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In this paper, the overall morphological differences between populations of Simulium subpallidum Lutz, 1909 are studied. Several studies found in the literature point to a relationship between the labral fans and body size and the habitat where blackfly larvae occur. However, other characteristics potentially related to the microhabitat, such as abdominal hook circlet morphology, which is used for larvae to fix themselves in the substratum, and thoracic prolegs morphology, which help larvae move in the substratum, were analyzed in three different populations of S. subpallidum, one of which occupied a faster flow. The results suggest phenotypic plasticity in S. subpallidum and a tendency toward larger structures in faster flows. Keywords: Microhabitat associations, Neotropical region, Simuliidae, Water current range

INTRODUCTION: This study analyzed blackfly awareness and perceptions of health education practices for blackfly control among vulnerable populations in Brazil. METHODS: An exploratory descriptive quantitative research analysis was performed to investigate and analyze the awareness of and potential participation in blackfly control measures by vulnerable populations. RESULTS: Countryside resident participants (n = 24/38; 63.2% of the total sample) reported that blackflies were an obstacle to the performance of their work activities. CONCLUSIONS: Blackflies are a public health problem, and actions for blackfly control have been carried out without social participation or educational health practices that involve proper community knowledge.

We investigated the spatial and temporal distribution of blackfly larvae on a mesohabitat scale atfour different breeding sites in the Brazilian savannah "Cerrado." A total of 2,385 larvae of 12 different species were collected, and three of the sampling sites revealedspecies richness and diversity peaks in April. A principal components analysis was performed to reduce abiotic data into a smaller set of independent variables, such as precipitation and river size, and subsequent linear regressions showed that Simulium subpallidum was positively correlated with precipitation. This species, along with S. nigrimanum, was negatively correlated withriver size, whereasS. perflavum was negatively correlated with precipitation. Beta diversity was negatively correlated withprecipitation, and black fly taxocenoses were markedly different between wet and dry seasons, as shown through nonmetric multidimensional scaling, suggesting that precipitation playsa major role in structuring these communities, probably because of enhanced drift and the dendritic nature of lotic metacommunities.

Mansonella ozzardi infections are common in the riverside communities along the Solimoes, Negro and Purus Rivers in the state of Amazonas (AM). However, little is known about the presence of this parasite in communities located in regions bordering AM and the state of Acre. The prevalence rate of M. ozzardi infections was determined in blood samples from volunteers according to the Knott method. A total of 355 volunteers from six riverine communities were enrolled in the study and 65 (18.3%) were found to be infected with M. ozzardi. As expected, most of the infections (25%) occurred in individuals involved in agriculture, cattle rearing and fishing and an age/sex group analysis revealed that the prevalence increased beginning in the 40-50-years-of-age group and reached 33% in both sexes in individuals over 50 years of age. Based on the described symptomatology, articular pain and headache were found to be significantly higher among infected individuals (56 and 65% prevalence, respectively, p < 0.05). Sera from volunteers were subjected to ELISA using a cocktail of recombinant proteins from Onchocerca volvulus to evaluate the specificity of the test in an endemic M. ozzardi region. No cross-reactions between M. ozzardi-infected individuals and recombinant O. volvulus proteins were detected, thus providing information on the secure use of this particular cocktail in areas where these parasites are sympatric.

A new species of Simuliidae, Simulium (Chirostilbia) brunnescens, was discovered at Chapada dos Guimarães, state of Mato Grosso, Brazil, and nearby municipalities (Paranatinga, Rosário do Oeste and Nobres). This species is described here based on the adults, pupae and larvae. This species is closely related to Simulium (C.) subpallidum Lutz, but could be differentiated in all stages: females, leg colour pattern and frontal dilatation size; males, gonostyle shape; pupae, number of gill filaments; larvae, body size and colour, postgenal cleft, ratio between antenna and stalk of labral fan.

Recently, knowledge of Neotropical Simuliidae has been accumulating quickly. However, information about supra-specific relationships is scarce and diagnoses of Simulium subgenera are unsatisfactory. To investigate the relationships among Simulium (Chirostilbia) species and test the subgenus monophyly, we performed a cladistic analysis. The ingroup included all species of this subgenus and the outgroup included representatives of the 17 species groups of Neotropical Simulium and three Holarctic species. The study was based on a data matrix with 31 terminal taxa and 45 morphological characteristics of adult, pupa and larva. The phylogenetic analysis under equal weights resulted in eight most-parsimonious trees (length = 178, consistency index = 34, retention index = 67). The monophyly of the S. (Chirostilbia) was not supported in our analysis. The Simulium subpallidum species group was closer to Simulium (Psilopelmia) and Simulium (Ectemnaspis) than to the Simulium pertinax species group. Additionally, we describe the three-dimensional shape of the terminalia of male and female of Simulium (Chirostilbia) for the first time and provide comments about the taxonomic problems involving some species of the subgenus: Simulium acarayense, Simulium papaveroi, S. pertinax, Simulium serranum, Simulium striginotum and S. subpallidum.

The Simuliidae fauna from the Santa Catarina state, Brazil, was documented, based primarily on specimens deposited in the collections of the Instituto Oswaldo Cruz, Brazil and the La Plata Museum, Argentina. The results of our survey are organized by mesoregion and by municipality. Of the 51 municipalities where black flies were recorded, 46 represented new unpublished locality records. A total of 29 species belonging to two genera and eight subgenera were found, among which five are new records for the Santa Catarina state. The species recorded are (new records are marked with a *): Lutzsimulium hirticosta, Simuliium (Chirostilbia) acarayense, S. (Chirostilbia) distinctum, S. (Chirostilbia) empascae, S. (Chirostilbia) pertinax, S. (Chirostilbia) riograndense, S. (Chirostilbia) subpallidum, S. (Ectemnaspis) dinellii, S. (Ectemnaspis) lutzianum, S. (Ectemnaspis) perflavum, S. (Hemicnetha) rubrithorax, S. (Inaequalium) botulibranchium, S. (Inaequalium) clavibranchium, S. (Inaequalium) inaequale, S. (Inaequalium) itaunense, S. (Inaequalium) nogueirai, S. (Inaequalium) subclavibranchium, S. (Inaequalium) subnigrum, S. (Inaequalium) travassosi, S. (Notolepria) paraguayense*, S. (Psaroniocompsa) anamariae*, S. (Psaroniocompsa) angrense, S. (Psaroniocompsa) auripellitum, S. (Psaroniocompsa) auristriatum*, S. (Psaroniocompsa) incrustatum, S. (Psaroniocompsa) jujuyense, S. (Psaroniocompsa) limbatum*, S. (Psaroniocompsa) minuanum*, and S. (Thyrsopelma) orbitale. © 2011 Sociedade Brasileira de Zoologia.

Blood samples from Mansonella ozzardi infected volunteers from Vila Antimary (Amazonas State) were processed and a protocol to isolate and prepare microfilariae was carried out in order to perform Scanning Electron Microscopy (SEM) analysis. Data obtained from ultrastructure showed some undescribed structural points of the parasite such as a dimple in the anterior end of the larva and small points –orifice-like– that may be related to amphidial structures or simply pores. Another interesting feature was the tip of the tail which is very similar to that found in the rodent parasite Dunnifilaria meningica.

The prevalence of ocular lesions due to onchocerciasis was evaluated among residents of the Yanomami Tribe, in the northern Amazon, Brazil, an endemic area for onchocerciasis. 83 natives were submitted to an ocular examination including an external examination, biomicroscopy, intraocular pressure measurement, and a fundus examination. Clinical, parasitological and serological tests were carried out simultaneously. The population demonstrated a high prevalence of eosinophilia, skin microfilaria (55%) and onchocercal subcutaneous nodules (35%). A high prevalence of probable onchocerciasis related eye lesions was detected. Punctate keratitis (41%) and microfilaria in the anterior chamber (39%) were found as well as other probable onchocercotic lesions-chorioretinitis (7.2%) and anterior uveitis (6.0%). Other anterior eye lesions (corneal leucomas, conjunctival injection, lid nodules) occurred in 51% of the individuals. The anterior eye lesions were more prevalent than the posterior lesions. We did not find an association of glaucoma with onchocerciasis. The prevalence of these suggestive ocular lesions strongly correlates with the cutaneous nodules and eosinophilia, suggesting that skin nodules may be an indication for an eye examination. The present study provides evidence that significant infection and eye disease due to onchocerciasis persists in certain regions of Northern South America.

Mansonella ozzardi is a filarial autochthonous parasite of the American continent that is frequently found infecting human beings in the Brazilian Amazon. The human infection by M. ozzardi is still seen as non pathogenic despite the variety of symptoms related to it such as fever, articular pain, headache, lymphadenopathy, eosinophily and pruritic skins eruptions. During an expedition in the Acre State, we were able to visit the Kamikuã, an Indian village located along the Purus river, close to the city of Boca do Acre (Amazonas State). The inhabitants had been diagnosed as harboring dog´s worms (Dirofilaria immitis) but our blood samples collections from some individuals evidenced M. ozzardi infections. In fact, human populations from endemic areas are always complaining about symptoms of M. ozzardi infection and remain living together with high parasitic loads in the expectation of correct diagnostic and treatment. Studies on mansonellosis chemotherapy and control should be carried out in order to add knowledge about the infection and to provide hope and answers for those who live in endemic areas.

An unindentified microfilaria sharing characteristics with Mansonella ozzardi and Onchocerca volvulus was detected in blood samples from seven human volunteers, inhabitants of a community in the border of Amazonas and Acre State. They were detected during epidemiological studies carried out in some communities along Antimary, Acre, and Purus Rivers in the Brazilian Amazon. The most striking difference was presented in the shape of the cephalic space from this microfilaria which was different from those of M. ozzardi and with similarities to O. volvulus in this region, but no remarkable differences were observed at the caudal region. More accurate studies are being carried out in order to provide additional data and supporting evidences before establishment of a new species can be done.

The species of the subgenus Inaequalium are reviewed based on adult and pupal morphology. All main taxonomic characters are fully illustrated together with a key to pupae for species identification. Discussions on the species’ taxonomy and brief summaries of their distribution and biology are also provided. As a result of this study, 14 species are now included in the subgenus Inaequalium. They are placed into two species groups, the botulibranchium species group with three species and the inaequale species group with 11 species, including two that are treated as species inquirendae: S. lurybayae Smart and S. parimaense Ramirez-Perez, Yarzabal, Takaoka, Tada & Ramirez. Simulium lurybayae Smart, S. margaritatum Pepinelli, Hamada & Luz and S. maranguapense (Pessoa, Rios-Velasquez & Py-Daniel) are now placed in the inaequale species group. Two lectotypes are designated for the following species: S. clavibranchium Lutz and S. diversibranchium Lutz. Simulium hauseri (Coscaron & Coscaron-Arias) is regarded as an unavailable name.

In this paper, the first phylogenetic hypothesis for the 13 Southern Hemisphere genera of Simuliidae is proposed, through a cladistic approach. In order to investigate the position of those genera representatives of five Northern Hemisphere genera were also included in the analyses as outgroups. The study was based on a data matrix with 33 terminal taxa and 119 morphological characters of adult, pupa and larva. The phylogenetic analysis under equal weights resulted in four most parsimonious trees, with similar topologies and 349 steps (CI = 49; RI = 68). The analyses showed that all Southern Hemisphere genera of Simuliidae are closer to Simuliini than to Prosimuliini. According to our analyses, Araucnephia Wygodzinsky & Coscarón and Paracnephia Rubtsov are polyphyletic, and Gigantodax Enderlein and Crozetia Davies are monophyletic. It is possible also to recognize the following groups (A. iberaensis Coscarón & Coscarón-Arias + Lutzsimulium s.l. d’Andretta & d’Andretta); ((Simulium Latreille + Metacnephia Crosskey) (Cnesiamima Wygodzinsky & Coscarón (Paraustrosimulium Wygodzinsky & Coscarón + Austrosimulium Tonnoir))); and ((Paracnephia of Australia + Cnesia Enderlein) (Pedrowygomyia Coscarón & Miranda-Esquivel + Gigantodax Enderlein)).

In this paper we clarify the status of some poorly known black fly species from the Neotropical region. Information is provided about their depositories, their condition and on previously established synonyms. Nineteen new synonyms and three new type designations are made based on an examination of type material. The following new synonyms (in brackets) are proposed: S. subpallidum Lutz (= S. acarayense as S. acarayensis Coscaron & Wygodzinsky); S. spinibranchium Lutz (= S. laneportoi Vargas, S. striginotum Enderlein); S. rubrithorax Lutz (= S. mutucuna Nunes de Mello & Vieira da Silva); S. inaequale (Paterson & Shannon) (= Trichodagmia manicata Enderlein, S. clarki Fairchild, S. pseudoexiguum Nunes de Mello & Almeida); S. subnigrum Lutz (= S. subclavibranchium Lutz, S. nahimi Py-Daniel, S.

Detection of Onchocerca volvulus in Simulium populations is of primary importance in the assessment of the effectiveness of onchocerciasis control programs. In Brazil, the main focus of onchocerciasis is in the Amazon region, in a Yanomami reserve. The main onchocerciasis control strategy in Brazil is the semi-annually mass distribution of the microfilaricide ivermectin. In accordance with the control strategy for the disease, polymerase chain reaction (PCR) was applied in pools of simuliids from the area to detect the helminth infection in the vectors, as recommended by the Onchocerciasis Elimination Program for the Americas and the World Health Organization. Systematic sampling was performed monthly from September 1998 to October 1999, and a total of 4942 blackflies were collected from two sites (2576 from Balawaú and 2366 from Toototobi). The molecular methodology was found to be highly sensitive and specific for the detection of infected and/or infective blackflies in pools of 50 blackflies. The results from the material collected under field conditions showed that after the sixth cycle of distribution of ivermectin, the prevalence of infected blackflies with O. volvulus had decreased from 8.6 to 0.3% in Balawaú and from 4 to 0.1% in Toototobi.

The homogeneity of the Simuliidae family has produced several taxonomic problems along the years. The studies of Brazilian Simulium Latreille, 1802 date from the beginning of the 20th century, with species described by Kollar, Macquart, Goeldi and Lutz. Lutz's scientific collection is a historical relic of scientific relevance, since it congregates types described from Brazil. Besides its taxonomic importance, this collection can now be used as a bio indicator. However, a lot of these slide-mounted specimens could not support the effects of time, constant handling, fungus and climatic conditions that occurred over the years. The development of a slide-mounted restoration technique had therefore become necessary for specimen preservation and observation.A homogeneidade da família Simuliidae tem resultado problemas taxonômicos ao longo dos anos. Os estudos sobre Simulium Latreille, 1802 no Brasil datam do início do século XX, com espécies descritas por Kollar, Macquart, Goeldi e Lutz. A coleção de Lutz possui relevância científica e histórica, possuindo exemplares tipo descritos do Brasil. Além da importância taxonômica, a coleção de simulídeos de Lutz pode ser usada como bioindicadora. No entanto, muitas lâminas não suportaram os efeitos do tempo, constante manuseio, presença de fungos e ação das condições climáticas ao longo dos anos. O desenvolvimento de uma técnica de restauração do material preservado em lâminas fez-se necessário para melhor preservação e observação do material.

Neste trabalho é apresentada uma chave dicotômica de identificação de pupas de Simuliidae com registro de ocorrência para o Sudeste do Brasil. Nós incluímos as 49 espécies que apresentam a pupa descrita. Na chave, além de caracteres comumente usados (e.g. número dos filamentos branquiais, forma do ápice e forma do casulo), foram usados caracteres não usuais (largura e comprimento relativos dos filamentos branquiais; disposição espacial das brânquias; proporção entre comprimento da brânquia e comprimento do casulo; presença e posição do assoalho do casulo). É possível diferenciar 70% das espécies de Simuliidae do Sudeste do Brasil usando apenas caracteres da pupa. Este estágio, muitas vezes, é o único do qual se obtém uma identificação precisa. In this work is given a dichotomic identification key to pupae of Simuliidae recorded from Southeastern Region of Brazil. We included the 49 species which already have their pupae described. In the key, besides characters commonly used (e.g. number of gill filaments, shape of apex and shape of cocoon), we used unusual characters (relative width and length of gill filaments; spacial configuration of gills; proportion of gill length to cocoon length; presence and position of cocoon floor). It is possible to recognize 70% of Simuliidae species from Southeastern Region of Brazil only using pupae characters. Often, this is the unique stage which one can access a precise identification of the species.

Neste trabalho é apresentada uma chave dicotômica de identificação de pupas de Simuliidae com registro de ocorrência para o Sudeste do Brasil. Nós incluímos as 49 espécies que apresentam a pupa descrita. Na chave, além de caracteres comumente usados (e.g. número dos filamentos branquiais, forma do ápice e forma do casulo), foram usados caracteres não usuais (largura e comprimento relativos dos filamentos branquiais; disposição espacial das brânquias; proporção entre comprimento da brânquia e comprimento do casulo; presença e posição do assoalho do casulo). É possível diferenciar 70% das espécies de Simuliidae do Sudeste do Brasil usando apenas caracteres da pupa. Este estágio, muitas vezes, é o único do qual se obtém uma identificação precisa.In this work is given a dichotomic identification key to pupae of Simuliidae recorded from Southeastern Region of Brazil. We included the 49 species which already have their pupae described. In the key, besides characters commonly used (e.g. number of gill filaments, shape of apex and shape of cocoon), we used unusual characters (relative width and length of gill filaments; spacial configuration of gills; proportion of gill length to cocoon length; presence and position of cocoon floor). It is possible to recognize 70% of Simuliidae species from Southeastern Region of Brazil only using pupae characters. Often, this is the unique stage which one can access a precise identification of the species.

During studies on the taxonomy of the Simuliidae of Brazil, a new species of Simulium was found. Full descriptions of the adults and pupae of this species are described here, its affinities with other species are discussed and its distribution, biology, and medical importance in Brazil are recorded.

O presente trabalho é parte de uma dissertação de mestrado em elaboração no curso de pós-graduação em biologia animal da Universidade Federal do Rio de Janeiro (UFRJ), apoiado pela CAPES. Nele, são apresentadas as espécies de simuliídeos que pertencem à coleção de Adolpho Lutz depositadas no Laboratório de Simuliídeos e Oncocercose do Departamento de Entomologia do Instituto Oswaldo Cruz (IOC). Pioneiro no estudo desses dípteros, Lutz descreveu cerca de 25 espécies de diferentes localidades do Brasil. Vetor da oncocercose, os simuliídeos tiveram sua importância médico-sanitária reconhecida em fins da década de 1920.This paper is part of a master's thesis currently being written under the auspices of the Post-Graduate Program in Animal Biology of the Federal University of Rio de Janeiro, with support from CAPES. It presents the species of black flies in Adolpho Lutz's collection, held at the Laboratory of Black Flies and Oncocercosis of the Department of Entomology of the Instituto Oswaldo Cruz. A pioneer in the study of these dipterons, Lutz described about 25 species from different places in Brazil. A vector of round worm, the black fly's importance to public health was recognized at the end of the 1920s.

A oncocercose é causada por um verme parasita, a Onchocerca, e transmitida pelo mosquito borrachudo, simuliídeo, podendo causar cegueira em seu estado agudo. Oriunda do continente africano onde é disseminada, foi descoberta na América Latina, na Guatemala, em 1917, com registros posteriores no México, Venezuela, Colômbia e Brasil. O estabelecimento da doença nas Américas tem intrigado os especialistas, e ainda hoje é uma questão em aberto. O projeto multidisciplinar descrito nesta nota de pesquisa objetiva investigar os aspectos históricos da introdução e disseminação da doença na América Latina, e realizar estudos comparativos sobre a história da doença nos dois continentes. A importância que adquiriu acarretou a revalorização das coleções de simuliídeos, cujas espécies brasileiras começaram a ser estudadas por Adolpho Lutz no início do século XX.Round worm is a parasite, Onchocerca, and is transmitted by a black fly, simuliídeo; it can cause blindness. Originally from the African continent, where it is widespread, in Latin America it was first discovered in Guatemala in 1917; later instances were recorded in Mexico, Venezuela, Colombia and Brazil. The establishment of this disease in the Americas has intrigued scientists since then and today it is an open question. The multidisciplinary project described in this research note aims to investigate historical aspects of the arrival and spread of the disease in Latin America and, to make comparative studies of the history of the disease on both continents. The increasing importance of the disease has meant greater value being attributed to collections of simuliídeo, whose Brazilian species were first studied by Adolpho Lutz at the beginning of the 20th century.

O presente trabalho é parte de uma dissertação de mestrado em elaboração no curso de pós-graduação em biologia animal da Universidade Federal do Rio de Janeiro (UFRJ), apoiado pela CAPES. Nele, são apresentadas as espécies de simuliídeos que pertencem à coleção de Adolpho Lutz depositadas no Laboratório de Simuliídeos e Oncocercose do Departamento de Entomologia do Instituto Oswaldo Cruz (IOC). Pioneiro no estudo desses dípteros, Lutz descreveu cerca de 25 espécies de diferentes localidades do Brasil. Vetor da oncocercose, os simuliídeos tiveram sua importância médico-sanitária reconhecida em fins da década de 1920. This paper is part of a master's thesis currently being written under the auspices of the Post-Graduate Program in Animal Biology of the Federal University of Rio de Janeiro, with support from CAPES. It presents the species of black flies in Adolpho Lutz's collection, held at the Laboratory of Black Flies and Oncocercosis of the Department of Entomology of the Instituto Oswaldo Cruz. A pioneer in the study of these dipterons, Lutz described about 25 species from different places in Brazil. A vector of round worm, the black fly's importance to public health was recognized at the end of the 1920s.

A oncocercose é causada por um verme parasita, a Onchocerca, e transmitida pelo mosquito borrachudo, simuliídeo, podendo causar cegueira em seu estado agudo. Oriunda do continente africano onde é disseminada, foi descoberta na América Latina, na Guatemala, em 1917, com registros posteriores no México, Venezuela, Colômbia e Brasil. O estabelecimento da doença nas Américas tem intrigado os especialistas, e ainda hoje é uma questão em aberto. O projeto multidisciplinar descrito nesta nota de pesquisa objetiva investigar os aspectos históricos da introdução e disseminação da doença na América Latina, e realizar estudos comparativos sobre a história da doença nos dois continentes. A importância que adquiriu acarretou a revalorização das coleções de simuliídeos, cujas espécies brasileiras começaram a ser estudadas por Adolpho Lutz no início do século XX. Round worm is a parasite, Onchocerca, and is transmitted by a black fly, simuliídeo; it can cause blindness. Originally from the African continent, where it is widespread, in Latin America it was first discovered in Guatemala in 1917; later instances were recorded in Mexico, Venezuela, Colombia and Brazil. The establishment of this disease in the Americas has intrigued scientists since then and today it is an open question. The multidisciplinary project described in this research note aims to investigate historical aspects of the arrival and spread of the disease in Latin America and, to make comparative studies of the history of the disease on both continents. The increasing importance of the disease has meant greater value being attributed to collections of simuliídeo, whose Brazilian species were first studied by Adolpho Lutz at the beginning of the 20th century.

The effectiveness of the MosqTent® trap was evaluated in endemic area to onchocerciasis in Brazil. This study seeks to provide subsidies for the monitoring of the onchocerciasis transmission in the country. The study was carried out at the Homoxi and Thirei villages, located in the Yanomami Indigenous Land, in the state of Roraima. This area presents hyperendemicity, high blackflies densities, large population migrations and mining activities. The Homoxi and Thirei villages are assisted by the Brazilian Ministry of Health. To conduct the present study, the village leader, health leaders and the Brazilian Ethics Committee were consulted. Blackflies captures were carried out simultaneously at the Homoxi and Thirei, using systematized methods to allow for comparisons between the traditional Human Landing Catch (HLC) and HLC protected by the MosqTent®. The female blackflies were captured at two equidistant capture stations per locality, by two collectors per station, for five consecutive days. Individuals captured by interval/station/day were counted, identified and maintained at -20°C. The underlying probability distributions and the differences between the methods for the independent sample data were verified in a comparative statistical analysis between the use of the MosqTent® and the HLC. A total of 10,855 antropophilic blackflies were captured by both methodologies. A total of 7,367 (67.87%) blackflies belonging to seven species were captured by MosqTent® -Simulium incrustatum s.l (99.06%); S. guianense s.l (0.74%), S. oyapockense s.l (0.01%), S. exiguum (0.10%), S. metallicum (0.05%), S. ochraceum (0.03%) and S. minusculum s.l (0.01%). Moreover, 3,488 (32.14%) blackflies belonging to four species were captured by HLC-S. incrustatum s.l (98.33%); S. guianense s.l (1.38%), S. oyapockense s.l (0.26%) and S. metallicum (0.03%). The MosqTent® was more effective and efficient when compared to HLC. When comparing total blackflies captured/day, the MosqTent® was more efficient than HLC (p = 0.031) with a means of 799.4 blackflies/day versus 217.6 blackflies/day by HLC. The results demonstrated improved performance and high reliability of the MosqTent® compared to the traditional HLC method.

Monthly collections were made of man-biting female blackflies: Simulium auripellitum Enderlein, S. guianense Wise, S. minusculum Lutz and S. nigrimanum Macquart (Diptera: Simuliidae) from four catching stations in the newly discovered focus of human onchocerciasis at Minacu (13 degrees 35 minutes S 48 degrees 18 minutes W), 300 km north of Brasilia in Goias State. These provided baseline data on biting habits, population density and seasonal prevalence during the year before completion of the Serra da Mesa hydroelectric dam on the Rio Tocantins near Minacu, in a project investigating the effect of dam construction on onchocerciasis transmission in the area. All four simuliid species were most abundant during the dry season, and only bit in low numbers (S. auripellitum S. minusculum, S. nigrimanum) or were absent (S. guianense) in the wet season. Simulium minusculum was the predominant species at all catching stations, being particularly abundant by the large River Tocantins. The other three species were mainly associated with smaller rivers. In the dry season, biting rhythms of S. minusculum varied with catching site, while S. nigrimanum showed peaks of activity in early morning and during the afternoon. Experimental infection with Onchocerca volvulus (Leuckart) (Nematoda: Onchocercidae), from a human volunteer, showed that this parasite could develop fully in the four simuliid species, which are all considered to be potential vectors in the area.

The internal transcribed spacer region (ITS1, 5.8S gene and ITS2) of the two filarial nematodes Onchocerca volvulus and Mansonella ozzardi was sequenced, and two species-specific primers designed in the ITS2 to develop a PCR-based method for their specific detection and differentiation. When used with a universal reverse primer, the two species-specific primers gave amplification products of different size, which were readily separated in an agarose gel. The PCR was tested on skin biopsies from 51 people from three localities in Brazil where M. ozzardi is present, and results have been compared with those of parasitological examination of blood. The species-specific PCR gave a higher percentage of detection of infection by M. ozzardi than the parasitological examination of blood. No infection with O. volvulus was detected by PCR. This PCR-based assay may assist in determining the nature of infection in areas where both filarial species exist in sympatry.

An autochthonous case of human onchocerciasis was reported 13 years ago in the town of Minaçu, northern Goiás (Brazil), but a subsequent survey of the population using the traditional technique of examining skin biopsies with the light microscope failed to detect other cases. Recent surveys using more sensitive diagnostic techniques (serodiagnosis, DNA probes, Mazzotti test) that are detailed in this paper revealed the presence of other cases of the disease in Minaçu, the nearby town of Formoso and at the Buracão gold mine near Paranã. The data show that transmission of the disease has occurred to local people living in town and on farms and that gold miners (garimpeiros) are a likely source of infection.

This study aimed to evaluate the influence of water velocity speed on the local distribution and taxocenosis structure of blackfly larvae. The larvae were collected from two adjacent streams located in the municipality of Angra dos Reis (RJ): Caputera River and one of its tributaries. Riffle litter patches were sampled randomly using a 30 x 30 cm quadrat. Four blackfly species were found: Simulium incrustatum s. l. Lutz, 1910; Simulium (Inaequalium) sp. ; Simulium pertinax s. l. Kollar, 1832 and Simulium subpallidum s. l. Lutz, 1909. Among these species, Simulium pertinax s. l. was clearly associated with higher water current speeds, while Simulium subpallidum s. l. showed association with lower water velocities, and Simulium (Inaequalium) sp. had a relatively constant distribution along the water current gradient.Este estudo teve como objetivo avaliar, nos criadouros de simulídeos, a influência da velocidade da água sobre a ocorrência de suas larvas e estrutura de suas taxocenoses. Para obtenção da amostragem foram utilizados "quadrats" de madeira distribuídos aleatoriamente no rio Caputera e um de seus tributários. Foram encontradas quatro espécies: Simulium incrustatum sl. Lutz, 1910; Simulium (Inaequalium) sp. ; Simulium pertinax sl. Kollar, 1832 e Simulium subpallidum sl. Lutz 1909. S. (Inaequalium) sp. teve uma distribuição quase constante ao longo do gradiente de correnteza. S. pertinax se mostrou fortemente associada às velocidades mais altas de correnteza, enquanto que S. subpallidum se mostrou associado às velocidades mais baixas.

This study aimed to evaluate the influence of water velocity speed on the local distribution and taxocenosis structure of blackfly larvae. The larvae were collected from two adjacent streams located in the municipality of Angra dos Reis (RJ): Caputera River and one of its tributaries. Riffle litter patches were sampled randomly using a 30 x 30 cm quadrat. Four blackfly species were found: Simulium incrustatum s. l. Lutz, 1910; Simulium (Inaequalium) sp. ; Simulium pertinax s. l. Kollar, 1832 and Simulium subpallidum s. l. Lutz, 1909. Among these species, Simulium pertinax s. l. was clearly associated with higher water current speeds, while Simulium subpallidum s. l. showed association with lower water velocities, and Simulium (Inaequalium) sp. had a relatively constant distribution along the water current gradient.

Onchocerca cervicalis Railliet & Henry, 1910 is a nematode that parasite equines. Its ocurrence has already been reported in the States of Mato Grosso and Rio de Janeiro, Brazil. Different diagnostic techniques were used in this study to establish the prevalence of the parasite in Rio de Janeiro State and the biting behaviour of the simuliid and ceratopogonid species suspected of being vectors was studied. All of the biopsies made in the region of the withers, shoulder and umbilicus of 57 animals were negative. Necropsies carried out on 28 equines revealed 4 to be positive for the parasite; 2 for microfilariae and 2 for adults. Simuliid flies showed preference for biting the ventral region and ceratopogonids the lower parts of the legs of horses. It was concluded that a more detailed investigation is required to determine a better diagnostic technique in order to verify prevalence rates of the parasite in horses in the State.

Foram encontradas seis novas ocorrências de Simuliidae para o estado do Rio de Janeiro: Simulium (Chirostilbia) empascae, S. (C.) subpallidum, S. (Hemicetha) brachycladum, S. (Inaequalium) inaequale, S. (Psaroniocompsa) auripellitum e S. (Trichodagmia) nigrimanum.

We describe the abiotic factors affecting the distribution of black flies at a microhabitat scale, rather than at the regional scale usually present in the literature on the Neotropics. Black fly larvae were sampled from the Tocantins River and three tributaries, located in the Brazilian savanna (state of Tocantins, Brazil) during six bi-monthly sampling periods from October 2004-August 2005. At each sampling site, 15 random quadrats (30 x 30 cm) were sampled each period and for each quadrat were determined mean water velocity, predominant substrate type (rocks, riffle litter or riparian vegetation) and depth detrended correspondence analysis (DCA) was used to determine associations with current velocity, whereas correspondence analysis (CA) was used to estimate site specific current velocity associations. Canonical correspondence analysis (CCA) was used to identify general microhabitat associations. The CCA showed that most species had a trend towards riffle litter, except for Simulium nigrimanum associated with rocky substrate and Simulium cuasiexiguum associated with riparian vegetation. The DCA showed a well defined pattern of water velocity associations. The CA revealed that the species showed different speed associations from one site to another, suggesting different competitive pressures resulting in the occurrence of different realized niches.

Our goal was to verify the presence and the composition of black floy species in the Antimari and Acre rivers, located in the end of Western Amazonia, where this entomological inquiry was accomplished. Along the Antimari and Acre rivers, 19 localities were studied and 133 larvae and 197 pupae were collected, totalizing 330 black floy immatures. The following species are recorded for the first time in this area: Simulium (Psaroniocompsa) amazonicum Goeldi, Simulium (Psaroniocompsa) oyapockense Floch & Abonnenc, Simulium (Psaroniocompsa) quadrifidum Lutz, Simulium (Psilopelmia) lutzianum Pinto, Simulium (Psilopelmia) perfloavum Roubaud and Simulium (Notolepria) exiguum Roubaud. Our data suggest that S. amazonicum, S. oyapockense and S. quadrifidum have a wide geographical distribution as well as population density.

In the current study, it was assessed, for the first time, the effect of ivermectin treatment administered twice a year on the prevalence and morbidity of onchocerciasis in the hyperendemic Yanomami communities of the Roraima State (Brazil). Physical and parasitological examinations were carried out every 6 months until six drug rounds of treatment were completed. The coverage during the six rounds of ivermectin treatment ranged from 89% to 92% of the eligible Yanomami population. Overall, comparison of results at pre-treatment with results after six rounds of treatment, the prevalence of infection had declined from 87% to 42% (P0.0001, CI 95%=0.05-0.22); the community microfilarial load (CMFL) fell from 1.17 to 0.53Mf/mg of skin; and the crude intensity of infection (MFL-Total) decreased from 18.95 to 1.96Mf/mg of skin during the same period (P0.0001, for both microfilarial loads). Although no significant difference was observed between microfilarial densities in skin snips from iliac crest and scapula after the 6th round of ivermectin treatment it was observed that the prevalence of positive skin snips was significantly higher when skin snips were taken from iliac crest (42%) than from scapula (8%) (P=0.001, CI 95%=3.41-22.67). After six rounds of ivermectin treatments, no significant differences were observed in the prevalences of palpable nodules and of onchodermatitis in relation to pre-treatment prevalences, from 45% to 41% and from 17% to 20% (P0.05, for both). These findings suggest that mass population treatment should continue without interruption and achieve higher levels of drug coverage in order to alleviate disease manifestations and interrupt infection transmission to hasten the elimination of onchocerciasis in Yanomami communities. In addition, the sensitivity of iliac crest snips for parasitological assessment in epidemiological surveillance of Yanomami communities may increase the acceptance of the population in biopsy sampling and seems to be a good choice for assessing the success of control programs.

Detection of Onchocerca volvulus in Simulium populations is of primary importance in the assessment of the effectiveness of onchocerciasis control programs. In Brazil, the main focus of onchocerciasis is in the Amazon region, in a Yanomami reserve. The main onchocerciasis control strategy in Brazil is the semi-annually mass distribution of the microfilaricide ivermectin. In accordance with the control strategy for the disease, polymerase chain reaction (PCR) was applied in pools of simuliids from the area to detect the helminth infection in the vectors, as recommended by the Onchocerciasis Elimination Program for the Americas and the World Health Organization. Systematic sampling was performed monthly from September 1998 to October 1999, and a total of 4942 blackflies were collected from two sites (2576 from Balawau and 2366 from Toototobi). The molecular methodology was found to be highly sensitive and specific for the detection of infected and/or infective blackflies in pools of 50 blackflies. The results from the material collected under field conditions showed that after the sixth cycle of distribution of ivermectin, the prevalence of infected blackflies with O. volvulus had decreased from 8.6 to 0.3% in Balawau and from 4 to 0.1% in Toototobi.

The homogeneity of the Simuliidae family has produced several taxonomic problems along the years. The studies of Brazilian Simulium Latreille, 1802 date from the beginning of the 20th century, with species described by Kollar, Macquart, Goeldi and Lutz. Lutz's scientific collection is a historical relic of scientific relevance, since it congregates types described from Brazil. Besides its taxonomic importance, this collection can now be used as a bio indicator. However, a lot of these slide-mounted specimens could not support the effects of time, constant handling, fungus and climatic conditions that occurred over the years. The development of a slide-mounted restoration technique had therefore become necessary for specimen preservation and observation. A homogeneidade da família Simuliidae tem resultado problemas taxonômicos ao longo dos anos. Os estudos sobre Simulium Latreille, 1802 no Brasil datam do início do século XX, com espécies descritas por Kollar, Macquart, Goeldi e Lutz. A coleção de Lutz possui relevância científica e histórica, possuindo exemplares tipo descritos do Brasil. Além da importância taxonômica, a coleção de simulídeos de Lutz pode ser usada como bioindicadora. No entanto, muitas lâminas não suportaram os efeitos do tempo, constante manuseio, presença de fungos e ação das condições climáticas ao longo dos anos. O desenvolvimento de uma técnica de restauração do material preservado em lâminas fez-se necessário para melhor preservação e observação do material.

Este estudo teve por objetivo verificar padrões morfológicos que proporcionassem o correto diagnóstico de Simulium (Chirostilbia) pertinax Kollar. A análise morfológica de fêmeas e pupas permitiu encontrar estruturas bem características e de fácil utilização para identificação da espécie. Alguns caracteres diagnósticos (coloração do escudo, área nudiocular e paraprocto) podem apresentar pequenas variações e outros são constantes (coloração das pernas, cibário, forquilha, filamentos branquiais e casulo). This study had as objective to verify the morphologic patterns that provide a correct diagnosis of Simulium (Chirostilbia) pertinax Kollar. The analysis of female and pupa morphology allowed to find characteristic structures that could be easily used to identify the species.Some diagnostic characteres (shield coloration, nudiocular area and paraprocto) show small variations and other are constant (leg coloration, cibarium, fork, branchial filaments and cocoon).

Round worm is a parasite, Onchocera, and is transmitted by a black fly, simulidae; it can cause blindness. Originally from the African continent, where it is widespread, in Latin America it was first discovered in Guatemala in 1917; later instances were recorded in Mexico, Venezuela, Colombia and Brazil. The establishment of this disease in the Americas has intrigued scientists since then and today it is an open question. The multidisciplinary project described in this research note aims to investigate historical aspects of the arrival and spread of the disease in Latin America and, to make comparative studies of the history of the disease on both continents. The increasing importance of the disease has meant greater value being attributed to collections of simuliídeo, whose Brazilian species were first studied by Adolpho Lutz at the beginning of the 20th century.

There is no published account which allows the morphological discrimination of microfilariae of Onchocerca volvulus and M. ozzardi from each other. However, they occur together in parts of Brazil and Venezuela, and presumably there is always the possibility that migration could establish new sympatric populations in the future. The objective of this study was to evaluate simple morphological characters that might be used for species-diagnosis of microfilariae. The conclusions were that the location of microfilariae in the blood or skin, the body size and the nucleation of the nerve ring are expected to be useful first indications of species identity, but cannot be used for confident diagnosis. The structure of the cephalic armature (stained with alcian blue) seems to be species specific, but is of limited application because it is often difficult to see. However, the pattern of nucleation of the tail (as expressed by the ratio of the length of the terminal nucleus compared with the length of the tail space) is distinctive and is expected to be diagnostic.