pobladores. En el presente trabajo se estudió la riqueza, diversidad, composición y patrones de uso de la familia Arecaceae en tres localidades de la cuenca media del río Atrato en el Chocó, Colombia, con el fin de obtener información que permita su conservación y uso sostenible. Se registraron 29 especies en 18 géneros, siendo Bactris 24.13 y Wettinia 10.34 los géneros más ricos en especies. El Buey mostró más especies y géneros 23 especies, 17 géneros que Beté 15 y 10 respectivamente y Tanguí 14 y 11 respectivamente. La similitud florística entre localidades fue menor al 45. Las especies con mayor peso ecológico y valor de uso fueron: Euterpe oleracea Mart., Oenocarpus bataua Mart., Attalea allennii H.E. Moore, Manicaria saccifera Gaertn., Bactris gassipaes Kunth y Wettinia quinaria O.F.Cook y Doyle R. Bernal. Las categorías de uso con mayor riqueza de especies e importancia cultural fueron: construcción, alimento y uso artesanal; y los órganos más usados fueron tallos y frutos. Los resultados de este trabajo demuestran que el Atrato Medio posee alta riqueza y diversidad de especies de palmas en un contexto regional y nacional. Sin embargo, la relación entre el número de uso y la importancia ecológica de la especie depende de la localidad, lo que indica que la importancia socio-cultural de la especie puede variar entre grupos humanos que comparten una misma cultura o región biogeográfica. Se publicarán estudios a futuro para determinar el papel del tipo de órgano utilizado como materia prima en la demografía y dinámica ecológica de las poblaciones de palma en el Chocó y otras regiones del Neotrópico.

First recorded outbreak of yellow fever in Kenya, 1992-1993. II. Entomologic investigations.

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Reiter, P; Cordellier, R; Ouma, J O; Cropp, C B; Savage, H M; Sanders, E J; Marfin, A A; Tukei, P M; Agata, N N; Gitau, L G; Rapuoda, B A; Gubler, D J

1998-10-01

The first recorded outbreak of yellow fever in Kenya occurred from mid-1992 through March 1993 in the south Kerio Valley, Rift Valley Province. We conducted entomologic studies in February-March 1993 to identify the likely vectors and determine the potential for transmission in the surrounding rural and urban areas. Mosquitoes were collected by landing capture and processed for virus isolation. Container surveys were conducted around human habitation. Transmission was mainly in woodland of varying density, at altitudes of 1,300-1,800 m. The abundance of Aedes africanus in this biotope, and two isolations of virus from pools of this species, suggest that it was the principal vector in the main period of the outbreak. A third isolate was made from a pool of Ae. keniensis, a little-known species that was collected in the same biotope. Other known yellow fever vectors that were collected in the arid parts of the valley may have been involved at an earlier stage of the epidemic. Vervet monkeys and baboons were present in the outbreak area. Peridomestic mosquito species were absent but abundant at urban sites outside the outbreak area. The entomologic and epidemiologic evidence indicate that this was a sylvatic outbreak in which human cases were directly linked to the epizootic and were independent of other human cases. The region of the Kerio Valley is probably subject to recurrent wandering epizootics of yellow fever, although previous episodes of scattered human infection have gone unrecorded. The risk that the disease could emerge as an urban problem in Kenya should not be ignored.

Environmental Determinants of the Distribution of Chagas Disease Vector Triatoma dimidiata in Colombia.

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Parra-Henao, Gabriel; Quirós-Gómez, Oscar; Jaramillo-O, Nicolas; Cardona, Ángela Segura

2016-04-01

Triatoma dimidiata (Hemiptera: Reduviidae) is a secondary vector of Trypanosoma cruzi in Colombia and represents an important epidemiological risk mainly in the central and oriental regions of the country where it occupies sylvatic, peridomestic, and intradomestic ecotopes, and because of this complex distribution, its distribution and abundance could be conditioned by environmental factors. In this work, we explored the relationship between T. dimidiata distribution and environmental factors in the northwest, northeast, and central zones of Colombia and developed predictive models of infestation in the country. The associations between the presence ofT. dimidiata and environmental variables were studied using logistic regression models and ecological niche modeling for a sample of villages in Colombia. The analysis was based on the information collected in field about the presence ofT. dimidiata and the environmental data for each village extracted from remote sensing images. The presence of Triatoma dimidiata(Latreille, 1811) was found to be significantly associated with the maximum vegetation index, minimum land surface temperature (LST), and the digital elevation for the statistical model. Temperature seasonality, annual precipitation, and vegetation index were the variables that most influenced the ecological niche model ofT. dimidiata distribution. The logistic regression model showed a good fit and predicted suitable habitats in the Andean and Caribbean regions, which agrees with the known distribution of the species, but predicted suitable habitats in the Pacific and Orinoco regions proposing new areas of research. Improved models to predict suitable habitats forT. dimidiata hold promise for spatial targeting of integrated vector management. © The American Society of Tropical Medicine and Hygiene.

Ecological aspects of the sandfly fauna (Diptera, Psychodidae in an American cutaneous leishmaniasis endemic area under the influence of hydroelectric plants in Paranapanema river, State of Paraná, Brazil

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Mariza Fordellone Rosa Cruz

2012-08-01

Full Text Available INTRODUCTION: An epidemiological study was undertaken to identify determinant factors in the occurrence of American cutaneous leishmaniasis in areas under the influence of hydroelectric plants in Paranapanema river, State of Paraná, Brazil. The ecological aspects of the phlebotomine fauna were investigated. METHODS: Sandflies were sampled with automatic light traps from February 2004 to June 2006 at 25 sites in the urban and rural areas of Itambaracá, and in Porto Almeida and São Joaquim do Pontal. RESULTS: A total of 3,187 sandflies of 15 species were captured. Nyssomyia neivai predominated (34.4%, followed by Pintomyia pessoai (32.6%, Migonemyia migonei (11.6%, Nyssomyia whitmani (8.8%, and Pintomyia fischeri (2.7%, all implicated in the transmission of Leishmania. Males predominated for Ny. neivai, and females for the other vector species, with significant statistical differences (p < 0.001. Nyssomyia neivai, Pi. pessoai, Ny. whitmani, Brumptomyia brumpti, Mg. migonei, and Pi. fischeri presented the highest values for the Standardized Species Abundance Index (SSAI. The highest frequencies and diversities were found in the preserved forest in Porto Almeida, followed by forests with degradation in São Joaquim do Pontal and Vila Rural. CONCLUSIONS: Sandflies were captured in all localities, with the five vectors predominating. Ny. neivai had its highest frequencies in nearby peridomestic environments and Pi. pessoai in areas of preserved forests. The highest SSAI values of Ny. neivai and Pi. pessoai reflect their wider dispersion and higher frequencies compared with other species, which seems to indicate that these two species may be transmitting leishmaniasis in the area.

Larval mosquito habitat utilization and community dynamics of Aedes albopictus and Aedes japonicus (Diptera: Culicidae).

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Bartlett-Healy, Kristen; Unlu, Isik; Obenauer, Peter; Hughes, Tony; Healy, Sean; Crepeau, Taryn; Farajollahi, Ary; Kesavaraju, Banu; Fonseca, Dina; Schoeler, George; Gaugler, Randy; Strickman, Daniel

2012-07-01

Aedes albopictus (Skuse) and Ae. japonicus (Theobald) are important container-inhabiting mosquitoes that transmit disease agents, outcompete native species, and continue to expand their range in the United States. Both species deposit eggs in natural and artificial containers and thrive in peridomestic environments. The goal of our study was to examine the types and characteristics of containers that are most productive for these species in the northeastern United States. In total, 306 containers were sampled in urban, suburban, and rural areas of New Jersey. Multiple biotic and abiotic factors were recorded in an attempt to identify variables associated with the productivity of each species. Based on pupal abundance and density of container types, results showed that tires, trash cans, and planter dishes were the most important containers for Ae. albopictus, while planter dishes were the most important containers for Ae. japonicus. Container color (black and gray), material (rubber), and type (tires) were correlated with species presence for Ae. albopictus and Ae. japonicus. These factors may play a role in the selection of oviposition sites by female mosquitoes or in the survival of their progeny. Differences in species composition and abundance were detected between areas classified as urban, suburban, and rural. In urban and suburban areas, Ae. albopictus was more abundant in container habitats than Ae. japonicus; however, Ae. japonicus was more abundant in rural areas, and when water temperatures were below 14 degrees C. Our results suggest many variables can influence the presence of Ae. albopictus and Ae. japonicus in container habitats in northeastern United States.

Ticks infesting wild and domestic animals and humans of Sri Lanka with new host records.

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Liyanaarachchi, D R; Rajakaruna, R S; Dikkumbura, A W; Rajapakse, R P V J

2015-02-01

An island-wide collection of tick species infesting humans, domesticated and wild animals and questing ticks in domestic and peridomestic environments was carried out during 2009-2011. A total of 30,461 ticks were collected from 30 different hosts and free living stages from the ground. The collection consisted of 22 tick species from 30 different hosts recording 12 tick species from humans, 19 from domesticated animals and 21 from wild animals, with a total of 97 new host records. The most common tick species on humans were Dermacentor auratus and Amblyomma testudinairum, while Haemaphysalis intermedia, Rhipicephalus microplus and Rhipicephalus sanguineus were common in domesticated and wild animals sharing 20 host species. Among the questing ticks, immature D. auratus was the most abundant. Humans and domesticated animals were mostly infested by the nymphal stages while adult ticks were found on wild animals. High number of new host records could be due to domestic animals picking tick species from wildlife and vise versa at the human/animal interface. Habitat destruction due to forest fragmentation has lead to wild animals roaming in urban and semi-urban neighbourhoods increasing the interactions of wild animals with domesticated animals. Wild animals play a significant role as a reservoir of many tick borne infections which can easily be spread to domesticated animals and then to humans via tick infestations. Data in this paper are useful for those interested in tick infesting wild and domestic animals and humans in describing the zoonotic potential of tick borne infections. Copyright © 2014 Elsevier B.V. All rights reserved.

An anti-mosquito mixture for domestic use, combining a fertiliser and a chemical or biological larvicide.

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Darriet, Frédéric

2016-07-01

Plant saucers are an important larval habitat for Aedes aegypti and Ae. albopictus in peridomestic situations. Because NPK fertilisers in plant containers tend to enhance the oviposition of these species, we investigated the effects of Bacillus thuringiensis var. israelensis, spinosad, pyriproxyfen and diflubenzuron larvicides in combination with fertiliser on the adult emergence and fecundity of the mosquitoes coming from plant saucers in controlled greenhouse experiments. NPK + larvicide (NPK-LAV) treatments were tested on Ae. aegypti. Each treatment was compared with water and with fertiliser alone on a total of five houseplants and their saucers. The fertilising treatment was renewed every 30-45 days. With less than 5% imaginal emergence, the NPK + spinosad 0.5% treatment remained effective for 30 days. Both NPK + pyriproxyfen 0.1% and NPK + diflubenzuron 0.25% were effective for 45 days. The average number of eggs laid in the three treatments was similar to the NPK treatment, indicating that spinosad, pyriproxyfen and diflubenzuron did not alter the attraction effect of the fertiliser on egg laying. NPK + pyriproxyfen and NPK + diflubenzuron also had ovicidal activity and an important impact on the fecundity of the Ae. aegypti female imagos and the fertility of their eggs. The addition of NPK fertiliser to insecticides can increase larval control of Aedes mosquitoes. This innovative measure for personal protection, which is harmless for both humans and animals, would be an additional support for the community-based actions led by the institutional services for vector control. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Novel H7N2 and H5N6 Avian Influenza A Viruses in Sentinel Chickens: A Sentinel Chicken Surveillance Study

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Teng Zhao

2016-11-01

Full Text Available In 2014, surveillance of sentinel chicken for avian influenza virus was conducted in aquatic bird habitat near Wuxi City, Jiangsu Province, China. Two H7N2, one H5N6, and two H9N2 viruses were isolated. Sequence analysis revealed that the H7N2 virus is a novel reassortant of H7N9 and H9N2 viruses and H5N6 virus is a reassortant of H5N1 clade 2.3.4 and H6N6 viruses. Substitutions V186 and L226 (H3 numbering in the hemagglutinin (HA gene protein was found in two H7N2 viruses but not in the H5N6 virus. Two A138 and A160 mutations were identified in the HA gene protein of all three viruses but a P128 mutation was only in the H5N6 virus. A deletion of three and eleven amino acids in the neuraminidase stalk region was found in two H7N2 and H5N6 viruses, respectively. Moreover, a mutation of N31 in M2 protein was observed in both two H7N2 viruses. High similarity of these isolated viruses to viruses previously identified among poultry and humans, suggests that peridomestic aquatic birds may play a role in sustaining novel virus transmission. Therefore, continued surveillance is needed to monitor these avian influenza viruses in wild bird and domestic poultry that may pose a threat to poultry and human health.

The first report of Hepatozoon canis identified in Vulpes vulpes and ticks from Italy.

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Gabrielli, Simona; Kumlien, Susanna; Calderini, Pietro; Brozzi, Alberto; Iori, Albertina; Cancrini, Gabriella

2010-11-01

This is the first report on the presence of Hepatozoon canis in Vulpes vulpes in Italy. During the years 2005 and 2006, a total of 119 foxes were collected and their spleen tissues were screened by microscopy, polymerase chain reaction, and sequencing. In the same area, 290 ticks were picked off from dogs or collected from the environment. Microscopy detected inclusion bodies regarded as belonging to the genus Hepatozoon in four samples, whereas molecular diagnostics evidenced 16 foxes (13.4%) and 6 ticks (2.1%) positive to H. canis. The H. canis isolates we found in foxes, compared with the strains we previously detected in dogs from the same area and with the strains found in foxes from other European countries, show a certain genetic heterogeneity. In fact, seven isolates cluster with the Italian dog strain and nine isolates cluster with the fox strain found in Spain and Slovakia; moreover, the dog's strain is closely related to one tick's isolate, and the strain found in three Rhipicephalus sanguineus and in one Ixodes ricinus collected from the environment cluster with the aforementioned Spanish and Slovak fox strains. Our findings confirm the importance of R. sanguineus as final host and suggest that I. ricinus might also be implicated in parasite transmission, explaining in that way the occurrence of hepatozoonosis in areas considered R. sanguineus-free. The peridomestic habits of V. vulpes and the increasing global temperature are expected to amplify the impact of this vector-borne disease and to enforce the transmission of Hepatozoon to domestic animals.

Triatomines in dwellings and outbuildings in an endemic area of Chagas disease in northeastern Brazil

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Antonio Fernando Rodrigues Lima

2012-12-01

Full Text Available INTRODUCTION: The present study identified the triatomines collected in intra and peri-domestic environments, observed the occurrence of Trypanosoma cruzi infection in triatomines and correlated this information with housing conditions and the fauna associated with the rural areas of the City of Itabaianinha, located in the State of Sergipe, Brazil. METHODS: Quarterly visits were conducted between March 2009 and March 2010, and the homes to be visited for the active search of insects were determined by random selection. In each housing unit, the insects were collected by a manual search with a metal clip and flashlight to inspect openings and cavities, with a collection time of one hour/home/individual. The Pirisa® dislodge chemical was used to force the insects to leave their ecotopes. Analysis of the intestinal contents of triatomines was performed in the laboratory to establish the presence of Trypanosomatidae. RESULTS: Of the 103 dwellings surveyed, 17.5% were infested with Panstrongylus megistus. The village of Mutuca exhibited the highest infestation rate (38.1%. All the villages with relevant infestation rates were situated in the northern area of the city. The highest percentage of vector infection was found in the village of Água Boa (56.5%. The rural dwellings were found to be primarily brick or wooden house with or without roughcast or plastered walls, and the outbuilding most frequently associated with triatomines was the chicken run. CONCLUSIONS: These results emphasise the need for broader vector control and surveillance and for educational campaigns in the context of the Chagas Disease Control Program.

Triatomines in dwellings and outbuildings in an endemic area of Chagas disease in northeastern Brazil.

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Lima, Antonio Fernando Rodrigues; Jeraldo, Veronica de Lourdes Sierpe; Silveira, Maxwell Souza; Madi, Rubens Riscala; Santana, Thiago Bicudo Krempel; Melo, Cláudia Moura de

2012-12-01

The present study identified the triatomines collected in intra and peri-domestic environments, observed the occurrence of Trypanosoma cruzi infection in triatomines and correlated this information with housing conditions and the fauna associated with the rural areas of the City of Itabaianinha, located in the State of Sergipe, Brazil. Quarterly visits were conducted between March 2009 and March 2010, and the homes to be visited for the active search of insects were determined by random selection. In each housing unit, the insects were collected by a manual search with a metal clip and flashlight to inspect openings and cavities, with a collection time of one hour/home/individual. The Pirisa® dislodge chemical was used to force the insects to leave their ecotopes. Analysis of the intestinal contents of triatomines was performed in the laboratory to establish the presence of Trypanosomatidae. Of the 103 dwellings surveyed, 17.5% were infested with Panstrongylus megistus. The village of Mutuca exhibited the highest infestation rate (38.1%). All the villages with relevant infestation rates were situated in the northern area of the city. The highest percentage of vector infection was found in the village of Água Boa (56.5%). The rural dwellings were found to be primarily brick or wooden house with or without roughcast or plastered walls, and the outbuilding most frequently associated with triatomines was the chicken run. These results emphasise the need for broader vector control and surveillance and for educational campaigns in the context of the Chagas Disease Control Program.

Factors associated with Leishmania chagasi infection in domestic dogs from Teresina, State of Piauí, Brazil

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João Pereira da Silva

2012-08-01

Full Text Available INTRODUCTION: Many studies have evaluated risk factors for human visceral leishmaniasis, but few have focused on the infection among dogs. The objective of this study was to assess the association between peridomestic socioeconomic and environmental factors and the presence of dogs seropositive for Leishmania chagasi in the City of Teresina, Brazil. METHODS: This case-control study was based on the results of a routine seroepidemiological survey among domestic dogs carried out in 2007. Serological tests were performed by means of indirect immunofluorescence antibody test. All dwellings in which at least one seropositive dog was detected were considered cases, and controls were a random sample of dwellings in which only seronegative dogs were identified. Associations between variables were expressed as odds ratios (OR and their respective 95% confidence intervals (95%CI estimated using multivariate logistic regression. RESULTS: Dwellings with a history of dogs removed by the visceral leishmaniasis control program in the last 12 months had five-fold higher odds of having at least one seropositive dog as compared with dwellings having no history of dog removal (OR = 5.19; 95%CI = 3.20-8.42. Dwellings with cats had 58% increased odds of dog infection as compared with those having no cats (OR = 1.58; 95%CI = 1.01-2.47. CONCLUSIONS: Identification of factors associated with canine visceral leishmaniasis might be used for the delimitation of areas of higher risk for human visceral leishmaniasis, since infection in dogs generally precedes the appearance of human cases.

Asymmetrical Competition between Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae Coexisting in Breeding Sites

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Juan C. Santana-Martínez

2017-10-01

Full Text Available Aedes aegypti and Culex quinquefasciatus are mosquito vectors for several tropical diseases that represent a current public health problem. The ecological requirements for each species are different, however, both species show high biological adaptability, which promotes their coexistence in the same breeding sites. The purpose of this study was to assess the effect of larval association between Ae. aegypti and Cx. quinquefasciatus under different laboratory conditions of food supply and temperature, and under field simulated conditions like peridomestic containers. Our findings showed that under field simulated conditions there was no asymmetrical competition in mixed cultures with the different Cx. quinquefasciatus/Ae. aegypti ratios tested. However, under laboratory conditions in which different doses of food supply were evaluated, it was observed that competition between the two species takes place. Larval coexistence under food scarcity conditions (0.95 mg/larva showed that Ae. aegypti had a greater adult emergence than Cx. quinquefasciatus and was capable of depriving Cx. quinquefasciatus of the food needed to complete metamorphosis. In an intermediate dose of food (1.9 mg/larva, the dry weight of Cx. quinquefasciatus adults decreased, and their larval development time increased when Cx. quinquefasciatus/Ae. aegypti ratio was low. Also, a temperature effect was assessed demonstrating that Cx. quinquefasciatus was more vulnerable to changes in temperature. We suggest that Ae. aegypti is more successful in exploiting microhabitats when food is scarce, due to its scrape active feeding habitats and fast larval development times. Therefore, in conditions of food paucity both species will compete, and Ae. aegypti larvae will prevail.

Potential role of masting by introduced bamboos in deer mice (Peromyscus maniculatus population irruptions holds public health consequences.

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Melissa C Smith

Full Text Available We hypothesized that the ongoing naturalization of frost/shade tolerant Asian bamboos in North America could cause environmental consequences involving introduced bamboos, native rodents and ultimately humans. More specifically, we asked whether the eventual masting by an abundant leptomorphic ("running" bamboo within Pacific Northwest coniferous forests could produce a temporary surfeit of food capable of driving a population irruption of a common native seed predator, the deer mouse (Peromyscus maniculatus, a hantavirus carrier. Single-choice and cafeteria-style feeding trials were conducted for deer mice with seeds of two bamboo species (Bambusa distegia and Yushania brevipaniculata, wheat, Pinus ponderosa, and native mixed diets compared to rodent laboratory feed. Adult deer mice consumed bamboo seeds as readily as they consumed native seeds. In the cafeteria-style feeding trials, Y. brevipaniculata seeds were consumed at the same rate as native seeds but more frequently than wheat seeds or rodent laboratory feed. Females produced a median litter of 4 pups on a bamboo diet. Given the ability of deer mice to reproduce frequently whenever food is abundant, we employed our feeding trial results in a modified Rosenzweig-MacArthur consumer-resource model to project the population-level response of deer mice to a suddenly available/rapidly depleted supply of bamboo seeds. The simulations predict rodent population irruptions and declines similar to reported cycles involving Asian and South American rodents but unprecedented in deer mice. Following depletion of a mast seed supply, the incidence of Sin Nombre Virus (SNV transmission to humans could subsequently rise with dispersal of the peridomestic deer mice into nearby human settlements seeking food.

Oral ingestion of transgenic RIDL Ae. aegypti larvae has no negative effect on two predator Toxorhynchites species.

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Oreenaiza Nordin

Full Text Available Dengue is the most important mosquito-borne viral disease. No specific treatment or vaccine is currently available; traditional vector control methods can rarely achieve adequate control. Recently, the RIDL (Release of Insect carrying Dominant Lethality approach has been developed, based on the sterile insect technique, in which genetically engineered 'sterile' homozygous RIDL male insects are released to mate wild females; the offspring inherit a copy of the RIDL construct and die. A RIDL strain of the dengue mosquito, Aedes aegypti, OX513A, expresses a fluorescent marker gene for identification (DsRed2 and a protein (tTAV that causes the offspring to die. We examined whether these proteins could adversely affect predators that may feed on the insect. Aedes aegypti is a peri-domestic mosquito that typically breeds in small, rain-water-filled containers and has no specific predators. Toxorhynchites larvae feed on small aquatic organisms and are easily reared in the laboratory where they can be fed exclusively on mosquito larvae. To evaluate the effect of a predator feeding on a diet of RIDL insects, OX513A Ae. aegypti larvae were fed to two different species of Toxorhynchites (Tx. splendens and Tx. amboinensis and effects on life table parameters of all life stages were compared to being fed on wild type larvae. No significant negative effect was observed on any life table parameter studied; this outcome and the benign nature of the expressed proteins (tTAV and DsRed2 indicate that Ae. aegypti OX513A RIDL strain is unlikely to have any adverse effects on predators in the environment.

A molecular survey of Rickettsia felis in fleas from cats and dogs in Sicily (Southern Italy.

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Elisabetta Giudice

Full Text Available Rickettsia felis, the agent of flea-borne spotted fever, has a cosmopolitan distribution. Its pathogenic role in humans has been demonstrated through molecular and serologic tests in several cases. The cat flea (Ctenocephalides felis is considered the main reservoir and the biological vector. The aim of this study was to assess the presence and occurrence of R. felis in fleas collected from dogs and cats in various sites of Palermo (Sicily. Between August and October 2012, 134 fleas were collected from 42 animals: 37 fleas from 13 dogs and 97 fleas from 29 cats. Two species of fleas were identified: 132 Ctenocephalides felis (98.51% collected on all animals and only two C. canis (1.49% on one dog. Out of 132 C. felis, 34 (25.76%, 12 from dogs (32.43% and 22 (22.68% from cats, were positive for R. felis DNA by a polymerase chain reaction (PCR, confirmed by sequencing. The only two C. canis fleas were negative. About half of examined animals (47.62%, 20/42 were infested with at least one infected flea; in particular 46.15% of dogs (6/13 and 48.28% of cats (14/29. It seems that in the Palermo district there is a peri-domestic cycle, with a relatively high prevalence of R. felis infection in the cat flea, an insect widely diffused in home environments and which can frequently bite humans. The results also suggest that R. felis should be considered in the human differential diagnosis of any spotted-like fever or febrile illness without a clear source of infection in Sicily, especially if the patient is known to have been exposed to flea bites.

Domestic and environmental factors of chikungunya-affected families in Thiruvananthapuram (Rural district of Kerala, India

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T S Anish

2011-01-01

Full Text Available Background: The world is experiencing a pandemic of chikungunya which has swept across Indian Ocean and the Indian subcontinent. Kerala the southernmost state of India was affected by the chikungunya epidemic twice, first in 2006 and then in 2007. Kerala has got geography and climate which are highly favorable for the breeding of Aedes albopictus, the suspected vector. Aim: The aim of the study was to highlight the various domestic and environmental factors of the families affected by chikungunya in 2007 in Thiruvananthapuram district (rural of Kerala. Settings and design: This is a cross-sectional survey conducted in Thiruvananthapuram (rural district during November 2007. Materials and Methods : Samples were selected from field area under three Primary Health Centers. These areas represent the three terrains of the district namely the highland, midland, and lowland. The sample size was estimated to be 134 houses from each study area. The field area of health workers was selected as clusters and six subcenters from each primary health center were randomly selected (lot method. Results and Conclusions: The proportion of population affected by chikungunya fever is 39.9% (38.9-40.9%. The investigators observed water holding containers in the peri-domestic area of 95.6% of the houses. According to regression (binary logistic analysis, the area of residence [adjusted odds ratio (OR = 8.01 (6.06-14.60], residing in a non-remote area [adjusted OR=0.25 (0.16-0.38], perceived mosquito menace [adjusted OR=3.07 (2.31-4.64], and containers/tires outside the house [adjusted OR=5.61 (2.74-27.58] were the independent predictors of the occurrence of chikungunya in households.

High Prevalence of West Nile Virus in Domestic Birds and Detection in 2 New Mosquito Species in Madagascar.

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Maquart, Marianne; Boyer, Sébastien; Rakotoharinome, Vincent Michel; Ravaomanana, Julie; Tantely, Michael Luciano; Heraud, Jean-Michel; Cardinale, Eric

2016-01-01

West Nile virus is an arthropod-borne zoonosis transmitted by a large number of mosquito species, and birds play a key role as reservoir of the virus. Its distribution is largely widespread over Africa, Asia, the Americas and Europe. Since 1978, it has frequently been reported in Madagascar. Studies described a high seroprevalence level of the virus in humans in different areas of the island and a human fatal case of WNV infection was reported in 2011. Despite these reports, the epidemiology of WNV in Madagascar, in particular, viral circulation remains unclear. To explore the transmission of WNV in two rural human populations of Madagascar, we investigated local mosquitoes and poultry for evidence of current infections, and determined seroprevalence of candidate sentinel species among the local poultry. These 2 areas are close to lakes where domestic birds, migratory wild birds and humans coexist. Serological analysis revealed WNV antibodies in domestic birds (duck, chicken, goose, turkey and guinea fowl) sampled in both districts (Antsalova 29.4% and Mitsinjo 16.7%). West Nile virus nucleic acid was detected in one chicken and in 8 pools of mosquitoes including 2 mosquito species (Aedeomyia madagascarica and Anopheles pauliani) that have not been previously described as candidate vectors for WNV. Molecular analysis of WNV isolates showed that all viruses detected were part of the lineage 2 that is mainly distributed in Africa, and were most closely matched by the previous Malagasy strains isolated in 1988. Our study showed that WNV circulates in Madagascar amongst domestic birds and mosquitoes, and highlights the utility of poultry as a surveillance tool to detect WNV transmission in a peri-domestic setting.

Population dynamics of Glossina fuscipes fuscipes on Buvuma Island, Lake Victoria, Uganda

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Ogwal, L.M.; Kangwagye, T.N.

1990-01-01

A survey made of Buvuma Island to establish the incidence, distribution and population dynamics of tsetse flies showed that Glossina fuscipes fuscipes Newstead was the most abundant species. This species occurred in the southeastern, western and northern parts of the island. Although the fly is both riverine and peridomestic in its habits, the survey revealed that its population was concentrated mainly within a distance of about 2 km from the lake shores around houses, in banana plantations, at forest edges and roadsides, in fishing villages and ports of call, on grazing grounds and at water collection points. Studies of the population dynamics revealed seasonal variations in the abundance of the species, with a peak during the main dry season, i.e. in the months of January and February. The breeding peak was reached during the minor rainy season. Trap catches were highest in fishing villages and ports of call, followed in decreasing order by catches at forest edge and roadside locations, at water collection points, around houses, in banana plantations and on grazing grounds. It appears that the fishing villages and ports of call were possibly the most suitable breeding grounds. The efficiency of the traps was reflected in the fact that G. f. fuscipes populations were reduced by up to 95% in Tome and 90% in the Bulopa-Walwanda and Lwenyanja villages. Many puparia were also found on the sandy beaches around fishing villages and ports of call. There was evidence of fly movement between the islands and the mainland, indicating that, although geographically isolated, Buvuma Island is not isolated from the mainland in terms of tsetse fly movement. (author). 21 refs, 5 figs, 1 tab

Challenges posed by tick-borne rickettsiae: eco-epidemiology and public health implications.

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Eremeeva, Marina E; Dasch, Gregory A

2015-01-01

Rickettsiae are obligately intracellular bacteria that are transmitted to vertebrates by a variety of arthropod vectors, primarily by fleas and ticks. Once transmitted or experimentally inoculated into susceptible mammals, some rickettsiae may cause febrile illness of different morbidity and mortality, and which can manifest with different types of exhanthems in humans. However, most rickettsiae circulate in diverse sylvatic or peridomestic reservoirs without having obvious impacts on their vertebrate hosts or affecting humans. We have analyzed the key features of tick-borne maintenance of rickettsiae, which may provide a deeper basis for understanding those complex invertebrate interactions and strategies that have permitted survival and circulation of divergent rickettsiae in nature. Rickettsiae are found in association with a wide range of hard and soft ticks, which feed on very different species of large and small animals. Maintenance of rickettsiae in these vector systems is driven by both vertical and horizontal transmission strategies, but some species of Rickettsia are also known to cause detrimental effects on their arthropod vectors. Contrary to common belief, the role of vertebrate animal hosts in maintenance of rickettsiae is very incompletely understood. Some clearly play only the essential role of providing a blood meal to the tick while other hosts may supply crucial supplemental functions for effective agent transmission by the vectors. This review summarizes the importance of some recent findings with known and new vectors that afford an improved understanding of the eco-epidemiology of rickettsiae; the public health implications of that information for rickettsial diseases are also described. Special attention is paid to the co-circulation of different species and genotypes of rickettsiae within the same endemic areas and how these observations may influence, correctly or incorrectly, trends, and conclusions drawn from the surveillance of

Human exposure to anopheline mosquitoes occurs primarily indoors, even for users of insecticide-treated nets in Luangwa Valley, South-east Zambia

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Seyoum Aklilu

2012-05-01

Full Text Available Abstract Background Current front line malaria vector control methods such as indoor residual spraying (IRS and long-lasting insecticidal nets (LLINs, rely upon the preference of many primary vectors to feed and/or rest inside human habitations where they can be targeted with domestically-applied insecticidal products. We studied the human biting behaviour of the malaria vector Anopheles funestus Giles and the potential malaria vector Anopheles quadriannulatus Theobald in Luangwa valley, south-east Zambia. Methods Mosquitoes were collected by human landing catch in blocks of houses with either combined use of deltamethrin-based IRS and LLINs or LLINs alone. Human behaviour data were collected to estimate how much exposure to mosquito bites indoors and outdoors occurred at various times of the night for LLIN users and non-users. Results Anopheles funestus and An. quadriannulatus did not show preference to bite either indoors or outdoors: the proportions [95% confidence interval] caught indoors were 0.586 [0.303, 0.821] and 0.624 [0.324, 0.852], respectively. However, the overwhelming majority of both species were caught at times when most people are indoors. The proportion of mosquitoes caught at a time when most people are indoors were 0.981 [0.881, 0.997] and 0.897 [0.731, 0.965], respectively, so the proportion of human exposure to both species occuring indoors was high for individuals lacking LLINs (An. funestus: 0.983 and An. quadriannulatus: 0.970, respectively. While LLIN users were better protected, more than half of their exposure was nevertheless estimated to occur indoors (An. funestus: 0.570 and An. quadriannulatus: 0.584. Conclusions The proportion of human exposure to both An. funestus and An. quadriannulatus occuring indoors was high in the area and hence both species might be responsive to further peri-domestic measures if these mosquitoes are susceptible to insecticidal products.

Rickettsia bellii, Rickettsia amblyommii, and Laguna Negra hantavirus in an Indian reserve in the Brazilian Amazon.

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de Barros Lopes, Lívia; Guterres, Alexandro; Rozental, Tatiana; Carvalho de Oliveira, Renata; Mares-Guia, Maria Angélica; Fernandes, Jorlan; Figueredo, José Ferreira; Anschau, Inês; de Jesus, Sebastião; V Almeida, Ana Beatriz M; Cristina da Silva, Valéria; Gomes de Melo Via, Alba Valéria; Bonvicino, Cibele Rodrigues; D'Andrea, Paulo Sérgio; Barreira, Jairo Dias; Sampaio de Lemos, Elba Regina

2014-04-17

The purpose of this study was to identify the presence of rickettsia and hantavirus in wild rodents and arthropods in response to an outbreak of acute unidentified febrile illness among Indians in the Halataikwa Indian Reserve, northwest of the Mato Grosso state, in the Brazilian Amazon. Where previously surveillance data showed serologic evidence of rickettsia and hantavirus human infection. The arthropods were collected from the healthy Indian population and by flagging vegetation in grassland or woodland along the peridomestic environment of the Indian reserve. Wild rodents were live-trapped in an area bordering the reserve limits, due the impossibility of capturing wild animals in the Indian reserve. The wild rodents were identified based on external and cranial morphology and karyotype. DNA was extracted from spleen or liver samples of rodents and from invertebrate (tick and louse) pools, and the molecular characterization of the rickettsia was through PCR and DNA sequencing of fragments of two rickettsial genes (gltA and ompA). In relation to hantavirus, rodent serum samples were serologically screened by IgG ELISA using the Araraquara-N antigen and total RNA was extracted from lung samples of IgG-positive rodents. The amplification of the complete S segment was performed. A total of 153 wild rodents, 121 louse, and 36 tick specimens were collected in 2010. Laguna Negra hantavirus was identified in Calomys callidus rodents and Rickettsia bellii, Rickettsia amblyommii were identified in Amblyomma cajennense ticks. Zoonotic diseases such as HCPS and spotted fever rickettsiosis are a public health threat and should be considered in outbreaks and acute febrile illnesses among Indian populations. The presence of the genome of rickettsias and hantavirus in animals in this Indian reserve reinforces the need to include these infectious agents in outbreak investigations of febrile cases in Indian populations.

High Leptospira Diversity in Animals and Humans Complicates the Search for Common Reservoirs of Human Disease in Rural Ecuador.

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Barragan, Veronica; Chiriboga, Jorge; Miller, Erin; Olivas, Sonora; Birdsell, Dawn; Hepp, Crystal; Hornstra, Heidie; Schupp, James M; Morales, Melba; Gonzalez, Manuel; Reyes, Soraya; de la Cruz, Carmen; Keim, Paul; Hartskeerl, Rudy; Trueba, Gabriel; Pearson, Talima

2016-09-01

Leptospirosis is a zoonotic disease responsible for high morbidity around the world, especially in tropical and low income countries. Rats are thought to be the main vector of human leptospirosis in urban settings. However, differences between urban and low-income rural communities provide additional insights into the epidemiology of the disease. Our study was conducted in two low-income rural communities near the coast of Ecuador. We detected and characterized infectious leptospira DNA in a wide variety of samples using new real time quantitative PCR assays and amplicon sequencing. We detected infectious leptospira in a high percentage of febrile patients (14.7%). In contrast to previous studies on leptospirosis risk factors, higher positivity was not found in rats (3.0%) but rather in cows (35.8%) and pigs (21.1%). Six leptospira species were identified (L. borgpetersenii, L kirschnerii, L santarosai, L. interrogans, L noguchii, and an intermediate species within the L. licerasiae and L. wolffii clade) and no significant differences in the species of leptospira present in each animal species was detected (χ2 = 9.89, adj.p-value = 0.27). A large portion of the world's human population lives in low-income, rural communities, however, there is limited information about leptospirosis transmission dynamics in these settings. In these areas, exposure to peridomestic livestock is particularly common and high prevalence of infectious leptospira in cows and pigs suggest that they may be the most important reservoir for human transmission. Genotyping clinical samples show that multiple species of leptospira are involved in human disease. As these genotypes were also detected in samples from a variety of animals, genotype data must be used in conjunction with epidemiological data to provide evidence of transmission and the importance of different potential leptospirosis reservoirs.

Unraveling Host-Vector-Arbovirus Interactions by Two-Gene High Resolution Melting Mosquito Bloodmeal Analysis in a Kenyan Wildlife-Livestock Interface.

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David Omondi

Full Text Available The blood-feeding patterns of mosquitoes are directly linked to the spread of pathogens that they transmit. Efficient identification of arthropod vector bloodmeal hosts can identify the diversity of vertebrate species potentially involved in disease transmission cycles. While molecular bloodmeal analyses rely on sequencing of cytochrome b (cyt b or cytochrome oxidase 1 gene PCR products, recently developed bloodmeal host identification based on high resolution melting (HRM analyses of cyt b PCR products is more cost-effective. To resolve the diverse vertebrate hosts that mosquitoes may potentially feed on in sub-Saharan Africa, we utilized HRM profiles of both cyt b and 16S ribosomal RNA genes. Among 445 blood-fed Aedeomyia, Aedes, Anopheles, Culex, Mansonia, and Mimomyia mosquitoes from Kenya's Lake Victoria and Lake Baringo regions where many mosquito-transmitted pathogens are endemic, we identified 33 bloodmeal hosts including humans, eight domestic animal species, six peridomestic animal species and 18 wildlife species. This resolution of vertebrate host species was only possible by comparing profiles of both cyt b and 16S markers, as melting profiles of some pairs of species were similar for either marker but not both. We identified mixed bloodmeals in a Culex pipiens from Mbita that had fed on a goat and a human and in two Mansonia africana mosquitoes from Baringo that each had fed on a rodent (Arvicanthis niloticus in addition to a human or baboon. We further detected Sindbis and Bunyamwera viruses in blood-fed mosquito homogenates by Vero cell culture and RT-PCR in Culex, Aedeomyia, Anopheles and Mansonia mosquitoes from Baringo that had fed on humans and livestock. The observed mosquito feeding on both arbovirus amplifying hosts (including sheep and goats and possible arbovirus reservoirs (birds, porcupine, baboons, rodents informs arbovirus disease epidemiology and vector control strategies.

Elevated dry-season malaria prevalence associated with fine-scale spatial patterns of environmental risk: a case-control study of children in rural Malawi.

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Townes, Lindsay R; Mwandama, Dyson; Mathanga, Don P; Wilson, Mark L

2013-11-11

Understanding the role of local environmental risk factors for malaria in holo-endemic, poverty-stricken settings will be critical to more effectively implement- interventions aimed at eventual elimination. Household-level environmental drivers of malaria risk during the dry season were investigated in rural southern Malawi among children Authority (TA) regions dominated by small-scale agriculture. Ten villages were randomly selected from TA Sitola (n = 6) and Nsamala (n = 4). Within each village, during June to August 2011, a census was conducted of all households with children under-five and recorded their locations with a geographic position system (GPS) device. At each participating house, a nurse administered a malaria rapid diagnostic test (RDT) to children under five years of age, and a questionnaire to parents. Environmental data were collected for each house, including land cover within 50-m radius. Variables found to be significantly associated with P. falciparum infection status in bivariate analysis were included in generalized linear models, including multivariate logistic regression (MLR) and multi-level multivariate logistic regression (MLLR). Spatial clustering of RDT status, environmental factors, and Pearson residuals from MLR and MLLR were analysed using the Getis-Ord Gi* statistic. Of 390 children enrolled from six villages in Sitola (n = 162) and four villages in Nsamala (n = 228), 45.6% tested positive (n = 178) for Plasmodium infection by RDT. The MLLR modelled the statistical relationship of Plasmodium positives and household proximity to agriculture ( 2.58, p < 0.01) predominantly within TA Sitola, while residuals from MLLR showed no such clustering. This study provides evidence for significant, dry-season heterogeneity of malaria prevalence strongly linked to peridomestic land use, and particularly of elevated risk associated with nearby crop production.

Enhanced Replication of Virulent Newcastle Disease Virus in Chicken Macrophages Is due to Polarized Activation of Cells by Inhibition of TLR7.

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Zhang, Pingze; Ding, Zhuang; Liu, Xinxin; Chen, Yanyu; Li, Junjiao; Tao, Zhi; Fei, Yidong; Xue, Cong; Qian, Jing; Wang, Xueli; Li, Qingmei; Stoeger, Tobias; Chen, Jianjun; Bi, Yuhai; Yin, Renfu

2018-01-01

Newcastle disease (ND), caused by infections with virulent strains of Newcastle disease virus (NDV), is one of the most important infectious disease affecting wild, peridomestic, and domestic birds worldwide. Vaccines constructed from live, low-virulence (lentogenic) viruses are the most accepted prevention and control strategies for combating ND in poultry across the globe. Avian macrophages are one of the first cell lines of defense against microbial infection, responding to signals in the microenvironment. Although macrophages are considered to be one of the main target cells for NDV infection in vivo , very little is known about the ability of NDV to infect chicken macrophages, and virulence mechanisms of NDV as well as the polarized activation patterns of macrophages and correlation with viral infection and replication. In the present study, a cell culture model (chicken bone marrow macrophage cell line HD11) and three different virulence and genotypes of NDV (including class II virulent NA-1, class II lentogenic LaSota, and class I lentogenic F55) were used to solve the above underlying questions. Our data indicated that all three NDV strains had similar replication rates during the early stages of infection. Virulent NDV titers were shown to increase compared to the other lentogenic strains, and this growth was associated with a strong upregulation of both pro-inflammatory M1-like markers/cytokines and anti-inflammatory M2-like markers/cytokines in chicken macrophages. Virulent NDV was found to block toll-like receptor (TLR) 7 expression, inducing higher expression of type I interferons in chicken macrophages at the late stage of viral infection. Only virulent NDV replication can be inhibited by pretreatment with TLR7 ligand. Overall, this study demonstrated that virulent NDV activates a M1-/M2-like mixed polarized activation of chicken macrophages by inhibition of TLR7, resulting in enhanced replication compared to lentogenic viruses.

Pioneer study of population genetics of Rhodnius ecuadoriensis (Hemiptera: Reduviidae) from the central coastand southern Andean regions of Ecuador.

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Villacís, Anita G; Marcet, Paula L; Yumiseva, César A; Dotson, Ellen M; Tibayrenc, Michel; Brenière, Simone Frédérique; Grijalva, Mario J

2017-09-01

Effective control of Chagas disease vector populations requires a good understanding of the epidemiological components, including a reliable analysis of the genetic structure of vector populations. Rhodnius ecuadoriensis is the most widespread vector of Chagas disease in Ecuador, occupying domestic, peridomestic and sylvatic habitats. It is widely distributed in the central coast and southern highlands regions of Ecuador, two very different regions in terms of bio-geographical characteristics. To evaluate the genetic relationship among R. ecuadoriensis populations in these two regions, we analyzed genetic variability at two microsatellite loci for 326 specimens (n=122 in Manabí and n=204 in Loja) and the mitochondrial cytochrome b gene (Cyt b) sequences for 174 individuals collected in the two provinces (n=73 and=101 in Manabí and Loja respectively). The individual samples were grouped in populations according to their community of origin. A few populations presented positive F IS, possible due to Wahlund effect. Significant pairwise differentiation was detected between populations within each province for both genetic markers, and the isolation by distance model was significant for these populations. Microsatellite markers showed significant genetic differentiation between the populations of the two provinces. The partial sequences of the Cyt b gene (578bp) identified a total of 34 haplotypes among 174 specimens sequenced, which translated into high haplotype diversity (Hd=0.929). The haplotype distribution differed among provinces (significant Fisher's exact test). Overall, the genetic differentiation of R. ecuadoriensis between provinces detected in this study is consistent with the biological and phenotypic differences previously observed between Manabí and Loja populations. The current phylogenetic analysis evidenced the monophyly of the populations of R. ecuadoriensis within the R. pallescens species complex; R. pallescens and R. colombiensis were more

Assessment of Domestic Goats as Models for Experimental and Natural Infection with the North American Isolate of Rickettsia slovaca.

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Lukovsky-Akhsanov, Nicole; Keating, M Kelly; Spivey, Pamela; Lathrop, George W; Powell, Nathaniel; Levin, Michael L

2016-01-01

Rickettsia slovaca is a tick-borne human pathogen that is associated with scalp eschars and neck lymphadenopathy known as tick-borne lymphadenopathy (TIBOLA) or Dermacentor-borne necrosis erythema and lymphadenopathy (DEBONEL). Originally, R. slovaca was described in Eastern Europe, but since recognition of its pathogenicity, human cases have been reported throughout Europe. European vertebrate reservoirs of R. slovaca remain unknown, but feral swine and domestic goats have been found infected or seropositive for this pathogen. Recently, a rickettsial pathogen identical to R. slovaca was identified in, and isolated from, the American dog tick, Dermacentor variabilis. In previous experimental studies, this organism was found infectious to guinea pigs and transovarially transmissible in ticks. In this study, domestic goats (Capra hircus) were experimentally inoculated with the North American isolate of this R. slovaca-like agent to assess their reservoir competence-the ability to acquire the pathogens and maintain transmission between infected and uninfected ticks. Goats were susceptible to infection as demonstrated by detection of the pathogen in skin biopsies and multiple internal tissues, but the only clinical sign of illness was transient fever noted in three out of four goats, and reactive lymphoid hyperplasia. On average, less than 5% of uninfected ticks acquired the pathogen while feeding upon infected goats. Although domestic goats are susceptible to the newly described North American isolate of R. slovaca, they are likely to play a minor role in the natural transmission cycle of this pathogen. Our results suggest that goats do not propagate the North American isolate of R. slovaca in peridomestic environments and clinical diagnosis of infection could be difficult due to the brevity and mildness of clinical signs. Further research is needed to elucidate the natural transmission cycle of R. slovaca both in Europe and North America, as well as to identify a

Molecular detection of Rickettsia typhi in cats and fleas.

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Maria Mercedes Nogueras

Full Text Available BACKGROUND: Rickettsiatyphi is the etiological agent of murine typhus (MT, a disease transmitted by two cycles: rat-flea-rat, and peridomestic cycle. Murine typhus is often misdiagnosed and underreported. A correct diagnosis is important because MT can cause severe illness and death. Our previous seroprevalence results pointed to presence of human R. typhi infection in our region; however, no clinical case has been reported. Although cats have been related to MT, no naturally infected cat has been described. The aim of the study is to confirm the existence of R. typhi in our location analyzing its presence in cats and fleas. METHODOLOGY/PRINCIPAL FINDINGS: 221 cats and 80 fleas were collected from Veterinary clinics, shelters, and the street (2001-2009. Variables surveyed were: date of collection, age, sex, municipality, living place, outdoor activities, demographic area, healthy status, contact with animals, and ectoparasite infestation. IgG against R. typhi were evaluated by indirect immunofluorescence assay. Molecular detection in cats and fleas was performed by real-time PCR. Cultures were performed in those cats with positive molecular detection. Statistical analysis was carried out using SPSS. A p < 0.05 was considered significant. Thirty-five (15.8% cats were seropositive. There were no significant associations among seropositivity and any variables. R. typhi was detected in 5 blood and 2 cultures. High titres and molecular detection were observed in stray cats and pets, as well as in spring and winter. All fleas were Ctenocephalides felis. R. typhi was detected in 44 fleas (55%, from shelters and pets. Co-infection with R. felis was observed. CONCLUSIONS: Although no clinical case has been described in this area, the presence of R. typhi in cats and fleas is demonstrated. Moreover, a considerable percentage of those animals lived in households. To our knowledge, this is the first time R. typhi is detected in naturally infected cats.

Malaria: Knowledge and prevention practices among school adolescents in a coastal community in Calabar, Nigeria

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Gyuse, Abraham N.; Etokidem, Aniekan J.

2010-01-01

ABSTRACT Background Malaria prevention and treatment constitute an unbearable economic burden to most African countries, especially south of the Sahara, where about 500 million cases occur annually. The problem of malaria among adolescents has largely been overshadowed by the huge burden of the disease among young children. Attention to malaria among adolescents has also been diverted by the huge burden of HIV/AIDS among adolescents. Some surveys reveal a lack of knowledge and many misconceptions about the transmission and treatment of malaria, which could adversely affect malaria control measures and antimalarial therapy. Such a knowledge gap could have an adverse effect on school children, who could be used as change agents and as role models for their siblings and peers in the malaria control strategy. Objectives To determine the malaria prevention practices of school adolescents in the coastal community of Calabar, Nigeria. Method This was a cross-sectional survey involving secondary schools in southern Calabar. Four hundred adolescents were randomly selected from the 4565 learners in 5 out of 17 secondary schools in southern Calabar, Cross River State, Nigeria. A self-administered, semi-structured questionnaire was administered to the respondents. Results Most respondents (77.5%) were aware that the vector transmits the malaria parasite through biting. Fewer respondents would prevent malaria attacks by clearing the vegetation in the peri-domestic environment (13.5%), filling up potholes (16.9%), opening up drainage (11%), using insecticide-treated nets (25.7%) or using antimalarial drugs (11.2%). Less than one-tenth (8%) would use various other methods such as not accepting unscreened blood, while only 11% obtained the information from their teachers. Conclusion The study identified knowledge gaps among school children. There is a need to empower teachers with information about the cause of malaria and prevention strategies.

Community-based control of the brown dog tick in a region with high rates of Rocky Mountain spotted fever, 2012-2013.

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Drexler, Naomi; Miller, Mark; Gerding, Justin; Todd, Suzanne; Adams, Laura; Dahlgren, F Scott; Bryant, Nelva; Weis, Erica; Herrick, Kristen; Francies, Jessica; Komatsu, Kenneth; Piontkowski, Stephen; Velascosoltero, Jose; Shelhamer, Timothy; Hamilton, Brian; Eribes, Carmen; Brock, Anita; Sneezy, Patsy; Goseyun, Cye; Bendle, Harty; Hovet, Regina; Williams, Velda; Massung, Robert; McQuiston, Jennifer H

2014-01-01

Rocky Mountain spotted fever (RMSF) transmitted by the brown dog tick (Rhipicephalus sanguineus sensu lato) has emerged as a significant public health risk on American Indian reservations in eastern Arizona. During 2003-2012, more than 250 RMSF cases and 19 deaths were documented among Arizona's American Indian population. The high case fatality rate makes community-level interventions aimed at rapid and sustained reduction of ticks urgent. Beginning in 2012, a two year pilot integrated tick prevention campaign called the RMSF Rodeo was launched in a ∼ 600-home tribal community with high rates of RMSF. During year one, long-acting tick collars were placed on all dogs in the community, environmental acaricides were applied to yards monthly, and animal care practices such as spay and neuter and proper tethering procedures were encouraged. Tick levels, indicated by visible inspection of dogs, tick traps and homeowner reports were used to monitor tick presence and evaluate the efficacy of interventions throughout the project. By the end of year one, <1% of dogs in the RMSF Rodeo community had visible tick infestations five months after the project was started, compared to 64% of dogs in Non-Rodeo communities, and environmental tick levels were reduced below detectable levels. The second year of the project focused on use of the long-acting collar alone and achieved sustained tick control with fewer than 3% of dogs in the RMSF Rodeo community with visible tick infestations by the end of the second year. Homeowner reports of tick activity in the domestic and peridomestic setting showed similar decreases in tick activity compared to the non-project communities. Expansion of this successful project to other areas with Rhipicephalus-transmitted RMSF has the potential to reduce brown dog tick infestations and save human lives.

Community-based control of the brown dog tick in a region with high rates of Rocky Mountain spotted fever, 2012-2013.

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Naomi Drexler

Full Text Available Rocky Mountain spotted fever (RMSF transmitted by the brown dog tick (Rhipicephalus sanguineus sensu lato has emerged as a significant public health risk on American Indian reservations in eastern Arizona. During 2003-2012, more than 250 RMSF cases and 19 deaths were documented among Arizona's American Indian population. The high case fatality rate makes community-level interventions aimed at rapid and sustained reduction of ticks urgent. Beginning in 2012, a two year pilot integrated tick prevention campaign called the RMSF Rodeo was launched in a ∼ 600-home tribal community with high rates of RMSF. During year one, long-acting tick collars were placed on all dogs in the community, environmental acaricides were applied to yards monthly, and animal care practices such as spay and neuter and proper tethering procedures were encouraged. Tick levels, indicated by visible inspection of dogs, tick traps and homeowner reports were used to monitor tick presence and evaluate the efficacy of interventions throughout the project. By the end of year one, <1% of dogs in the RMSF Rodeo community had visible tick infestations five months after the project was started, compared to 64% of dogs in Non-Rodeo communities, and environmental tick levels were reduced below detectable levels. The second year of the project focused on use of the long-acting collar alone and achieved sustained tick control with fewer than 3% of dogs in the RMSF Rodeo community with visible tick infestations by the end of the second year. Homeowner reports of tick activity in the domestic and peridomestic setting showed similar decreases in tick activity compared to the non-project communities. Expansion of this successful project to other areas with Rhipicephalus-transmitted RMSF has the potential to reduce brown dog tick infestations and save human lives.

Notes from the Field: Community-Based Prevention of Rocky Mountain Spotted Fever - Sonora, Mexico, 2016.

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Straily, Anne; Drexler, Naomi; Cruz-Loustaunau, Denica; Paddock, Christopher D; Alvarez-Hernandez, Gerardo

2016-11-25

Rocky Mountain spotted fever (RMSF), a life-threatening tickborne zoonosis caused by Rickettsia rickettsii, is a reemerging disease in Mexico (1,2). R. rickettsii is an intracellular bacterium that infects vascular endothelium and can cause multisystem organ failure and death in the absence of timely administration of a tetracycline-class antibiotic, typically doxycycline. Epidemic RMSF, as described in parts of Arizona and Mexico, is associated with massive local infestations of the brown dog tick (Rhiphicephalus sanguineus sensu lato) on domestic dogs and in peridomestic settings that result in high rates of human exposure; for example, during 2003-2012, in Arizona the incidence of RMSF in the three most highly affected communities was 150 times the U.S. national average (3,4). In 2015, the Mexico Ministry of Health (MOH) declared an epidemiologic emergency because of high and sustained rates of RMSF in several states in northern Mexico, including the state of Sonora. During 2004-2015, a total of 1,129 cases and 188 RMSF deaths were reported from Sonora (Sonora MOH, unpublished data, 2016). During 2009-2015, one impoverished community (community A) in Sonora reported 56 cases of RMSF involving children and adolescents, with a case-fatality rate of 40% (Sonora MOH, unpublished data, 2016). Poverty and lack of timely access to health services are risk factors for severe RMSF. Children are especially vulnerable to infection, because they might have increased contact with dogs and spend more time playing around spaces where ticks survive (5). In Sonora, case fatality rates for children aged <10 years can be as high as 30%, which is almost four times the aggregate case-fatality rate reported for the general population of the state (8%) (2), and 10-13 times higher than the case-fatality rate described for this age group in the United States (2.4%) (6).

Community-Based Control of the Brown Dog Tick in a Region with High Rates of Rocky Mountain Spotted Fever, 2012–2013

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Drexler, Naomi; Miller, Mark; Gerding, Justin; Todd, Suzanne; Adams, Laura; Dahlgren, F. Scott; Bryant, Nelva; Weis, Erica; Herrick, Kristen; Francies, Jessica; Komatsu, Kenneth; Piontkowski, Stephen; Velascosoltero, Jose; Shelhamer, Timothy; Hamilton, Brian; Eribes, Carmen; Brock, Anita; Sneezy, Patsy; Goseyun, Cye; Bendle, Harty; Hovet, Regina; Williams, Velda; Massung, Robert; McQuiston, Jennifer H.

2014-01-01

Rocky Mountain spotted fever (RMSF) transmitted by the brown dog tick (Rhipicephalus sanguineus sensu lato) has emerged as a significant public health risk on American Indian reservations in eastern Arizona. During 2003–2012, more than 250 RMSF cases and 19 deaths were documented among Arizona's American Indian population. The high case fatality rate makes community-level interventions aimed at rapid and sustained reduction of ticks urgent. Beginning in 2012, a two year pilot integrated tick prevention campaign called the RMSF Rodeo was launched in a ∼600-home tribal community with high rates of RMSF. During year one, long-acting tick collars were placed on all dogs in the community, environmental acaricides were applied to yards monthly, and animal care practices such as spay and neuter and proper tethering procedures were encouraged. Tick levels, indicated by visible inspection of dogs, tick traps and homeowner reports were used to monitor tick presence and evaluate the efficacy of interventions throughout the project. By the end of year one, <1% of dogs in the RMSF Rodeo community had visible tick infestations five months after the project was started, compared to 64% of dogs in Non-Rodeo communities, and environmental tick levels were reduced below detectable levels. The second year of the project focused on use of the long-acting collar alone and achieved sustained tick control with fewer than 3% of dogs in the RMSF Rodeo community with visible tick infestations by the end of the second year. Homeowner reports of tick activity in the domestic and peridomestic setting showed similar decreases in tick activity compared to the non-project communities. Expansion of this successful project to other areas with Rhipicephalus-transmitted RMSF has the potential to reduce brown dog tick infestations and save human lives. PMID:25479289

Temporal Variation in the Abundance and Timing of Daily Activity of Chagas Disease Vector Triatoma gerstaeckeri (Stål, 1859) in a Natural Habitat in the Lower Rio Grande Valley, South Texas.

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Flores, A; Vitek, C; Feria-Arroyo, T P; Fredensborg, B L

2017-10-01

Chagas disease caused by Trypanosoma cruzi is a burden to millions of people in South and Central America. A sylvatic life cycle of the parasite exists in the Southern United States, but recent studies indicate an active peri-domestic life cycle of T. cruzi in Texas. The United States-Mexico border region in Texas displays areas of high poverty and sub-standard housing conditions which are important risk factors for a potential spill-over transmission to a domestic life cycle including humans. The objectives of the study were to examine short- and long-term temporal variation in vector activity and to evaluate the effect of different combinations of attractants on the capture of potential triatomine vectors. We collected local triatomine vectors (all of them identified as Triatoma gerstaeckeri) from a natural habitat in South Texas during the course of a year. The exact time of collection was recorded to examine the timing of flight activity of the triatomine vector. We also conducted a comparative study of the efficiency of 2 commonly used attractants (light and CO 2 ) and the combination of those on the capture rate of Tr. gerstaeckeri. Our study indicates a short season of dispersal of Tr. gerstaeckeri (April/May) and it suggests a unimodal distribution of activity peaking between 2 and 3 hr after sunset. Ultra-violet light served as the main attractant of Tr. gerstaeckeri while CO 2 from dry ice did not significantly contribute to the collection of vectors. The pronounced timing of activity in Tr. gerstaeckeri reported in this study contributes to our understanding of the epidemiology of T. cruzi in wildlife and its potential as a Chagas disease vector to humans in the Rio Grande Valley, South Texas.

Analysis of spatial mobility in subjects from a Dengue endemic urban locality in Morelos State, Mexico.

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Falcón-Lezama, Jorge Abelardo; Santos-Luna, René; Román-Pérez, Susana; Martínez-Vega, Ruth Aralí; Herrera-Valdez, Marco Arieli; Kuri-Morales, Ángel Fernando; Adams, Ben; Kuri-Morales, Pablo Antonio; López-Cervantes, Malaquías; Ramos-Castañeda, José

2017-01-01

Mathematical models and field data suggest that human mobility is an important driver for Dengue virus transmission. Nonetheless little is known on this matter due the lack of instruments for precise mobility quantification and study design difficulties. We carried out a cohort-nested, case-control study with 126 individuals (42 cases, 42 intradomestic controls and 42 population controls) with the goal of describing human mobility patterns of recently Dengue virus-infected subjects, and comparing them with those of non-infected subjects living in an urban endemic locality. Mobility was quantified using a GPS-data logger registering waypoints at 60-second intervals for a minimum of 15 natural days. Although absolute displacement was highly biased towards the intradomestic and peridomestic areas, occasional displacements exceeding a 100-Km radius from the center of the studied locality were recorded for all three study groups and individual displacements were recorded traveling across six states from central Mexico. Additionally, cases had a larger number of visits out of the municipality´s administrative limits when compared to intradomestic controls (cases: 10.4 versus intradomestic controls: 2.9, p = 0.0282). We were able to identify extradomestic places within and out of the locality that were independently visited by apparently non-related infected subjects, consistent with houses, working and leisure places. Results of this study show that human mobility in a small urban setting exceeded that considered by local health authority's administrative limits, and was different between recently infected and non-infected subjects living in the same household. These observations provide important insights about the role that human mobility may have in Dengue virus transmission and persistence across endemic geographic areas that need to be taken into account when planning preventive and control measures. Finally, these results are a valuable reference when setting the

Impact of container material on the development of Aedes aegypti larvae at different temperatures.

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Kumar, Gaurav; Singh, R K; Pande, Veena; Dhiman, R C

2016-01-01

Aedes aegypti, the primary vector of dengue generally breeds in intradomestic and peridomestic containers made up of different materials, i.e. plastic, iron, rubber, earthen material etc. The material of container is likely to affect the temperature of water in container with variation in environmental temperature. The present study was aimed to determine the effect of different container materials on larval development of Ae. aegypti at different temperatures. Newly hatched I instar larvae (2-4 h old) were used in the study and experiments were conducted using three different containers made up of plastic, iron and earthen material. Three replicates for each type of container at 22, 26, 30, 34, 38, 40, and 42°C were placed in environmental chamber for the development of larvae. At temperatures >22°C, 50% pupation was completed in earthen pot within 4.3±0.6 to 6.3±0.6 days followed by plastic containers (5±0 to 8±0 days) and iron containers (6±0 to 9±0 days). Developmental time for 50% pupation in the three containers differed significantly (p containers (p containers resulted in significant variations in the developmental period of larvae. More than 35°C temperature of water was found inimical for pupal development. The results revealed the variation in temperature of water in different types of containers depending on the material of container, affecting duration of larval development. As the larval development was faster in earthen pot as compared to plastic and iron containers, community should be discouraged for storing the water in earthen pots. However, in view of containers of different materials used by the community in different temperature zones in the country, further studies are required for devising area-specific preventive measures for Aedes breeding.

Hidden sylvatic foci of the main vector of Chagas disease Triatoma infestans: threats to the vector elimination campaign?

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Leonardo A Ceballos

2011-10-01

Full Text Available Establishing the sources of reinfestation after residual insecticide spraying is crucial for vector elimination programs. Triatoma infestans, traditionally considered to be limited to domestic or peridomestic (abbreviated as D/PD habitats throughout most of its range, is the target of an elimination program that has achieved limited success in the Gran Chaco region in South America.During a two-year period we conducted semi-annual searches for triatomine bugs in every D/PD site and surrounding sylvatic habitats after full-coverage spraying of pyrethroid insecticides of all houses in a well-defined rural area in northwestern Argentina. We found six low-density sylvatic foci with 24 T. infestans in fallen or standing trees located 110-2,300 m from the nearest house or infested D/PD site detected after insecticide spraying, when house infestations were rare. Analysis of two mitochondrial gene fragments of 20 sylvatic specimens confirmed their species identity as T. infestans and showed that their composite haplotypes were the same as or closely related to D/PD haplotypes. Population studies with 10 polymorphic microsatellite loci and wing geometric morphometry consistently indicated the occurrence of unrestricted gene flow between local D/PD and sylvatic populations. Mitochondrial DNA and microsatellite sibship analyses in the most abundant sylvatic colony revealed descendents from five different females. Spatial analysis showed a significant association between two sylvatic foci and the nearest D/PD bug population found before insecticide spraying.Our study shows that, despite of its high degree of domesticity, T. infestans has sylvatic colonies with normal chromatic characters (not melanic morphs highly connected to D/PD conspecifics in the Argentinean Chaco. Sylvatic habitats may provide a transient or permanent refuge after control interventions, and function as sources for D/PD reinfestation. The occurrence of sylvatic foci of T. infestans in

Genetic Characterization of Spondweni and Zika Viruses and Susceptibility of Geographically Distinct Strains of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae to Spondweni Virus.

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Andrew D Haddow

2016-10-01

Full Text Available Zika virus (ZIKV has extended its known geographic distribution to the New World and is now responsible for severe clinical complications in a subset of patients. While substantial genetic and vector susceptibility data exist for ZIKV, less is known for the closest related flavivirus, Spondweni virus (SPONV. Both ZIKV and SPONV have been known to circulate in Africa since the mid-1900s, but neither has been genetically characterized by gene and compared in parallel. Furthermore, the susceptibility of peridomestic mosquito species incriminated or suspected in the transmission of ZIKV to SPONV was unknown.In this study, two geographically distinct strains of SPONV were genetically characterized and compared to nine genetically and geographically distinct ZIKV strains. Additionally, the susceptibility of both SPONV strains was determined in three mosquito species. The open reading frame (ORF of the SPONV 1952 Nigerian Chuku strain, exhibited a nucleotide and amino acid identity of 97.8% and 99.2%, respectively, when compared to the SPONV 1954 prototype South African SA Ar 94 strain. The ORF of the SPONV Chuku strain exhibited a nucleotide and amino acid identity that ranged from 68.3% to 69.0% and 74.6% to 75.0%, respectively, when compared to nine geographically and genetically distinct strains of ZIKV. The ORF of the nine African and Asian lineage ZIKV strains exhibited limited nucleotide divergence. Aedes aegypti, Ae. albopictus and Culex quinquefasciatus susceptibility and dissemination was low or non-existent following artificial infectious blood feeding of moderate doses of both SPONV strains.SPONV and ZIKV nucleotide and amino acid divergence coupled with differences in geographic distribution, ecology and vector species support previous reports that these viruses are separate species. Furthermore, the low degree of SPONV infection or dissemination in Ae. albopictus, Ae. aegypti and Cx. quinquefasciatus following exposure to two

The development of an ivermectin-based attractive toxic sugar bait (ATSB) to target Anopheles arabiensis.

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Tenywa, Frank Chelestino; Kambagha, Athumani; Saddler, Adam; Maia, Marta Ferreira

2017-08-15

An increasing number of countries in sub-Saharan Africa are moving towards malaria-elimination, mostly thanks to successful vector control campaigns. However, elimination has proven challenging, resulting in the persistence of malaria transmission. It is now accepted that in order to eliminate malaria, new complementary vector control approaches must be developed. This study describes the development of a sugar-baited resting place containing a toxic dose of ivermectin for the control of Anopheles arabiensis. Dose response experiments were performed in insectary conditions to determine the LD90 of ivermectin against An. arabiensis. Over 95% of An. arabiensis were knocked down 48 h post-sugar feeding on 10% sucrose solutions containing 0.01% ivermectin. When investigating different juices as attractants, it was observed that An. arabiensis preferred orange, watermelon and commercial guava juice over pawpaw, tomato, mango or banana, but were most likely to feed on simple 10% sugar solution. Using recycled materials, different bait prototypes were tested to determine the best design to maximize sugar feeding. Baits that offered a resting place for the mosquito rather than just a surface to sugar feed were more likely to attract An. arabiensis to sugar feed. The optimized prototype was then placed in different locations within a screen-house, colour-coded with different food dyes, containing competing vegetation (Ricinus communis) and experimental huts where humans slept under bed nets. Around half of all the released An. arabiensis sugar fed on the sugar baits, and approximately 50% of all sugar fed mosquitoes chose the baits close to outdoor vegetation before entering the huts. Ivermectin is an effective insecticide for use in sugar baits. The design of the sugar bait can influence feeding rates and, therefore, efficacy. Sugar baits that offer a resting surface are more efficient and sugar feeding on the baits is maximized when these are placed close to peri-domestic

Bacteria stimulate hatching of yellow fever mosquito eggs.

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Loganathan Ponnusamy

Full Text Available BACKGROUND: Aedes aegypti Linnaeus is a peridomestic mosquito that lays desiccation-resistant eggs in water-filled human-made containers. Previous investigations connected egg hatching with declining dissolved oxygen (DO that is associated with bacterial growth. However, past studies failed to uncouple DO from other potential stimulatory factors and they contained little quantitative information about the microbial community; consequently, a direct role for bacteria or compounds associated with bacteria in stimulating egg hatching cannot be dismissed. METHODOLOGY/PRINCIPAL FINDINGS: Environmental factors stimulating hatch of Ae. aegypti eggs were investigated using non-sterile and sterile white oak leaf (WOL infusions and a bacterial culture composed of a mix of 14 species originally isolated from bamboo leaf infusion. In WOL infusion with active microbes, 92.4% of eggs hatched in 2-h at an average DO concentration of 2.4 ppm. A 24-h old bacterial culture with a DO concentration of 0.73 ppm also stimulated 95.2% of eggs hatch within 1-h. In contrast, only 4.0% of eggs hatched in sterile infusion, whose DO averaged 7.4 ppm. Effects of bacteria were uncoupled from DO by exposing eggs to bacterial cells suspended in NaCl solution. Over a 4-h exposure period, 93.8% of eggs hatched while DO concentration changed minimally from 7.62 to 7.50 ppm. Removal of bacteria by ultra-filtration and cell-free filtrate resulted in only 52.0% of eggs hatching after 4-h at an average DO concentration of 5.5 ppm. CONCLUSIONS/SIGNIFICANCE: Collectively, the results provide compelling evidence that bacteria or water-soluble compounds secreted by bacteria, not just low DO concentration, stimulate hatching of Ae. aegypti eggs. However, the specific cues involved remain to be identified. These research findings contribute new insight into an important aspect of the oviposition biology of Ae. aegypti, a virus vector of global importance, providing the basis for a new

The spatial ecology of free-ranging domestic pigs (Sus scrofa) in western Kenya.

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Thomas, Lian F; de Glanville, William A; Cook, Elizabeth A; Fèvre, Eric M

2013-03-07

In many parts of the developing world, pigs are kept under low-input systems where they roam freely to scavenge food. These systems allow poor farmers the opportunity to enter into livestock keeping without large capital investments. This, combined with a growing demand for pork, especially in urban areas, has led to an increase in the number of small-holder farmers keeping free range pigs as a commercial enterprise. Despite the benefits which pig production can bring to a household, keeping pigs under a free range system increases the risk of the pig acquiring diseases, either production-limiting or zoonotic in nature. This study used Global Positioning System (GPS) technology to track free range domestic pigs in rural western Kenya, in order to understand their movement patterns and interactions with elements of the peri-domestic environment. We found that these pigs travel an average of 4,340 m in a 12 hr period and had a mean home range of 10,343 m(2) (range 2,937-32,759 m(2)) within which the core utilisation distribution was found to be 964 m(2) (range 246-3,289 m(2)) with pigs spending on average 47% of their time outside their homestead of origin. These are the first data available on the home range of domestic pigs kept under a free range system: the data show that pigs in these systems spend much of their time scavenging outside their homesteads, suggesting that these pigs may be exposed to infectious agents over a wide area. Control policies for diseases such as Taenia solium, Trypanosomiasis, Trichinellosis, Toxoplasmosis or African Swine Fever therefore require a community-wide focus and pig farmers require education on the inherent risks of keeping pigs under a free range system. The work presented here will enable future research to incorporate movement data into studies of disease transmission, for example for the understanding of transmission of African Swine Fever between individuals, or in relation to the life-cycle of parasites including Taenia

Tick-, Flea-, and Louse-Borne Diseases of Public Health and Veterinary Significance in Nigeria

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Oluwaseun Oguntomole

2018-01-01

Full Text Available Mosquito-borne diseases are common high-impact diseases in tropical and subtropical areas. However, other non-mosquito vector-borne pathogens (VBPs may share their geographic distribution, seasonality, and clinical manifestations, thereby contributing their share to the morbidity and mortality caused by febrile illnesses in these regions. The purpose of this work was to collect and review existing information and identify knowledge gaps about tick, flea-, and louse-borne diseases of veterinary and public health significance in Nigeria. Full-length articles about VBPs were reviewed and relevant information about the vectors, their hosts, geographic distribution, seasonality, and association(s with human or veterinary diseases was extracted. Specific laboratory tools used for detection and identification of VBPs in Nigeria were also identified. A total of 62 original publications were examined. Substantial information about the prevalence and impacts of ticks and fleas on pet and service dogs (18 articles, and livestock animals (23 articles were available; however, information about their association with and potential for causing human illnesses was largely absent despite the zoonotic nature of many of these peri-domestic veterinary diseases. Recent publications that employed molecular methods of detection demonstrated the occurrence of several classic (Ehrlichia canis, Rickettsia africae, Bartonella sp. and emerging human pathogens (R. aeschlimannii, Neoehrlichia mikurensis in ticks and fleas. However, information about other pathogens often found in association with ticks (R. conorii and fleas (R. typhi, R. felis across the African continent was lacking. Records of louse-borne epidemic typhus in Nigeria date to 1947; however, its current status is not known. This review provides an essential baseline summary of the current knowledge in Nigeria of non-mosquito VBPs, and should stimulate improvements in the surveillance of the veterinary and

Assessment of contemporary genetic diversity and inter-taxa/inter-region exchange of avian paramyxovirus serotype 1 in wild birds sampled in North America

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Ramey, Andy M.; Goraichuk, Iryna V.; Hicks, Joseph T.; Dimitrov, Kiril M.; Poulson, Rebecca L.; Stallknecht, David E.; Bahl, Justin; Afonso, Claudio L.

2017-01-01

BackgroundAvian paramyxovirus serotype 1 (APMV-1) viruses are globally distributed, infect wild, peridomestic, and domestic birds, and sometimes lead to outbreaks of disease. Thus, the maintenance, evolution, and spread of APMV-1 viruses are relevant to avian health.MethodsIn this study we sequenced the fusion gene from 58 APMV-1 isolates recovered from thirteen species of wild birds sampled throughout the USA during 2007–2014. We analyzed sequence information with previously reported data in order to assess contemporary genetic diversity and inter-taxa/inter-region exchange of APMV-1 in wild birds sampled in North America.ResultsOur results suggest that wild birds maintain previously undescribed genetic diversity of APMV-1; however, such diversity is unlikely to be pathogenic to domestic poultry. Phylogenetic analyses revealed that APMV-1 diversity detected in wild birds of North America has been found in birds belonging to numerous taxonomic host orders and within hosts inhabiting multiple geographic regions suggesting some level of viral exchange. However, our results also provide statistical support for associations between phylogenetic tree topology and host taxonomic order/region of sample origin which supports restricted exchange among taxa and geographical regions of North America for some APMV-1 sub-genotypes.ConclusionsWe identify previously unrecognized genetic diversity of APMV-1 in wild birds in North America which is likely a function of continued viral evolution in reservoir hosts. We did not, however, find support for the emergence or maintenance of APMV-1 strains predicted to be pathogenic to poultry in wild birds of North America outside of the order Suliformes (i.e., cormorants). Furthermore, genetic evidence suggests that ecological drivers or other mechanisms may restrict viral exchange among taxa and regions of North America. Additional and more systematic sampling for APMV-1 in North America would likely provide further inference on viral

Factors affecting infestation by Triatoma infestans in a rural area of the humid Chaco in Argentina: a multi-model inference approach.

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Gurevitz, Juan M; Ceballos, Leonardo A; Gaspe, María Sol; Alvarado-Otegui, Julián A; Enríquez, Gustavo F; Kitron, Uriel; Gürtler, Ricardo E

2011-10-01

Transmission of Trypanosoma cruzi by Triatoma infestans remains a major public health problem in the Gran Chaco ecoregion, where understanding of the determinants of house infestation is limited. We conducted a cross-sectional study to model factors affecting bug presence and abundance at sites within house compounds in a well-defined rural area in the humid Argentine Chaco. Triatoma infestans bugs were found in 45.9% of 327 inhabited house compounds but only in 7.4% of the 2,584 sites inspected systematically on these compounds, even though the last insecticide spraying campaign was conducted 12 years before. Infested sites were significantly aggregated at distances of 0.8-2.5 km. The most frequently infested ecotopes were domiciles, kitchens, storerooms, chicken coops and nests; corrals were rarely infested. Domiciles with mud walls and roofs of thatch or corrugated tarred cardboard were more often infested (32.2%) than domiciles with brick-and-cement walls and corrugated metal-sheet roofs (15.1%). A multi-model inference approach using Akaike's information criterion was applied to assess the relative importance of each variable by running all possible (17,406) models resulting from all combinations of variables. Availability of refuges for bugs, construction with tarred cardboard, and host abundance (humans, dogs, cats, and poultry) per site were positively associated with infestation and abundance, whereas reported insecticide use showed a negative association. Ethnic background (Creole or Toba) adjusted for other factors showed little or no association. Promotion and effective implementation of housing improvement (including key peridomestic structures) combined with appropriate insecticide use and host management practices are needed to eliminate infestations. Fewer refuges are likely to result in fewer residual foci after insecticide spraying, and will facilitate community-based vector surveillance. A more integrated perspective that considers simultaneously

The influence of moonlight and lunar periodicity on the efficacy of CDC light trap in sampling Phlebotomus (Larroussius) orientalis Parrot, 1936 and other Phlebotomus sandflies (Diptera: Psychodidae) in Ethiopia.

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Gebresilassie, Araya; Yared, Solomon; Aklilu, Essayas; Kirstein, Oscar David; Moncaz, Aviad; Tekie, Habte; Balkew, Meshesha; Warburg, Alon; Hailu, Asrat; Gebre-Michael, Teshome

2015-02-15

Phlebotomus orientalis is the main sandfly vector of visceral leishmaniasis in the north and northwest of Ethiopia. CDC light traps and sticky traps are commonly used for monitoring sandfly populations. However, their trapping efficiency is greatly influenced by various environmental factors including moonlight and lunar periodicity. In view of that, the current study assessed the effect of moonlight and lunar periodicity on the performance of light traps in collecting P. orientalis. Trapping of P. orientalis and other Phlebotomus spp. was conducted for 7 months between December 2012 and June 2013 using CDC light traps and sticky traps from peri-domestic and agricultural fields. Throughout the trapping periods, collections of sandfly specimens were carried out for 4 nights per month, totaling 28 trapping nights that coincided with the four lunar phases (viz., first quarter, third quarter, new and full moon) distributed in each month. In total, 13,533 sandflies of eight Phlebotomus species (P. orientalis, P. bergeroti, P. rodhaini, P. duboscqi, P. papatasi, P. martini, P. lesleyae and P. heischi) were recorded. The predominant species was P. orientalis in both trapping sites and by both methods of collection in all lunar phases. A significant difference (P lunar phases. The highest mean number (231.13 ± 36.27 flies/trap/night) of P. orientalis was collected during the new moon phases, when the moonlight is absent. Fewer sandflies were attracted to light traps during a full moon. However, the number of P. orientalis and the other Phlebotomus spp. from sticky traps did not differ in their density among the four lunar phases (P = 0.122). Results of the current study demonstrated that the attraction and trapping efficiency of CDC light traps is largely influenced by the presence moonlight, especially during a full moon. Therefore, sampling of sandflies using light traps to estimate population density and other epidemiological studies in the field should take

Factors Affecting Infestation by Triatoma infestans in a Rural Area of the Humid Chaco in Argentina: A Multi-Model Inference Approach

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Gurevitz, Juan M.; Ceballos, Leonardo A.; Gaspe, María Sol; Alvarado-Otegui, Julián A.; Enríquez, Gustavo F.; Kitron, Uriel; Gürtler, Ricardo E.

2011-01-01

Background Transmission of Trypanosoma cruzi by Triatoma infestans remains a major public health problem in the Gran Chaco ecoregion, where understanding of the determinants of house infestation is limited. We conducted a cross-sectional study to model factors affecting bug presence and abundance at sites within house compounds in a well-defined rural area in the humid Argentine Chaco. Methodology/Principal Findings Triatoma infestans bugs were found in 45.9% of 327 inhabited house compounds but only in 7.4% of the 2,584 sites inspected systematically on these compounds, even though the last insecticide spraying campaign was conducted 12 years before. Infested sites were significantly aggregated at distances of 0.8–2.5 km. The most frequently infested ecotopes were domiciles, kitchens, storerooms, chicken coops and nests; corrals were rarely infested. Domiciles with mud walls and roofs of thatch or corrugated tarred cardboard were more often infested (32.2%) than domiciles with brick-and-cement walls and corrugated metal-sheet roofs (15.1%). A multi-model inference approach using Akaike's information criterion was applied to assess the relative importance of each variable by running all possible (17,406) models resulting from all combinations of variables. Availability of refuges for bugs, construction with tarred cardboard, and host abundance (humans, dogs, cats, and poultry) per site were positively associated with infestation and abundance, whereas reported insecticide use showed a negative association. Ethnic background (Creole or Toba) adjusted for other factors showed little or no association. Conclusions/Significance Promotion and effective implementation of housing improvement (including key peridomestic structures) combined with appropriate insecticide use and host management practices are needed to eliminate infestations. Fewer refuges are likely to result in fewer residual foci after insecticide spraying, and will facilitate community-based vector

Factors that are associated with the risk of acquiring Plasmodium knowlesi malaria in Sabah, Malaysia: a case-control study protocol.

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Grigg, M J; William, T; Drakeley, C J; Jelip, J; von Seidlein, L; Barber, B E; Fornace, K M; Anstey, N M; Yeo, T W; Cox, J

2014-08-22

Plasmodium knowlesi has long been present in Malaysia, and is now an emerging cause of zoonotic human malaria. Cases have been confirmed throughout South-East Asia where the ranges of its natural macaque hosts and Anopheles leucosphyrus group vectors overlap. The majority of cases are from Eastern Malaysia, with increasing total public health notifications despite a concurrent reduction in Plasmodium falciparum and P. vivax malaria. The public health implications are concerning given P. knowlesi has the highest risk of severe and fatal disease of all Plasmodium spp in Malaysia. Current patterns of risk and disease vary based on vector type and competence, with individual exposure risks related to forest and forest-edge activities still poorly defined. Clustering of cases has not yet been systematically evaluated despite reports of peri-domestic transmission and known vector competence for human-to-human transmission. A population-based case-control study will be conducted over a 2-year period at two adjacent districts in north-west Sabah, Malaysia. Confirmed malaria cases presenting to the district hospital sites meeting relevant inclusion criteria will be requested to enrol. Three community controls matched to the same village as the case will be selected randomly. Study procedures will include blood sampling and administration of household and individual questionnaires to evaluate potential exposure risks associated with acquisition of P. knowlesi malaria. Secondary outcomes will include differences in exposure variables between P. knowlesi and other Plasmodium spp, risk of severe P. knowlesi malaria, and evaluation of P. knowlesi case clustering. Primary analysis will be per protocol, with adjusted ORs for exposure risks between cases and controls calculated using conditional multiple logistic regression models. This study has been approved by the human research ethics committees of Malaysia, the Menzies School of Health Research, Australia, and the London

[The control of vectorial transmission].

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Silveira, Antônio Carlos; Dias, João Carlos Pinto

2011-01-01

Between 1950 and 1951, the first Prophylactic campaign against Chagas Diseases was carried on in Brazil by the so existing Serviço Nacional de Malária. The actions involving chemical vector control comprehended 74 municipalities along the Rio Grande Valley, between the States of São Paulo and Minas Gerais. Ever since, until 1975, the activities were performed according the availability of resources, being executed with more or less regularity and coverage. At that time, Chagas disease did no represent priority, in comparison with other endemic diseases prevalent in the Country. Even so, taking into account the accumulated data along those 25 years, the volume of work realized cannot be considered despicable. Nevertheless, it was few consistent, in terms of its impact on disease transmission. In 1975, with an additional injection of resources surpassed from the malaria program, plus the methodological systematization of the activities, and with the results of two extensive national inquiries (entomologic and serologic), the activities for vector control could be performed regularly, following two basic principles: interventions in always contiguous areas, progressively enlarged, and sustainability (continuity) of the activities, until being attained determined requirements and purpose previously established. Such actions and strategies lead into the exhaustion of the populations of the principal vector species, Triatoma infestans, no autochthonous and exclusively domiciliary, as well as the control of the domiciliary colonization of autochthonous species important to disease transmission. Vector transmission today is being considered residual, by means of some few native and peridomestic species, such as Triatoma brasiliensis and Triatoma pseudomaculata. There is, also, the risk of progressive domiciliation of some species before considered sylvatic, such as Panstrongylus lutzi and Triatoma rubrovaria. Finally, there is the possibility of the occurrence of cases

Are the London Declaration's 2020 goals sufficient to control Chagas disease?: Modeling scenarios for the Yucatan Peninsula.

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Lee, Bruce Y; Bartsch, Sarah M; Skrip, Laura; Hertenstein, Daniel L; Avelis, Cameron M; Ndeffo-Mbah, Martial; Tilchin, Carla; Dumonteil, Eric O; Galvani, Alison

2018-03-01

The 2020 Sustainable Development goals call for 100% certified interruption or control of the three main forms of Chagas disease transmission in Latin America. However, how much will achieving these goals to varying degrees control Chagas disease; what is the potential impact of missing these goals and if they are achieved, what may be left? We developed a compartmental simulation model that represents the triatomine, human host, and non-human host populations and vector-borne, congenital, and transfusional T. cruzi transmission between them in the domestic and peridomestic settings to evaluate the impact of limiting transmission in a 2,000 person virtual village in Yucatan, Mexico. Interruption of domestic vectorial transmission had the largest impact on T. cruzi transmission and prevalence in all populations. Most of the gains were achieved within the first few years. Controlling vectorial transmission resulted in a 46.1-83.0% relative reduction in the number of new acute Chagas cases for a 50-100% interruption in domestic vector-host contact. Only controlling congenital transmission led to a 2.4-8.1% (30-100% interruption) relative reduction in the total number of new acute cases and reducing only transfusional transmission led to a 0.1-0.3% (30-100% reduction). Stopping all three forms of transmission resulted in 0.5 total transmission events over five years (compared to 5.0 with no interruption); interrupting all forms by 30% resulted in 3.4 events over five years per 2,000 persons. While reducing domestic vectorial, congenital, and transfusional transmission can successfully reduce transmission to humans (up to 82% in one year), achieving the 2020 goals would still result in 0.5 new acute cases per 2,000 over five years. Even if the goals are missed, major gains can be achieved within the first few years. Interrupting transmission should be combined with other efforts such as a vaccine or improved access to care, especially for the population of already

Are the London Declaration’s 2020 goals sufficient to control Chagas disease?: Modeling scenarios for the Yucatan Peninsula

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Bartsch, Sarah M.; Skrip, Laura; Hertenstein, Daniel L.; Ndeffo-Mbah, Martial; Dumonteil, Eric O.; Galvani, Alison

2018-01-01

Background The 2020 Sustainable Development goals call for 100% certified interruption or control of the three main forms of Chagas disease transmission in Latin America. However, how much will achieving these goals to varying degrees control Chagas disease; what is the potential impact of missing these goals and if they are achieved, what may be left? Methods We developed a compartmental simulation model that represents the triatomine, human host, and non-human host populations and vector-borne, congenital, and transfusional T. cruzi transmission between them in the domestic and peridomestic settings to evaluate the impact of limiting transmission in a 2,000 person virtual village in Yucatan, Mexico. Results Interruption of domestic vectorial transmission had the largest impact on T. cruzi transmission and prevalence in all populations. Most of the gains were achieved within the first few years. Controlling vectorial transmission resulted in a 46.1–83.0% relative reduction in the number of new acute Chagas cases for a 50–100% interruption in domestic vector-host contact. Only controlling congenital transmission led to a 2.4–8.1% (30–100% interruption) relative reduction in the total number of new acute cases and reducing only transfusional transmission led to a 0.1–0.3% (30–100% reduction). Stopping all three forms of transmission resulted in 0.5 total transmission events over five years (compared to 5.0 with no interruption); interrupting all forms by 30% resulted in 3.4 events over five years per 2,000 persons. Conclusions While reducing domestic vectorial, congenital, and transfusional transmission can successfully reduce transmission to humans (up to 82% in one year), achieving the 2020 goals would still result in 0.5 new acute cases per 2,000 over five years. Even if the goals are missed, major gains can be achieved within the first few years. Interrupting transmission should be combined with other efforts such as a vaccine or improved access to

Babesia microti, human babesiosis, and Borrelia burgdorferi in Connecticut.

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Anderson, J F; Mintz, E D; Gadbaw, J J; Magnarelli, L A

1991-12-01

Babesia microti was isolated from a white-footed mouse (Peromyscus leucopus) that was captured in southeastern Connecticut in 1988, when the first human case of babesiosis acquired in Connecticut was recognized. To date, 13 cases of babesiosis have been reported in Connecticut, the largest number of human cases reported on the mainland United States. Two of nine patients quiried remembered a prior tick bite. Since Babesia parasites are known to be vectored only by ticks, we surmise that 12 of these infections were acquired via tick bites; 1 was obtained by blood transfusion (the patient was 46 years of age) from an endemically infected donor. The ages of the patients with tick-acquired babesiosis ranged from 61 to 95 years. Two patients died with active infections, and one patient died from chronic obstructive pulmonary disease soon after treatment with clindamycin and quinine. Indirect fluorescent-antibody titers of blood samples drawn at the time of hospitalization for 11 patients and at the time of active infection for 1 asymptomatic person ranged from 1:1,024 to 1:4,096. Five of eight patients with babesiosis also had significant immunoglobulin G or immunoglobulin M titers (1:640 to 1:5,120) to Borrelia burgdorferi. B. microti was isolated in Syrian hamsters inoculated with blood from 7 of 12 patients tested and was also isolated from mice captured in six towns. The peridomestic nature of the disease was demonstrated by isolating the parasite from white-footed mice captured in or near the yards of eight different patients. Of 59 mice tested, 27 were positive and 25 were coinfected with B. burgdorferi. The isolation of B. microti from a white-footed mouse captured in north-central Connecticut (West Hartford), away from the focus of human infections in southeastern Connecticut, suggests that this pathogen may spread into other areas where Ixodes dammini, the tick vector, becomes established.

Chagas disease in an area of recent occupation in Cochabamba, Bolivia Doença de Chagas numa área de ocupação recente em Cochabamba, Bolívia

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Hugo Albarracin-Veizaga

1999-06-01

Full Text Available INTRODUCTION: A descriptive, entomological and seroepidemiological study on Chagas disease was conducted in a place of recent occupation on the outskirts of Cochabamba, Bolivia: Avaroa/Primer de Mayo (population:3,000, where the socio-economic level is low and no control measures have been made available. METHODS: The immunofluorescent antibody test (IFAT was used for IgG and IgM anti-Trypanosoma cruzi antibodies in filter paper bloodspot eluates from 128 subjects (73 females, 55 males selected by systematic sampling. Concerning each subject age, gender, birthplace, occupation, duration of residence and building materials used in their houses were recorded. Vectors were captured both in domestic and peridomestic environments. RESULTS: Seropositive, 12.5% (16/128: females, 15.1% (11/73; males, 9.1% (5/55. Average time of residence: 6.1 years for the whole population sample and 7.4 years for the seropositive subjects. Most houses had adobe walls (76.7% , n= 30, galvanized iron rooves (86.7% and earthen floors (53.4% 80% of the walls had crevices. One hundred forty seven specimens of Triatoma infestans were captured, of which 104 (70.7% were domestic, and 1 peridomestic Triatoma sordida. Precipitin host identification: birds, 67.5%; humans, 27.8%; rodents, 11.9%; dogs, 8.7%; cats, 1.6%. House infestation and density indices were 53.3 and 493.0 respectively. We found 21 (14.3% specimens of T. infestans infected with trypanosomes, 18 (85.7% of which in domestic environments. DISCUSSION: The elements for the vector transmission of Chagas disease are present in Avaroa/Primer de Mayo and the ancient custom of keeping guinea pigs indoors adds to the risk of human infection. In neighboring Cochabamba, due to substandard quality control, contaminated blood transfusions are not infrequent, which further aggravates the spread of Chagas disease. Prompt action to check the transmission of this infection, involving additionally the congenital and transfusional

Gas production, microbial synthesis by radio phosphorus and digestibility of babassu and mofumbo in sheep diets; Producao de gases, sintese microbiana pelo radiofosforo e digestibilidade do babacu e mofumbo em dietas de ovinos

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Abdalla Filho, Adibe Luiz

2015-06-01

When food shortages in natural pastures is committed to animal nutrition, small ruminants can incorporate into their diets the leaves of other plants, such as trees and shrubs, many of them rich in secondary metabolites such as tannins and which still lack of studies about its effect on animal productivity. In order to verify the possibility of using leaves of Orbignya phalerata (Babassu) and Combretum leprosum (Mofumbo) in feed and to evaluate the effect of their inclusion in the sheep production system, two studies were conducted at the Animal Nutrition Laboratory of Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Piracicaba (LANA/CENA-USP). The first study evaluated the performance variables, biochemical and hematological parameters and also determined the microbial protein synthesis, nutrient apparent digestibility and enteric production of methane (CH4). The second study assessed the carcass characteristics, fatty acid profile and meat color of male sheep used in the first study. The experimental treatments were diets with forages to concentrate rate of 50:50, drawn up on the basis of using the leaves of the experimental plants replacing 30% of the Cynodon dactylon (Tifton-85) hay, resulting in three treatments: Control (no hay replacement), Babassu and Mofumbo. In the first study, there were used 24 Santa Ines sheep, in a randomized experimental design with eight repetitions for each treatment and 48 days of trial period. Also during this period, an in vitro microbial protein synthesis was performed using the radio phosphorus using five different inoculum of each studied treatment. After this period, for nine days, six animals from each treatment were allocated in metabolic cages for determining the nutrient apparent digestibility, microbial protein synthesis and nitrogen balance. Simultaneously it was quantified the enteric CH4 production in vivo. The Control group showed greater (P < 0.05) apparent digestibility of acid detergent fiber

Gas production, microbial synthesis by radio phosphorus and digestibility of babassu and mofumbo in sheep diets

International Nuclear Information System (INIS)

Abdalla Filho, Adibe Luiz

2015-01-01

When food shortages in natural pastures is committed to animal nutrition, small ruminants can incorporate into their diets the leaves of other plants, such as trees and shrubs, many of them rich in secondary metabolites such as tannins and which still lack of studies about its effect on animal productivity. In order to verify the possibility of using leaves of Orbignya phalerata (Babassu) and Combretum leprosum (Mofumbo) in feed and to evaluate the effect of their inclusion in the sheep production system, two studies were conducted at the Animal Nutrition Laboratory of Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Piracicaba (LANA/CENA-USP). The first study evaluated the performance variables, biochemical and hematological parameters and also determined the microbial protein synthesis, nutrient apparent digestibility and enteric production of methane (CH4). The second study assessed the carcass characteristics, fatty acid profile and meat color of male sheep used in the first study. The experimental treatments were diets with forages to concentrate rate of 50:50, drawn up on the basis of using the leaves of the experimental plants replacing 30% of the Cynodon dactylon (Tifton-85) hay, resulting in three treatments: Control (no hay replacement), Babassu and Mofumbo. In the first study, there were used 24 Santa Ines sheep, in a randomized experimental design with eight repetitions for each treatment and 48 days of trial period. Also during this period, an in vitro microbial protein synthesis was performed using the radio phosphorus using five different inoculum of each studied treatment. After this period, for nine days, six animals from each treatment were allocated in metabolic cages for determining the nutrient apparent digestibility, microbial protein synthesis and nitrogen balance. Simultaneously it was quantified the enteric CH4 production in vivo. The Control group showed greater (P < 0.05) apparent digestibility of acid detergent fiber

Perfil alimentario de Triatoma rubrovaria (Blanchard, 1843 (Hemiptera, Triatominae en ámbitos peridomiciliarios, de una localidad rural de Uruguay Feeding patterns of Triatoma rubrovaria (Blanchard, 1843 (Hemiptera, Triatominae in peridomestic habitats, in a rural area of Uruguay

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Roberto Salvatella

1994-08-01

Full Text Available En una localidad con población rural dispersa ("La Bolsa", 3ª seccional, dpto. de Artigas, Uruguay se estudió, en ámbitos peridomiciliarios, el perfil alimentario de T. rubrovaria (triatomíneo silvestre y potencial vector secundario de colonización intradomiciliaria, utilizándose la técnica de doble difusión en agar, enfrentando contenido promesentérico frente a un panel de 13 sueros. Se pudo detectar en 120 insectos 251 identificaciones de fuente hematofágica con alimentación predominante en mamíferos (73%, pero marcado eclectismo alimentario (mamíferos, aves, reptiles y cucarachas, incluyendo hematofagia sobre seres humanos en un 8% de las identificaciones totales. La micropredación de hemolinfa lo ubicaría en una situación evolutiva primitiva, intermedia entre predator/entomófago y triatomineo/hematófago, que comparte con T. circunmaculata. Los mamíferos detectados con mayor frecuencia fueron dasipódidos y bóvidos, aunque la fuente hematofágica, salvo en los adultos alados, se constituye en un fenómeno de proximidad ocasional por cohabitación de un mismo habitat. La frecuencia de alimentación sobre hombre, hallada en un ambiente peridomiciliario, aporta un importante elemento a su capacidad vectorial potencial. En el análisis espacial de las dietas se muestra al peridomicilio como un área de interacción de hospederos domésticos, silvestres y sinantrópicos. La infección tripanosómica fue mínima comparada con las altas tasas de infección de ámbitos silvestres.It has been studied the feeding patterns of Triatoma rubrovaria (wild triatominae bug, and intradomiciliary secondary vector of T. cruzi in a rural area of "La Bolsa" (Department of Artigas. Agar double diffusion test were used for analyze the blood meal, from 120 insects, which were confronted to 13 antisera. It has 251 identify blood meals, and the most frequently was mamalian host (73%, but it has a variable source of feeding (mammals, birds, reptils and cockroach, including humans rate 8% of the total. The identify of haemolimphe as feed, place this triatominae bug as an intermediary vector between predator and haematophagous. The most usual mammals are dasypodides and bovines. The frecuence of human blood meal near the dwellings, shows its potentiality as vectors. Therefore, the peridomicile is an area of interaction between, domestic, wild and sinantropic host. The trypanosomic infection's rate at peridomiciles was lesser those at wild areas.

Spatial and temporal distribution of house infestation by Triatoma infestans in the Toro Toro municipality, Potosi, Bolivia.

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Espinoza Echeverria, Jorge; Rodriguez, Antonio Nogales; Cortez, Mirko Rojas; Diotaiuti, Liléia Gonçalves; Gorla, David E

2017-02-02

Triatoma infestans is the main vector of Trypanosoma cruzi in Bolivia. The species is present both in domestic and peridomestic structures of rural areas, and in wild ecotopes of the Andean valleys and the Great Chaco. The identification of areas persistently showing low and high house infestation by the vector is important for the management of vector control programs. This study aimed at analyzing the temporal and spatial distribution of house infestation by T. infestans in the Toro Toro municipality (Potosi, Bolivia) between 2009 and 2014, and its association with environmental variables. House infestation and T. infestans density were calculated from entomological surveys of houses in the study area, using a fixed-time effort sampling technique. The spatial heterogeneity of house infestation was evaluated using the SatScan statistic. Association between house infestation with Bioclim variables (Worldclim database) and altitude was analyzed using a generalized linear model (GLM) with a logit link. Model selection was based on the Akaike information criteria after eliminating collinearity between variables using the variable inflation factor. The final model was used to create a probability map of house infestation for the Toro Toro municipality. A total of 73 communities and 16,489 house evaluation events were analyzed. Presence of T. infestans was recorded on 480 house evaluation events, giving an overall annual infestation of 2.9% during the studied period (range 1.5-5.4% in 2009 and 2012). Vector density remained at about 1.25 insects/ house. Infestation was highly aggregated in five clusters, including 11 communities. Relative risk of infestation within these clusters was 1.7-3.9 times the value for the regional average. Four environmental variables were identified as good descriptors of house infestation, explaining 57% of house infestation variability. The model allowed the estimation of a house infestation surface for the Toro Toro municipality. This

Host-feeding patterns of Aedes albopictus (Diptera: Culicidae) in relation to availability of human and domestic animals in suburban landscapes of central North Carolina.

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Richards, Stephanie L; Ponnusamy, Loganathan; Unnasch, Thomas R; Hassan, Hassan K; Apperson, Charles S

2006-05-01

Aedes albopictus (Skuse) (Diptera: Culicidae) is a major nuisance mosquito and a potential arbovirus vector. The host-feeding patterns of Ae. albopictus were investigated during the 2002 and 2003 mosquito seasons in suburban neighborhoods in Wake County, Raleigh, NC. Hosts of blood-fed Ae. albopictus (n = 1,094) were identified with an indirect enzyme-linked immunosorbent assay, by using antisera made in New Zealand White rabbits to the sera of animals that would commonly occur in peridomestic habitats. Ae. albopictus fed predominantly on mammalian hosts (83%). Common mammalian hosts included humans (24%), cats (21%), and dogs (14%). However, a notable proportion (7%) of bloodmeals also was taken from avian hosts. Some bloodmeals taken from birds were identified to species by a polymerase chain reaction-heteroduplex assay (PCR-HDA). Ae. albopictus fed predominantly on chickens and a northern cardinal. PCR-HDA failed to produce detectable products for 29 (58%) of 50 bloodmeals for which DNA had been amplified, indicating that these mosquitoes took mixed bloodmeals from avian and nonavian hosts. Ae. albopictus preference for humans, dogs, and cats was determined by calculating host-feeding indices for the three host pairs based on the proportion of host specific blood-fed mosquitoes collected in relation to the number of specific hosts per residence as established by a door-to-door survey conducted in 2003. Estimates of the average amount of time that residents and their pets (cats and dogs) spent out of doors were obtained. Host-feeding indices based only on host abundance indicated that Ae. albopictus was more likely to feed on domestic animals. However, when feeding indices were time-weighted, Ae. albopictus fed preferentially upon humans. Ae. albopictus blood feeding on humans was investigated using a STR/PCR-DNA profiling technique that involved amplification of three short tandem repeats loci. Of 40 human bloodmeals, 32 (80%) were from a single human, whereas

Isolation of Salmonella enterica and serologic reactivity to Leptospira interrogans in opossums (Didelphis virginiana from Yucatán, México Aislamiento de Salmonella enterica y reactividad serológica a Leptospira interrogans en tlacuaches (Didelphis virginiana de Yucatán, México

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Hugo Antonio RUIZ-PIÑA

2002-07-01

Full Text Available The presence of Salmonella enterica and serologic evidence of infection by Leptospira interrogans, were detected in the opossum Didelphis virginiana in a semi-urban locality of the Yucatán State, México. Ninety-one opossums were captured during the period April 1996 and May 1998. From a total of 17 feces samples, four Salmonella enterica subsp. enterica serotypes (Sandiego, Newport, Anatum, and Minnesota, and one Salmonella enterica subsp. arizonae serovar O44:Z4,Z23:- were isolated. Some opossums presented mixed infections. From 81 sera samples, four (4.9% were positive to antibodies to Leptospira serovars pomona and wolfii. Both animals infected with Salmonella enterica and those serologically positive to Leptospira interrogans were captured in peridomestic habitat. Opossums infected with Salmonella enterica, were captured in dry season, and those seropositive to Leptospira interrogans during the rainy season. The implications of infection and reactivity of these zoonotic pathogens in D. virginiana in the Yucatan state are briefly discussed.La presencia de Salmonella enterica y evidencia serológica de infección por Leptospira interrogans fueron detectadas en tlacuaches de la especie Didelphis virginiana capturados en una localidad semi-urbana del estado de Yucatán, México. Se capturaron 91 marsupiales durante el período de abril de 1996 a mayo de 1998. De un total de 17 muestras de heces, se aislaron cuatro serotipos de Salmonella enterica subsp. enterica (Sandiego, Newport, Anatum y Minnesota y una Salmonella enterica subsp. arizonae serovar O44:Z4,Z23:-. En algunos tlacuaches se registraron infecciones mixtas. De 81 muestras de suero, cuatro (4,9% presentaron reacciones positivas con los serovares pomona y wolffi, ambos pertenecientes al género Leptospira. Los tlacuaches con serología positiva fueron capturados en el hábitat peridomiciliar. Los animales infectados con Salmonella enterica fueron capturados en los períodos de seca y

Individual-level factors associated with the risk of acquiring human Plasmodium knowlesi malaria in Malaysia: a case-control study.

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Grigg, Matthew J; Cox, Jonathan; William, Timothy; Jelip, Jenarun; Fornace, Kimberly M; Brock, Patrick M; von Seidlein, Lorenz; Barber, Bridget E; Anstey, Nicholas M; Yeo, Tsin W; Drakeley, Christopher J

2017-06-09

The emergence of human malaria due to the monkey parasite Plasmodium knowlesi threatens elimination efforts in southeast Asia. Changes in land use are thought to be driving the rise in reported P knowlesi cases, but the role of individual-level factors is unclear. To address this knowledge gap we assessed human and environmental factors associated with zoonotic knowlesi malaria risk. We did this population-based case-control study over a 2 year period in the state of Sabah in Malaysia. We enrolled cases with microscopy-positive, PCR-confirmed malaria who presented to two primary referral hospitals serving the adjacent districts of Kudat and Kota Marudu. We randomly selected three malaria-negative community controls per case, who were matched by village within 2 weeks of case detection. We obtained questionnaire data on demographics, behaviour, and residential malaria risk factors, and we also assessed glucose-6-phosphate dehydrogenase (G6PD) enzyme activity. We used conditional logistic regression models to evaluate exposure risk between P knowlesi cases and controls, and between P knowlesi and human-only Plasmodium spp malaria cases. From Dec 5, 2012, to Jan 30, 2015, we screened 414 patients and subsequently enrolled 229 cases with P knowlesi malaria mono-infection and 91 cases with other Plasmodium spp infection. We enrolled 953 matched controls, including 683 matched to P knowlesi cases and 270 matched to non- P knowlesi cases. Age 15 years or older (adjusted odds ratio [aOR] 4·16, 95% CI 2·09-8·29, pwork (3·50, CI, 1·34-9·15, p=0·011), sleeping outside (3·61, 1·48-8·85, p=0·0049), travel (2·48, 1·45-4·23, p=0·0010), being aware of the presence of monkeys in the past 4 weeks (3·35, 1·91-5·88, pworking in agricultural areas were at highest risk of knowlesi malaria, although peri-domestic transmission also occurrs. Human behavioural factors associated with P knowlesi transmission could be targeted in future public health interventions. United

Serological and PCR investigation of Yersinia pestis in potential reservoir hosts from a plague outbreak focus in Zambia.

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Nyirenda, S S; Hang'ombe, B M; Mulenga, E; Kilonzo, B S

2017-07-28

Plague is a bacterial zoonotic disease, caused by Yersinia pestis. Rodents are the natural hosts with fleas as the vehicle of disease transmission. Domestic and wild dogs and cats have also been identified as possible disease hosts. In Zambia, plague outbreaks have been reported in the Southern and Eastern regions in the last 20 years. Based on these observations, Y. pestis could possibly be endemically present in the area. To substantiate such possibility, sera samples were collected from rodents, shrews, dogs and cats for detection of antibodies against Fraction 1 gene (Fra1) of Y. pestis while organs from rodents and shrews, and fleas from both dogs and rodents were collected to investigate plasminogen activator gene (pla gene) of Y. pestis using ELISA and PCR respectively. A total of 369 blood samples were collected from domestic carnivores, shrews and domestic and peri-domestic rodents while 199 organs were collected from the rodents and shrews. Blood samples were tested for antibodies against Fra1 antigen using ELISA and 3% (5/165) (95% CI 0.99-6.93%) dogs were positive while all cats were negative. Of 199 sera from rodents and shrews, 12.6% (95% CI 8.30-17.98%) were positive for antibodies against Fra1 using anti-rat IgG secondary antibody while using anti-mouse IgG secondary antibody, 17.6% (95% CI 12.57-23.60%) were positive. PCR was run on the organs and 2.5% (95% CI 0.82-5.77%) were positive for plasminogen activator gene of Y. pestis and the amplicons were sequenced and showed 99% identity with Y. pestis reference sequences. All 82 fleas collected from animals subjected to PCR, were negative for pla gene. The specific rat-flea and dog-flea indices were 0.19 and 0.27 respectively, which were lower than the level required to enhance chances of the disease outbreak. We concluded that plague was still endemic in the area and the disease may infect human beings if contact is enhanced between reservoir hosts and flea vectors. The lower specific rodent

Mayaro virus infection in amazonia: a multimodel inference approach to risk factor assessment.

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Fernando Abad-Franch

Full Text Available BACKGROUND: Arboviral diseases are major global public health threats. Yet, our understanding of infection risk factors is, with a few exceptions, considerably limited. A crucial shortcoming is the widespread use of analytical methods generally not suited for observational data--particularly null hypothesis-testing (NHT and step-wise regression (SWR. Using Mayaro virus (MAYV as a case study, here we compare information theory-based multimodel inference (MMI with conventional analyses for arboviral infection risk factor assessment. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional survey of anti-MAYV antibodies revealed 44% prevalence (n = 270 subjects in a central Amazon rural settlement. NHT suggested that residents of village-like household clusters and those using closed toilet/latrines were at higher risk, while living in non-village-like areas, using bednets, and owning fowl, pigs or dogs were protective. The "minimum adequate" SWR model retained only residence area and bednet use. Using MMI, we identified relevant covariates, quantified their relative importance, and estimated effect-sizes (β ± SE on which to base inference. Residence area (β(Village  =  2.93 ± 0.41; β(Upland = -0.56 ± 0.33, β(Riverbanks  =  -2.37 ± 0.55 and bednet use (β = -0.95 ± 0.28 were the most important factors, followed by crop-plot ownership (β  =  0.39 ± 0.22 and regular use of a closed toilet/latrine (β = 0.19 ± 0.13; domestic animals had insignificant protective effects and were relatively unimportant. The SWR model ranked fifth among the 128 models in the final MMI set. CONCLUSIONS/SIGNIFICANCE: Our analyses illustrate how MMI can enhance inference on infection risk factors when compared with NHT or SWR. MMI indicates that forest crop-plot workers are likely exposed to typical MAYV cycles maintained by diurnal, forest dwelling vectors; however, MAYV might also be circulating in nocturnal, domestic-peridomestic cycles

Ecological factors related to the widespread distribution of sylvatic Rhodnius ecuadoriensis populations in southern Ecuador

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Grijalva Mario J

2012-01-01

Full Text Available Abstract Background Chagas disease transmission risk is a function of the presence of triatomines in domestic habitats. Rhodnius ecuadoriensis is one of the main vectors implicated in transmission of Trypanosoma cruzi in Ecuador. This triatomine species is present in domestic, peridomestic and sylvatic habitats in the country. To determine the distribution of sylvatic populations of R. ecuadoriensis and the factors related to this distribution, triatomine searches were conducted between 2005 and 2009 in southern Ecuador. Methods Manual triatomine searches were conducted by skilled bug collectors in 23 communities. Sylvatic searched sites were selected by a directed sampling, where microhabitats were selected by the searchers and b random sampling, where sampling points where randomly generated. Domiciliary triatomine searches were conducted using the one man-hour method. Natural trypanosome infection was determined by microscopic examination and PCR. Generalized linear models were used to test the effect of environmental factors on the presence of sylvatic triatomines. Results In total, 1,923 sylvatic individuals were collected representing a sampling effort of 751 man-hours. Collected sylvatic triatomines were associated with mammal and bird nests. The 1,219 sampled nests presented an infestation index of 11.9%, a crowding of 13 bugs per infested nest, and a colonization of 80% of the nests. Triatomine abundance was significantly higher in squirrel (Sciurus stramineus nests located above five meters from ground level and close to the houses. In addition, 8.5% of the 820 examined houses in the same localities were infested with triatomines. There was a significant correlation between R. ecuadoriensis infestation rates found in sylvatic and synanthropic environments within communities (p = 0.012. Parasitological analysis revealed that 64.7% and 15.7% of the sylvatic bugs examined (n = 300 were infected with Trypanosoma cruzi and T. rangeli

Ecological factors related to the widespread distribution of sylvatic Rhodnius ecuadoriensis populations in southern Ecuador

Science.gov (United States)

2012-01-01

Background Chagas disease transmission risk is a function of the presence of triatomines in domestic habitats. Rhodnius ecuadoriensis is one of the main vectors implicated in transmission of Trypanosoma cruzi in Ecuador. This triatomine species is present in domestic, peridomestic and sylvatic habitats in the country. To determine the distribution of sylvatic populations of R. ecuadoriensis and the factors related to this distribution, triatomine searches were conducted between 2005 and 2009 in southern Ecuador. Methods Manual triatomine searches were conducted by skilled bug collectors in 23 communities. Sylvatic searched sites were selected by a) directed sampling, where microhabitats were selected by the searchers and b) random sampling, where sampling points where randomly generated. Domiciliary triatomine searches were conducted using the one man-hour method. Natural trypanosome infection was determined by microscopic examination and PCR. Generalized linear models were used to test the effect of environmental factors on the presence of sylvatic triatomines. Results In total, 1,923 sylvatic individuals were collected representing a sampling effort of 751 man-hours. Collected sylvatic triatomines were associated with mammal and bird nests. The 1,219 sampled nests presented an infestation index of 11.9%, a crowding of 13 bugs per infested nest, and a colonization of 80% of the nests. Triatomine abundance was significantly higher in squirrel (Sciurus stramineus) nests located above five meters from ground level and close to the houses. In addition, 8.5% of the 820 examined houses in the same localities were infested with triatomines. There was a significant correlation between R. ecuadoriensis infestation rates found in sylvatic and synanthropic environments within communities (p = 0.012). Parasitological analysis revealed that 64.7% and 15.7% of the sylvatic bugs examined (n = 300) were infected with Trypanosoma cruzi and T. rangeli respectively, and 8% of the

Study of a cutaneous leishmaniasis outbreak in General Vedia, Province of Chaco, 1996 Surto de leishmaniose cutânea em General Vedia, Provincia de Chaco, 1996

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O. Daniel SALOMON

2001-04-01

Full Text Available Between March and July 1996, a focalized epidemic outbreak of cutaneous leishmaniasis in General Vedia, province of Chaco, associated to the gallery forest of the Oro river was verified. The incidence rate in the area, which was 0-2/000 cases in preceding years, reached 8/000 cases in 1996. The risk of symptomatic infection was similar between sexes, but was different when analizing the different age groups by sex, suggesting a greater relative importance of the peridomestic transmission for the females and of the transmission in the subtropical forest for the males. Specimens of Lutzomyia intermedia, a species already incriminated as a vector of Leishmaniasis in other provinces of northern Argentina, were captured and identified in the focus locality in May 1996. The possible causes of the outbreak related to the climatic variables and the vector abundance are analyzed and the results in the framework of possible preventive and control activities are discussed.Entre março e julho de 1996, foi verificado um surto epidêmico focalizado de leishmaniose cutânea na localidade de Geral Vedia, província de Chaco, associado com a floresta de galeria do rio de Oro. A taxa de incidência na área que era 0-2/000 casos em anos anteriores, alcançou 8/000 casos em 1996. O risco de infecção sintomática era semelhante entre sexos, mas era diferente quando foram analizados os grupos de idade diferentes segundo sexo, sugerindo maior importância relativa da transmissão na área peridoméstica nas mulheres e da transmissão na floresta subtropical nos homens. Espécimes de Lutzomyia intermedia, espécie já incriminada como vetor de Leishmaniose em outras províncias do norte da Argentina, foram capturadas e identificadas na localidade em maio de 1996. São analisadas as possíveis causas do surto relacionadas às variáveis climáticas e a abundância do vetor e os resultados são discutidas na estrutura de possíveis atividades de prevenção e

Leishmaniasis transmission in an ecotourism area: potential vectors in Ilha Grande, Rio de Janeiro State, Brazil.

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Carvalho, Bruno Moreira; Maximo, Michele; Costa, Wagner Alexandre; de Santana, Antonio Luís Ferreira; da Costa, Simone Miranda; da Costa Rego, Taiana Amancio Neves; de Pita Pereira, Daniela; Rangel, Elizabeth Ferreira

2013-11-13

island. The presence of L. (N.) flaviscutellata in peridomestic areas is also an important finding, since the species is involved in the transmission of diffuse cutaneous leishmaniasis. Health education practices directed to the local community and tourists are important control actions that can be taken in Ilha Grande to reduce the burden of leishmaniases.

Explaining variation in adult Anopheles indoor resting abundance: the relative effects of larval habitat proximity and insecticide-treated bed net use.

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McCann, Robert S; Messina, Joseph P; MacFarlane, David W; Bayoh, M Nabie; Gimnig, John E; Giorgi, Emanuele; Walker, Edward D

2017-07-17

Spatial determinants of malaria risk within communities are associated with heterogeneity of exposure to vector mosquitoes. The abundance of adult malaria vectors inside people's houses, where most transmission takes place, should be associated with several factors: proximity of houses to larval habitats, structural characteristics of houses, indoor use of vector control tools containing insecticides, and human behavioural and environmental factors in and near houses. While most previous studies have assessed the association of larval habitat proximity in landscapes with relatively low densities of larval habitats, in this study these relationships were analysed in a region of rural, lowland western Kenya with high larval habitat density. 525 houses were sampled for indoor-resting mosquitoes across an 8 by 8 km study area using the pyrethrum spray catch method. A predictive model of larval habitat location in this landscape, previously verified, provided derivations of indices of larval habitat proximity to houses. Using geostatistical regression models, the association of larval habitat proximity, long-lasting insecticidal nets (LLIN) use, house structural characteristics (wall type, roof type), and peridomestic variables (cooking in the house, cattle near the house, number of people sleeping in the house) with mosquito abundance in houses was quantified. Vector abundance was low (mean, 1.1 adult Anopheles per house). Proximity of larval habitats was a strong predictor of Anopheles abundance. Houses without an LLIN had more female Anopheles gambiae s.s., Anopheles arabiensis and Anopheles funestus than houses where some people used an LLIN (rate ratios, 95% CI 0.87, 0.85-0.89; 0.84, 0.82-0.86; 0.38, 0.37-0.40) and houses where everyone used an LLIN (RR, 95% CI 0.49, 0.48-0.50; 0.39, 0.39-0.40; 0.60, 0.58-0.61). Cooking in the house also reduced Anopheles abundance across all species. The number of people sleeping in the house, presence of cattle near the house

Oviposition ecology and species composition of Aedes spp. and Aedes aegypti dynamics in variously urbanized settings in arbovirus foci in southeastern Côte d'Ivoire.

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Zahouli, Julien B Z; Utzinger, Jürg; Adja, Maurice A; Müller, Pie; Malone, David; Tano, Yao; Koudou, Benjamin G

2016-09-29

Aedes mosquito-transmitted outbreaks of dengue and yellow fever have been reported from rural and urban parts of Côte d'Ivoire. The present study aimed at assessing Aedes spp. oviposition ecology in variously urbanized settings within arbovirus foci in southeastern Côte d'Ivoire. Aedes spp. eggs were sampled using a standard ovitrap method from January 2013 to April 2014 in different ecosystems of rural, suburban and urban areas. Emerged larvae were reared until the adult stage for species identification. Aedes spp. oviposition ecology significantly varied from rural-to-urban areas and according to the ecozones and the seasons. Species richness of Aedes spp. gradually decreased from rural (eight species) to suburban (three species) and urban (one species) areas. Conversely, emerged adult Aedes spp. mean numbers were higher in the urban (1.97 Aedes/ovitrap/week), followed by the suburban (1.44 Aedes/ovitrap/week) and rural (0.89 Aedes/ovitrap/week) areas. Aedes aegypti was the only species in the urban setting (100 %), and was also the predominant species in suburban (85.5 %) and rural (63.3 %) areas. The highest Ae. aegypti mean number was observed in the urban (1.97 Ae. aegypti/ovitrap/week), followed by the suburban (1.20 Ae. aegypti/ovitrap/week) and rural (0.57 Ae. aegypti/ovitrap/week) areas. Aedes africanus (9.4 %), Ae. dendrophilus (8.0 %), Ae. metallicus (1.3 %) in the rural, and Ae. vittatus (6.5 %) and Ae. metallicus (1.2 %) in the suburban areas each represented more than 1 % of the total Aedes fauna. In all areas, Aedes species richness and abundance were higher in the peridomestic zones and during the rainy season, with stronger variations in species richness in the rural and in abundance in the urban areas. Besides, the highest Culex quinquefasciatus abundance was found in the urban areas, while Eretmapodites chrysogaster was restricted to the rural areas. Urbanization correlates with a substantially higher abundance in Aedes mosquitoes and

A local outbreak of dengue caused by an imported case in Dongguan China

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Peng Hong-Juan

2012-01-01

Full Text Available Abstract Background Dengue, a mosquito-borne febrile viral disease, is found in tropical and sub-tropical regions around the world. Since the first occurrence of dengue was confirmed in Guangdong, China in 1978, dengue outbreaks have been reported sequentially in different provinces in South China transmitted by.peridomestic Ae. albopictus mosquitoes, diplaying Ae. aegypti, a fully domestic vector that transmits dengue worldwide. Rapid and uncontrolled urbanization is a characteristic change in developing countries, which impacts greatly on vector habitat, human lifestyle and transmission dynamics on dengue epidemics. In September 2010, an outbreak of dengue was detected in Dongguan, a city in Guangdong province characterized by its fast urbanization. An investigation was initiated to identify the cause, to describe the epidemical characteristics of the outbreak, and to implement control measures to stop the outbreak. This is the first report of dengue outbreak in Dongguan, even though dengue cases were documented before in this city. Methods Epidemiological data were obtained from local Center of Disease Control and prevention (CDC. Laboratory tests such as real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR, the virus cDNA sequencing, and Enzyme-Linked immunosorbent assay (ELISA were employed to identify the virus infection and molecular phylogenetic analysis was performed with MEGA5. The febrile cases were reported every day by the fever surveillance system. Vector control measures including insecticidal fogging and elimination of habitats of Ae. albopictus were used to control the dengue outbreak. Results The epidemiological studies results showed that this dengue outbreak was initiated by an imported case from Southeast Asia. The outbreak was characterized by 31 cases reported with an attack rate of 50.63 out of a population of 100,000. Ae. albopictus was the only vector species responsible for the outbreak. The virus c

Risk Zone Modelling and Early Warning System for Visceral Leishmaniasis Kala-Azar Disease in Bihar, India Using Remote Sensing and GIS

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Jeyaram, A.; Kesari, S.; Bajpai, A.; Bhunia, G. S.; Krishna Murthy, Y. V. N.

2012-07-01

Visceral Leishmaniasis (VL) commonly known as Kala-azar is one of the most neglected tropical disease affecting approximately 200 million poorest populations 'at risk in 109 districts of three endemic countries namely Bangladesh, India and Nepal at different levels. This tropical disease is caused by the protozoan parasite Leishmania donovani and transmitted by female Phlebotomus argentipes sand flies. The analysis of disease dynamics indicate the periodicity at seasonal and inter-annual temporal scale which forms the basis for development of advanced early warning system. Study area of highly endemic Vaishali district, Bihar, India has been taken for model development. A Systematic study of geo-environmental parameters derived from satellite data in conjunction with ground intelligence enabled modelling of infectious disease and risk villages. High resolution Indian satellites data of IRS LISS IV (multi-spectral) and Cartosat-1 (Pan) have been used for studying environmentally risk parameters viz. peri-domestic vegetation, dwelling condition, wetland ecosystem, cropping pattern, Normalised Difference Vegetation Index (NDVI), detailed land use etc towards risk assessment. Univariate analysis of the relationship between vector density and various land cover categories and climatic variables suggested that all the variables are significantly correlated. Using the significantly correlated variables with vector density, a seasonal multivariate regression model has been carried out incorporating geo-environmental parameters, climate variables and seasonal time series disease parameters. Linear and non-linear models have been applied for periodicity and interannual temporal scale to predict Man-hour-density (MHD) and 'out-of-fit' data set used for validating the model with reasonable accuracy. To improve the MHD predictive approach, fuzzy model has also been incorporated in GIS environment combining spatial geo-environmental and climatic variables using fuzzy membership

Studies on sand fly fauna and ecological analysis of Phlebotomus orientalis in the highland and lowland foci of kala-azar in northwestern Ethiopia.

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Esayas Aklilu

Full Text Available Visceral leishmaniasis (VL also known as kala-azar is a growing health problem in Ethiopia with an estimated annual VL incidence between 3700 and 7400. The disease is mainly endemic in northwestern parts of the country. The aim of the current study was to determine the sand fly fauna and ecology of Phlebotomus orientalis in two endemic and ecologically distinct areas of northwestern Ethiopia.Sand flies were collected using CDC light traps, sticky traps and pyrethrum spray catches from peri-domestic, mixed forest, farm field and indoor habitats from both Libo-Kemkem (May 2011-April 2012 and Metema (October 2012-September 2013 districts.A total of 51,411 sand fly specimens were collected and identified (10,776 from highland and 40, 635 from the lowland areas. Seven species were found in the highland area: two Phlebotomus spp. (P. orientalis and P. rodhaini and five Sergentomyia species. Whereas 19 species were found in the lowland area: six Phlebotomus (P. orientalis, P. rodhaini, P. bergeroti, P. duboscqi, P. papatasi and P. martini and 13 Sergentomyia species. Of the Phlebotomus spp., P. orientalis was the predominant species in both the highland (99.9% and lowland (93.7% areas. Indoor collections using pyrethrum spray catches and sticky traps indicated that P. orientalis has a strong exophilic and exophagic behaviors in both districts. In both areas, this species showed seasonal occurrence and showing abundance during the dry months (March-May/June of the year and increasing in numbers till the rain season, when numbers dropped dramatically. Mean density of P. orientalis in the two areas had positive and significant correlation with mean temperature in light trap collections (P0.05. Regarding the rainfall pattern, density of P. orientalis had negative and statistically insignificant correlation (for light trap collections for both areas and significant correlation (for sticky trap collections for lowland area.The current study indicated the

NOTE TASSONOMICHE E NOMENCLATORIALI SU ALCUNE SPECIE PALEARTICHE DI SIBINIA E TYCHIUS (COLEOPTERA, CURCULIONIDAE

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Roberto Caldara

2009-10-01

Full Text Available In accordo con le disposizioni del codice internazionale di Nomenclatura Zoologica, vengono proposte otto azioni allo scopo di salvaguardare la stabilità della nomenclatura attuale di alcune specie della tribù Tychiini. seguendo le indicazioni dell’Articolo 23.9.1, Sibinia subelliptica Desbrochers, 1873 è considerato nomen protectum e Gymnetron schaumi Becker, 1864 è considerato nomen oblitum; Sibinia phalerata Gyllenhal, 1836 è considerato nomen protectum e Sibinia centromaculata Villa & Villa, 1835 è considerato nomen oblitum. Essendo presenti le condizioni richieste dall’articolo 75.3, vengono designati i neotipi dei seguenti taxa: Sibinia centromaculata Villa & Villa, 1835; Sybines pulchellus Desbrochers, 1875. Sono inoltre stabiliti i lectotypi di: Gymne­ tron schaumi Becker, 1864; Sibinia attalica Gyllenhal var. lateralis Desbrochers, 1895; Sibinia cinctella Desbrochers, 1898; Sibinia pozuelica Fuente, 1910; Tychius barceloni­cus Desbrochers, 1908; Tychius edentatus Desbrochers, 1895; Tychius pallidicornis Desbrochers, 1875; Tychius parvulus Stephens, 1831; Tychius seductor Desbrochers, 1908. Vengono proposte le seguenti nuove sinonimie: Sibinia bipunctata Kirsch, 1870 = Sibi­nia postsignata Voss, 1971 n. syn.; Sibinia exigua Faust = Sibinia cinctella Desbrochers, 1898 n. syn.; Sibinia femoralis Germar, 1824 = Sibinia attalica var. lateralis Desbrochers, 1895 n. syn. = Sibinia consanguinea Desbrochers, 1895 n. syn. = Sibinia attalica var. curtula Desbrochers, 1907 n. syn. = Sibinia dilataticollis Desbrochers, 1907 n. syn.= Sibinia seducta Desbrochers, 1907 n. syn. = Sibinia pozuelica Fuente, 1910 n. syn.; Si­binia pici Desbrochers = Sibinia otiosa Hustache, 1944 n. syn. = Sibinia praeventa Hustache, 1944 n. syn.; Sibinia subelliptica Desbrochers, 1873 = Sibinia schaumei Desbrochers, 1895 n. syn.; Sibinia unicolor Fåhraeus, 1843 = Sybines pulchellus Desbrochers, 1875 n. syn. = Sibinia ochreata Schilsky, 1912 n. syn

Area-wide control of Chagas disease vectors in Latin America

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Schofield, C.J.

2000-01-01

Argentina, Brazil and Venezuela. Without exception, the results followed a similar course, with a rapid decline in house infestation rates and a reduction in the incidence of human infection. Generally however, it was impossible to consolidate the initial successes due to changes in intervention policy and a corresponding lack of programme continuity. Although domestic populations of Triatomine bugs can be cleared from individual houses, or from particular localities, the houses remain vulnerable to re-infestation by bugs brought in from untreated regions. In Brazil, the national programme to eliminate the primary vector, Triatoma infestans (Klug), was launched in 1983. It was highly successful, but - as with previous local campaigns - there were problems of sustainability and re-infestation of many of the treated localities (Dias 1987). To address this problem, governments of the six southern cone countries (Argentina, Bolivia, Brazil, Chile, Paraguay and Uruguay) in 1991 set up a joint initiative to control Chagas disease through the elimination of all domestic and peridomestic populations of the triatomine vectors (Kingman 1991). With the addition of Peru to this programme in 1996, the initiative now covers the entire geographic distribution of the primary vector, T. infestans. The Southern Cone Initiative was planned as a 10-year programme to eliminate all domestic and peridomestic populations of T. infestans, with concurrent suppression of other vector species of local importance. Now just past its mid-point, the programme has already met with considerable success with Chagas disease transmission interrupted over vast areas of Argentina, Chile, Uruguay, central Brazil, eastern Paraguay and southern Bolivia (Schmunis et al. 1996, WHO 1996, 1997a, 1998). Other domestic vectors in the region - such as Triatoma brasiliensis Neiva in northeast Brazil - are also being controlled and the World Health Organisation (WHO) now predicts complete interruption of Chagas disease

Caracterização fitofisionômica e levantamento florístico preliminar no Pantanal dos Rios Mortes-Araguaia, Cocalinho, Mato Grosso, Brasil Vegetation types and preliminary floristic survey in the Mortes-Araguaia Pantanal, Cocalinho, Mato Grosso, Brazil

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Beatriz Schwantes Marimon

2001-08-01

the Cristalino river (12° 52'S; 50° 49'W. Sampling was by the Rapid Survey method. Eight vegetation types were identified: Mata Inundável (swamp forest, Caapão (also swamp forest, Babaçual (Attalea speciosa forest, Cerradão, Cerrado stricto sensu (savanna types, closed canopy woodland and savanna grassland, respectively, Campo de Murunduns (grassland with scattered mounds bearing termites, Campo de Byrsonima orbignyana (grassland dominated by B. orbignyana and Campo Cerrado de Vochysia rufa (grassland with scattered trees of V. rufa. A total of 248 species of trees, shrubs and lianas were recorded, distributed in 158 genera and 62 families. The vegetation types were heterogeneous; none of the species occurred at all sites, but Alibertia edulis (L. Rich. A. Rich., Andira cuyabensis Benth., Maprounea guianensis (Aubl. M. Arg., and others, were found at six sites. The families richest in species were Caesalpiniaceae, Annonaceae and Myrtaceae. The flora apparently was similar to that of the Pantanal of Paraguai river, however, further studies are needed to confirm. This Heterogeneous vegetation patterns in the study area indicate the need to protect the Pantanal of the Mortes and Araguaia rivers.

Environmental intervention as a tool for control of schistosomiasis: suggestions from a field study in Northeast Brazil Controle da esquistossomose mediante emprego de medidas ambientais: sugestões a partir de um estudo de campo no nordeste brasileiro

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Kurt Kloetzel

Full Text Available The present survey from the State of Alagoas (Brazil emphasized, once again, the importance of peridomestic or neighbourhood foci in the transmission of schistosomiasis mansoni. Although the study area consisted of a compact and densely populated urban community (Bairro Frio, União dos Palmares county, prevalence as well as the distribution of high egg counts was quite patchy, exhibiting a spatial pattern correlated with the distribution of ditches and other small-sized collections of surface water. Despite the availability of satisfactory water supply in most households, as well as the absence of any major body of water capable of furthering transmission, egg counts in Bairro Frio exceeded any other in our previous experience. Morbidity, however, appeared to be insignificant, a trend which has been observed over the last decade in several other highly endemic areas. It appears clear to the authors that the control of transmission requires investment in environmental intervention and that this proposal, far from being utopic, can be furthered by quite modest means and through the participation of community or neighbourhood groups.O presente estudo, realizado no Estado de Alagoas, mais uma vez demonstrou o papel relevante dos focos peridomiciliares ou de vizinhança na transmissão da esquistossomose. Embora se trate de uma área urbana, compacta e densamente povoada (Bairro Frio, município de União dos Palmares, a distribuição tanto da prevalência como dos indivíduos com contagem de ovos elevada nas fezes obedeceu a nítido padrão espacial, altamente correlacionado com a distribuição de valetas de drenagem e outras pequenas coleções de água. Embora a maioria dos habitantes tenha acesso a água potável e, não obstante a ausência de coleções de água de algum vulto, capazes de manter a transmissão, a intensidade das contagens de ovos superou quaisquer dados anteriormente obtidos em outras áreas. Ainda assim, a morbidade mostrou

Ecologia domestica de la tripanosomiasis americana: perfil alimentario del triatoma infestans en un area rural de la província de Santiago del Estero, Argentina

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Cristina Wisnivesky-Colli

1987-03-01

peridomestic structures harboured bugs. T. cruzi infection was detected in 39% of domiciliary. T. infestans 96% of the domiciliary bugs (9 6% f e d on man, dog, chicken and cat. The affinity index fo r dog was 13 times higher than that for man. The importance of the high density of T. infestans bugs in bedrooms and their close association with "roommate ” dogs is discussed in relation to transmission as well as the need to combine house improvement and health education programmes.

The ecology of Triatoma sordida in natural environments in two different regions of the state of Minas Gerais, Brazil Ecologia do Triatoma sordida no ambiente silvestre de duas diferentes regiões do estado de Minas Gerais, Brasil

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L. Diotaiuti

1993-06-01

Full Text Available A study was undertaken about T. sordida in the natural environment in two different regions of the state of Minas Gerais: Itapagipe (Triângulo, an area of cerrado modified by the formation of fields of pasture and agriculture, and Mato Verde (north an area of transition between caatinga and cerrado with profound deforestation in the last years due to the expansion of cotton cultivation. In both regions the principal ecotopes identified were hollow trees and the bark of live or dead trees, where the occurrence of a food source is not frequent. In this environment, the triatomines utilize various food sources; opposums appear to represent an important source of infection. In the north of Minas, a greater concentration of reservoirs and vectors was observed than in the Triángulo which could explain the higher level of infection of the triatomines in the north. Close attention to the process of domiciliation of T. sordida in the north of Minas is recommended where an extensive intervention by man in the natural environment has occurred and where a rise in the population of triatomines in the peridomestic environment has been observed in recent years.Foi realizado um estudo sobre o T. sordida em ambiente silvestre em duas diferentes regiões do estado de Minas Gerais: Itapagipe (Triângulo, área de cerrado modificado para formação de campos de pastagem e agricultura, e Mato Verde (norte uma área de transição entre a caatinga e o cerrado, profundamente desmatada nos últimos anos com a finalidade de expansão do cultivo de algodão. Em ambas as regiões, os principais ecotopos identificados corresponderam a buracos e cascas de árvores vivas ou mortas, onde a ocorrência de fontes de alimentação não é frequente. Neste ambiente, os triatomíneos utilizam-se de variadas fontes de alimentação; gambás parecem representar urna importante fonte de infecção. No norte de Minas, observou-se urna maior concentração de reservatórios e vetores

Dengue vector management using insecticide treated materials and targeted interventions on productive breeding-sites in Guatemala

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Rizzo Nidia

2012-10-01

households, tropical rains occurred in the area and lead to an increase of the vector population, more pronounced (but statistically not significant in the control arm than in the intervention arm. In the second intervention (17 months later and six weeks after implementing the second intervention the combined approach of ITMs and a combination of appropriate interventions against productive containers (Temephos in >200 L water drums, elimination of small discarded tins and bottles lead to significant differences on reductions of the total number of pupae (P = 0.04 and the House index (P = 0.01 between intervention and control clusters, and to borderline differences on reductions of the Pupae per Person and Breteau indices (P = 0.05. The insecticide residual activity on treated curtains was high until month 18 but the chemical concentration showed a high variability. The cost per house protected with treated curtains and drum covers and targeting productive breeding-sites of the dengue vector was $ 5.31 USD. The acceptance of the measure was generally high, particularly in families who had experienced dengue. Conclusion Even under difficult environmental conditions (open houses, tropical rainfall, challenging container types mainly in the peridomestic environment the combination of insecticide treated curtains and to a less extent drum covers and interventions targeting the productive container types can reduce the dengue vector population significantly.

Dengue vector management using insecticide treated materials and targeted interventions on productive breeding-sites in Guatemala.

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Rizzo, Nidia; Gramajo, Rodrigo; Escobar, Maria Cabrera; Arana, Byron; Kroeger, Axel; Manrique-Saide, Pablo; Petzold, Max

2012-10-30

lead to an increase of the vector population, more pronounced (but statistically not significant) in the control arm than in the intervention arm. In the second intervention (17 months later and six weeks after implementing the second intervention) the combined approach of ITMs and a combination of appropriate interventions against productive containers (Temephos in >200 L water drums, elimination of small discarded tins and bottles) lead to significant differences on reductions of the total number of pupae (P = 0.04) and the House index (P = 0.01) between intervention and control clusters, and to borderline differences on reductions of the Pupae per Person and Breteau indices (P = 0.05). The insecticide residual activity on treated curtains was high until month 18 but the chemical concentration showed a high variability. The cost per house protected with treated curtains and drum covers and targeting productive breeding-sites of the dengue vector was $ 5.31 USD. The acceptance of the measure was generally high, particularly in families who had experienced dengue. Even under difficult environmental conditions (open houses, tropical rainfall, challenging container types mainly in the peridomestic environment) the combination of insecticide treated curtains and to a less extent drum covers and interventions targeting the productive container types can reduce the dengue vector population significantly.

PCR reveals significantly higher rates of Trypanosoma cruzi infection than microscopy in the Chagas vector, Triatoma infestans: High rates found in Chuquisaca, Bolivia

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Lucero David E

2007-06-01

Full Text Available Abstract Background The Andean valleys of Bolivia are the only reported location of sylvatic Triatoma infestans, the main vector of Chagas disease in this country, and the high human prevalence of Trypanosoma cruzi infection in this region is hypothesized to result from the ability of vectors to persist in domestic, peri-domestic, and sylvatic environments. Determination of the rate of Trypanosoma infection in its triatomine vectors is an important element in programs directed at reducing human infections. Traditionally, T. cruzi has been detected in insect vectors by direct microscopic examination of extruded feces, or dissection and analysis of the entire bug. Although this technique has proven to be useful, several drawbacks related to its sensitivity especially in the case of small instars and applicability to large numbers of insects and dead specimens have motivated researchers to look for a molecular assay based on the polymerase chain reaction (PCR as an alternative for parasitic detection of T. cruzi infection in vectors. In the work presented here, we have compared a PCR assay and direct microscopic observation for diagnosis of T. cruzi infection in T. infestans collected in the field from five localities and four habitats in Chuquisaca, Bolivia. The efficacy of the methods was compared across nymphal stages, localities and habitats. Methods We examined 152 nymph and adult T. infestans collected from rural areas in the department of Chuquisaca, Bolivia. For microscopic observation, a few drops of rectal content obtained by abdominal extrusion were diluted with saline solution and compressed between a slide and a cover slip. The presence of motile parasites in 50 microscopic fields was registered using 400× magnification. For the molecular analysis, dissection of the posterior part of the abdomen of each insect followed by DNA extraction and PCR amplification was performed using the TCZ1 (5' – CGA GCT CTT GCC CAC ACG GGT GCT – 3

Phlebotominae fauna in the Province of Tucumán, Argentina Fauna flebotomínica en la Provincia de Tucumán, Argentina

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Elizabeth CÓRDOBA LANÚS

2002-02-01

Full Text Available American Tegumentary Leishmaniasis is endemic in the province of Tucumán since 1916 where the first Argentinian case of leishmaniasis was reported. An epidemic outbreak took place in the province during 1986-1988, after that the number of cases increased gradually again between 1991-1996. Since October of 1999 sand flies captures were performed at different places associated with current and past transmission or sites identified as risky ones. The collections were carried out with CDC mini light trap and modified Shannon trap. In this study 2338 Phlebotominae were captured being prevalent Lutzomyia neivai (Lu intermedia complex (97.7%, followed by Lu. migonei. We report Lu. shannoni for the first time in the province. Phlebotominae was abundant in the warm and humid months and showed a peak before the summer rains. Lutzomyia neivai showed a pattern (peridomestic prevalence, anthropophilia, abundance in secondary forest consistent with other outbreak studies. Thus, the results reinforce this species incrimination as vector of leishmaniasis in the area. Domestic animals close to houses increase its abundance, and so the probable associated risk of human-Phlebotominae contact. Further studies should be done to understand the role of each Phlebotominae species in the transmission of leishmaniasis in Tucumán in order to design entomological surveillance strategies.La Leishmaniasis Tegumentaria Americana es endémica en la provincia de Tucumán desde 1916, lugar donde se reportara el primer caso argentino de leishmaniasis. Entre 1986-88 ocurrió un brote epidémico en la provincia, después de este hecho el número de casos aumentó en forma gradual nuevamente entre los años 1991-1996. A partir de Octubre de 1999 se realizaron capturas de Phlebotominae en la provincia en diferentes sitios asociados con transmisión actual o pasada de leishmaniasis o en aquellos sitios identificados como de riesgo. Los muestreos se llevaron a cabo con mini trampa de

Chagas disease risk in Texas.

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Sarkar, Sahotra; Strutz, Stavana E; Frank, David M; Rivaldi, Chissa-Louise; Sissel, Blake; Sánchez-Cordero, Victor

2010-10-05

Chagas disease, caused by Trypanosoma cruzi, remains a serious public health concern in many areas of Latin America, including México. It is also endemic in Texas with an autochthonous canine cycle, abundant vectors (Triatoma species) in many counties, and established domestic and peridomestic cycles which make competent reservoirs available throughout the state. Yet, Chagas disease is not reportable in Texas, blood donor screening is not mandatory, and the serological profiles of human and canine populations remain unknown. The purpose of this analysis was to provide a formal risk assessment, including risk maps, which recommends the removal of these lacunae. The spatial relative risk of the establishment of autochthonous Chagas disease cycles in Texas was assessed using a five-stage analysis. 1. Ecological risk for Chagas disease was established at a fine spatial resolution using a maximum entropy algorithm that takes as input occurrence points of vectors and environmental layers. The analysis was restricted to triatomine vector species for which new data were generated through field collection and through collation of post-1960 museum records in both México and the United States with sufficiently low georeferenced error to be admissible given the spatial resolution of the analysis (1 arc-minute). The new data extended the distribution of vector species to 10 new Texas counties. The models predicted that Triatoma gerstaeckeri has a large region of contiguous suitable habitat in the southern United States and México, T. lecticularia has a diffuse suitable habitat distribution along both coasts of the same region, and T. sanguisuga has a disjoint suitable habitat distribution along the coasts of the United States. The ecological risk is highest in south Texas. 2. Incidence-based relative risk was computed at the county level using the Bayesian Besag-York-Mollié model and post-1960 T. cruzi incidence data. This risk is concentrated in south Texas. 3. The

Chagas disease risk in Texas.

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Sahotra Sarkar

Full Text Available BACKGROUND: Chagas disease, caused by Trypanosoma cruzi, remains a serious public health concern in many areas of Latin America, including México. It is also endemic in Texas with an autochthonous canine cycle, abundant vectors (Triatoma species in many counties, and established domestic and peridomestic cycles which make competent reservoirs available throughout the state. Yet, Chagas disease is not reportable in Texas, blood donor screening is not mandatory, and the serological profiles of human and canine populations remain unknown. The purpose of this analysis was to provide a formal risk assessment, including risk maps, which recommends the removal of these lacunae. METHODS AND FINDINGS: The spatial relative risk of the establishment of autochthonous Chagas disease cycles in Texas was assessed using a five-stage analysis. 1. Ecological risk for Chagas disease was established at a fine spatial resolution using a maximum entropy algorithm that takes as input occurrence points of vectors and environmental layers. The analysis was restricted to triatomine vector species for which new data were generated through field collection and through collation of post-1960 museum records in both México and the United States with sufficiently low georeferenced error to be admissible given the spatial resolution of the analysis (1 arc-minute. The new data extended the distribution of vector species to 10 new Texas counties. The models predicted that Triatoma gerstaeckeri has a large region of contiguous suitable habitat in the southern United States and México, T. lecticularia has a diffuse suitable habitat distribution along both coasts of the same region, and T. sanguisuga has a disjoint suitable habitat distribution along the coasts of the United States. The ecological risk is highest in south Texas. 2. Incidence-based relative risk was computed at the county level using the Bayesian Besag-York-Mollié model and post-1960 T. cruzi incidence data. This

Factors associated with Leishmania chagasi infection in domestic dogs from Teresina, State of Piauí, Brazil Fatores associados à infecção por Leishmania chagasi em cães domiciliados de Teresina, Estado do Piauí, Brasil

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João Pereira da Silva

2012-08-01

Full Text Available INTRODUCTION: Many studies have evaluated risk factors for human visceral leishmaniasis, but few have focused on the infection among dogs. The objective of this study was to assess the association between peridomestic socioeconomic and environmental factors and the presence of dogs seropositive for Leishmania chagasi in the City of Teresina, Brazil. METHODS: This case-control study was based on the results of a routine seroepidemiological survey among domestic dogs carried out in 2007. Serological tests were performed by means of indirect immunofluorescence antibody test. All dwellings in which at least one seropositive dog was detected were considered cases, and controls were a random sample of dwellings in which only seronegative dogs were identified. Associations between variables were expressed as odds ratios (OR and their respective 95% confidence intervals (95%CI estimated using multivariate logistic regression. RESULTS: Dwellings with a history of dogs removed by the visceral leishmaniasis control program in the last 12 months had five-fold higher odds of having at least one seropositive dog as compared with dwellings having no history of dog removal (OR = 5.19; 95%CI = 3.20-8.42. Dwellings with cats had 58% increased odds of dog infection as compared with those having no cats (OR = 1.58; 95%CI = 1.01-2.47. CONCLUSIONS: Identification of factors associated with canine visceral leishmaniasis might be used for the delimitation of areas of higher risk for human visceral leishmaniasis, since infection in dogs generally precedes the appearance of human cases.INTRODUÇÃO: Diversos estudos avaliaram fatores de risco para leishmaniose visceral humana, mas poucos focalizaram a infecção canina. O objetivo deste estudo é avaliar a associação entre condições sócio-ambientais peridomiciliares e a presença de cães sorologicamente positivos para Leishmania chagasi em Teresina, Brasil. MÉTODOS: Estudo caso-controle baseado nos resultados de

Enzootic transmission of Trypanosoma cruzi and T. rangeli in the Federal District of Brazil Transmissão enzoótica de Trypanosoma cruzi e T. rangeli no Distrito Federal, Brasil

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Rodrigo Gurgel-Gonçalves

2004-04-01

Full Text Available The Federal District of Brazil (DF lies within the Cerrado biome, where open shrubland (savannas is interspersed with riverside gallery forests and permanent swamps (veredas. Trypanosoma cruzi-infected native triatomines occur in the area, but the enzootic transmission of trypanosomatids remains poorly characterized. A parasitological survey involving sylvatic triatomines (166 Rhodnius neglectus collected from Mauritia flexuosa palms and small mammals (98 marsupials and 70 rodents, totaling 18 species was conducted in 18 sites (mainly gallery forests and veredas of the DF. Parasites were isolated, morphologically identified, and characterized by PCR of nuclear (mini-exon gene and kinetoplast DNA (kDNA. Six R. neglectus, seven Didelphis albiventris and one Akodon cursor were infected by trypanosomes; wild reservoir infection is documented for the first time in the DF. kDNA PCR detected T. cruzi in five R. neglectus and mini-exon gene PCR revealed T. cruzi I in isolates from D. albiventris. Parasites infecting one bug yielded T. rangeli KP1+ kDNA amplicons. In spite of the occurrence of T. cruzi-infected D. albiventris (an important wild and peridomestic reservoir and R. neglectus (a secondary vector displaying synanthropic behavior, a low-risk of human Chagas disease transmission could be expected in the DF, considering the low prevalence infection recorded in this work. The detection of T. rangeli KP1+ associated with R. neglectus in the DF widens the known range of this parasite in Brazil and reinforces the hypothesis of adaptation of T. rangeli populations (KP1+ and KP1- to distinct evolutionary Rhodnius lineages.O Distrito Federal (DF do Brasil está localizado no bioma Cerrado, um complexo de fisionomias savânicas incluindo matas de galeria e campos úmidos permanentes (veredas. Triatomíneos silvestres infectados por Trypanosoma cruzi ocorrem na área, mas a transmissão enzoótica de tripanossomatídeos permanece insuficientemente

Efecto de la alternación de fuentes sanguíneas sobre la fecundidad y la fertilidad de Rhodnius prolixus Stal (Heteroptera: Reduviidae

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Elis José Aldana

2009-04-01

Full Text Available En este trabajo se evidencia que si el éxito reproductivo de Rhodnius prolixus Stal está relacionado a la fuente alimentaria, entonces las necesidades biológicas del insecto son satisfechas en modos diferentes según el tipo de alternancia entre dichas fuentes de alimentación; tales diferencias son reveladas mediante los cambios en fertilidad y fecundidad del insecto. Se realizaron nueve alternancias, en cada una se suministraron dos alimentaciones, en unas se alternó la fuente de alimentación y en los controles se suministraron dos alimentaciones con la misma fuente. Las fuentes alimentarias fueron paloma, gallina y humano, esta última mediante un aparato de alimentación artificial; estas fuentes se escogieron en el supuesto que son fuentes alimentarias encontradas en los ecotopos silvestre, peri-domicilio y domicilio respectivamente. En todos los tipos de alternancia se encontró una relación lineal entre la fecundidad y el tiempo de oviposición, que la relación entre cantidad de sangre ingerida y la fecundidad varían, que la tasa de fecundidad aumenta en la segunda alimentación respecto a la primera y que la fertilidad fue superior al 95 %. Effects of alternating blood sources on fecundity and fertility of Rhodnius prolixus Stal (Heteroptera: ReduviidaeIn this work it is argued that if the reproductive parameters of Rhodnius prolixus Stal are related to the blood source upon which it feeds, then the insects biological needs must be satisfied in different ways by the alternation between blood sources, reveled through changes in the fecundity and fertility of individuals of this insect species. Nine experiments were conducted, each one consisting of two feedings, in which the blood source were either alternated or remained the same. The meal sources used were pigeon, hen and human blood, selected according to the resources found in the sylvatic, peri-domestic and domestic ecotopes respectively. It was found that the quantity of

Territorialidades, lived and senses of place in advance of the productive frontier times spaces Territorialidades, espacios vividos y sentidos de lugar en tiempos de avance de la frontera productiva

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María Eugenia Comerci

2010-01-01

Full Text Available In full process redshift the productive border and pop-up dispute over the use and appropriation of resources, the intervention of different social subjects in the West of La Pampa is redefining productivas-reproductivas practices crianceros farmers and, consequently, the social construction of space. Since the end of the military campaigns against agents, different indigenous societies through the exercise of power, built certain territorial representations and put into action practices tending to articulate the pampean West with the national economy. However little appreciation of this space made possible the development of certain forms of organizing socio-productive and symbolic autonomy. Before the expansion of the livestock border, the imposed hydrocarbon region and increasing presence of new territorial logics grow confrontations by unequal access to natural resources, the appropriation of space and the construction of territorialidades. In this context, article focused on the internal organisation of rural settlements and social uses of spaces of time, in two areas of the West "end" look: La Humada and Chos Malal. This mode is intended to establish how organized spaces home, peridomestic and mount and what senses expressed subjects into life and places spaces in times of expansion of the production frontier. The new social field generated product of capitalism on the peasant drives progress is expressed, not only changes in forms of livestock, management organization of production and social construction of space, but also in forms of sociability and collective resistance strategies. This process, which is brewing in the region, has a similar development in other spaces where productive progress has occurred before or at a faster pace. Different qualitative methodology strategies that combine the study case with life stories, in-depth interviews and analysis of documentary sources are articulated for the conduct of research.En pleno

Inter-relações entre os ciclos de transmissão do Trypanosoma cruzi no município de Bambuí, Minas Gerais, Brasil Relationships between Trypanosoma cruzi transmission cycles in the county of Bambuí, Minas Gerais, Brazil

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Alexandre José Fernandes

1994-12-01

represents an important link between the sylvatic and intradomestic environments serving as a carrier of Z1 T. cruzi and maintaining the transmission cycles of Z2 T. cruzi in the peridomestic and intradomestic environments thus providing the potential for a gradual reinfestation of the county if the "Epidemiological Surveillance" is interrupted.