Larvicidal activity of plants from Myrtaceae against Aedes aegypti L. and Simulium pertinax Kollar (Diptera)

Abstract INTRODUCTION: Despite their widespread usage, synthetic insecticides and larvicides are harmful for controlling disease-causing mosquitoes owing to the development of resistance. The leaves of Eugenia astringens, Myrrhinium atropurpureum, and Neomitranthes obscura were collected from Marambaia and Grumari restingas. The safety and larvicidal efficacy of their extracts were tested against Aedes (Stegomyia) aegypti L. and Simulium (Chirostilbia) pertinax Kollar. METHODS: The dry leaves were subjected to static maceration extraction using 90% methanol. A. aegypti and S. pertinax larvae were exposed to 7.5, 12.5, and 25.0 µL/mL of the extracts (n= 30). The larvicidal activity after 24 h and 48 h, and the mortality, were determined. The median lethal concentration (CL50) was estimated by a Finney's probit model. RESULTS: M. atropurpureum and E. astringens extracts exhibited the strongest larvicidal effects against A. aegypti. M. atropurpureum extracts (25 µL/mL) caused mortalities of over 50% and 100% after 24 h and 48 h, respectively (CL50 = 11.10 and 9.68 ppm, respectively). E. astringens extracts (25 µL/mL) caused mortalities of 50% and 63.33% after 24 h and 48 h, respectively. High concentrations of N. obscura extracts induced a maximum mortality of 46.66% in A. aegypti larvae after 48 h (CL50= 25 ppm). The larvae of S. pertinax showed 100% mortality following exposure to all the plant extracts at all the tested concentrations after 24 h. CONCLUSIONS: The extracts of M. atropurpuerum exhibited the strongest larvicidal activity against A. aegypti. The larvae of S. pertinax were sensitive to all the extracts at all the tested concentrations.

Infectivity of Simulium damnosum s.l. and therapeutic coverage of ivermectin distribution 10 years post treatment around Owena Dam, Ondo state, Nigeria

ABSTRACT Background: Studies related to infectivity status of insect vectors are seen as necessities in understanding the epidemiology of vector-borne diseases and planning effective control measures. This study assessed the infectivity ofSimulium damnosum s.l. around Owena River as well as evaluated therapeutic coverage of Ivermectin distribution in the area. Method: Human landing sampling method was used to collect adult flies on human attractants from 07:00 to 18:00 for two consecutive days a month for three months (July 2016 - September 2016). Parity assessment was conducted to determine the age of fly populations. Parous flies were further dissected to detect the presence or absence ofOnchocerca larvae. Biting rates and transmission potentials were calculated using standard methods. A quantitative survey was carried out to determine the therapeutic coverage and compliance to ivermectin treatment for the control of Onchocerciasis in the study area using standard household coverage questionnaires. Results: A total of 914 adult female flies were collected during the study period. The daily biting rate (DBR) varied from 146 fly per man day (FMD) in July to 162.5 FMD in August. The monthly biting rate (MBR) was lowest in September (2170 bites per man per month) but highest in August (3358.3 bites per man per month). MBD ranged from 13.23 fly per man hour (FMH) in July to 14.77 FMH in August. The results indicated that the majority of the flies collected at the sampling points were nulliparous [685 (74.95%)] while others were parous [229 (25.05%)]. The biting activity of the flies showed a marked decrease in population in August compared to July which later increased in September. Infection rates varied from 2 (0.7%) in July to 7 (2.2%) in August while the infectivity rate during the study ranged from zero (July and September) to 3 (1.0%) in August. Conclusion: Despite the years of treatment of onchocerciasis in Owena community, there were still some infective flies capable of transmitting O. volvolus. This could be due to the low rate of therapeutic coverage as a result of non-compliance in the community for various reasons earlier stated.

Abundance and diversity of black flies (Diptera: Simuliidae) in rivers of the Andean Eastern Hills of Bogotá (Colombia), and its relationship with water stream physicochemical variables / Abundancia y diversidad de moscas negras (Díptera: Simuliidae) en ríos de los Cerros Orientales Andinos de Bogotá (Colombia), y su relación con variables fisicoquímicas de las corrientes de agua / Abundancia e diversidade de moscas negras (Diptera: Simuliidae) em rios dos Cerros Orientais Andinos de Bogotá (Colômbia), e sua relação com variáveis físico-químicas das correntes de água

Abstract Black flies are abundant benthic organisms in well-oxygenated running water and are considered effective bioindicators of water quality. Information on the ecology of these organisms at the species level is important, since up to now information has mainly been available on a family level. The aim of this study was to evaluate the composition of black flies and their relationships to a group of physical and chemical factors in four small rivers of the Eastern Hills around Bogotá, Colombia. These headwaters are protected by the Empresa de Acueducto y Alcantarillado de Bogotá. Black fly larvae and pupae were collected during four sampling periods during the dry season to the early rainy season of 2012. Multivariate methods were used to determine the presence of each species in relation to dissolved oxygen, nitrates, pH, temperature, and water velocity. PCA ordination revealed a physicochemical environment with a tendency towards a certain homogeneity in the four rivers studied. The DCA ordination confirmed that in La Vieja River the G. ortizi complex dominated while S. muiscorum was dominant in the other three rivers. Similarly, according to the NMDS, the composition of black flies in Arzobispo and Chorro de Padilla rivers was similar, while that of El Delirio and La Vieja rivers were different, especially in this last river. The rivers had low species richness (four species and one species complex). Simulium muiscorum was negatively correlated with dissolved oxygen, temperature and current velocity while S. ignescens was associated with slightly more oxygenated waters and S. furcilatum with faster currents. The low species diversity and richness for the four rivers is consistent with previous reports of low Neotropical diversity of black flies. Results showed that simuliid species could possibly be good indicators of the environmental conditions of Eastern Hills rivers around Bogotá.

Resumen Las moscas negras son organismos bénticos abundantes en corrientes de agua bien oxigenadas y se consideran bioindicadores efectivos de la calidad de agua. La información sobre la ecología de estos organismos a nivel de especie es importante, ya que hasta el momento, ha estado disponible principalmente solo a nivel de familia. El objetivo de este estudio fue evaluar la composición de moscas negras y sus relaciones con un grupo de factores físicos y químicos en cuatro ríos pequeños de los Cerros Orientales alrededor de Bogotá, Colombia. Estos nacimientos están protegidos por la Empresa de Acueducto y Alcantarillado de Bogotá, Colombia. Se colectaron larvas y pupas de moscas negras a lo largo de cuatro períodos de muestreo, desde la estación seca hasta la estación lluviosa de 2012. Se utilizaron métodos multivariados para determinar la presencia de cada especie en relación con: oxígeno disuelto, nitratos, pH, temperatura y velocidad del agua. La ordenación por PCA reveló un ambiente fisicoquímico con tendencia hacia la homogeneidad en los cuatro ríos estudiados. La ordenación por DCA confirmó que en el río La Vieja dominó el complejo G. orti%i, mientras que S. muiscorum fue dominante en los otros tres. De igual forma de acuerdo con el análisis NMDS, la composición de moscas negras en los ríos Arzobispo y Chorro de Padilla fue similar, mientras que en los ríos El Delirio y La Vieja fue diferente, especialmente en este último. Los ríos presentaron baja riqueza de especies (cuatro especies y un complejo de especies). Simulium muiscorum se correlacionó negativamente con el oxígeno disuelto, temperatura y velocidad de la corriente, mientras que S. ignescens estuvo asociado con aguas ligeramente más oxigendas y S. furcilatum, con corrientes más rápidas. La baja diversidad y riqueza para los cuatro ríos es consistente con reportes previos de baja diversidad neotropical de moscas negras. Los resultados muestran que las especies de simúlidos podrían ser buenos indicadores de las condiciones ambientales de los ríos de los Cerros Orientales de Bogotá.

Resumo As moscas negras são organismos bentônicos abundantes em correntes de água bem oxigenadas e se consideram bioindicadores efetivos da calidade de água. A informação sobre a ecologia de estes organismos quanto a espécie é importante, pois até o momento, há informação somente em nível de família. O objetivo de este estudo foi avaliar a composição de moscas negras e suas relações com um grupo de fatores físicos e químicos em quatro rios pequenos dos Cerros Orientais nas redondezas de Bogotá, Colômbia. As nascentes estão protegidas pela Empresa de Acueducto y Alcantarillado de Bogotá, Colômbia. Foram coletadas larvas e poupas de moscas negras ao longo de quatro períodos de amostragem, desde a estação seca até a estação chuvosa de 2012. Foram utilizados métodos multivariados para determinar a presença de cada espécie em relação com: oxigênio dissolvido, nitratos, pH, temperatura e velocidade da água. A ordenação por PCA revelou um ambiente físico-químico com tendência à homogeneidade nos quatro rios estudados. A ordenação por DCS confirmou que no rio La Vieja dominou o complexo G. orti%i, enquanto que S. muiscorum foi dominante nos outros três rios. Igualmente, de acordo com a análise NMDS, a composição de moscas negras nos rios Arzobispo e Chorro de Padilla foi similar, enquanto que nos rios El delírio e La Vieja foi diferente, em especial neste último. Os rios apresentaram baixa riqueza de espécies (quatro espécies e um complexo de espécies). S. muiscorum se correlacionou negativamente com o oxigênio dissolvido, temperatura e velocidades da corrente, enquanto que S. ignescens foi associado com águas ligeiramente mais oxigenadas e S. furcilatum, com correntes mais rápidas. A baixa diversidade e riqueza para os quatro rios é consistente com reportes prévios de baixa diversidade neotropical de moscas negras. Os resultados mostram que espécies de Simulium poderiam ser boas indicadoras das condições ambientais dos rios dos Cerros Orientais de Bogotá.

Genoma mitocondrial de Simulium spp. e Onchocerca volvulus na Amazônia brasileira / Mitochondrial genome of Simulium spp. and Onchocerca volvulus in the Brazilian Amazon

As espécies de simulídeos são vetores de filárias, como as do gênero Onchocerca e Mansonella, que são os agentes etiológicos da oncocercose e mansonellose, respectivamente. Essas duas filárias ocorrem na região Amazônica brasileira e são transmitidas pelas seguintes espécies de vetores: Simulium incrustatum, S. limbatum, S. oyapockense, S. exiguum, S. guianense, e S. roraimense. As espécies de Simulium tem sido designada com base em caracteres morfológicos, os quais, em alguns casos, não são bem discriminativos. Recentemente, o gene mitocondrial Citocromo c-oxidase 1 (CO1) e a região nuclear Internal Transcribed Spacer (ITS) tem sido utilizados para descriminar espécies e definir populações dentro deste gênero. Entretanto, existe um grande gap acerca da informação genética de Simulium, o qual é considerado a linha de base para estudos ecológicos e populacionais. Considerando este cenário, nosso objetivo foi aplicar a metagenômica para recuperar genomas mitocondriais de amostras brasileiras S. incrustatum e S. oyapockense do foco de oncocercose e também a informação genética a respeito de seus microbiomas. O DNA total de dez simulídeos, morfologicamente identificados como S. incrustatum (3) e S. oyapockense (7) foram sequenciados randomicamente na plataforma Illumina HiSeq 2500. Nós recuperamos dez genomas mitocondriais com cobertura média de 15,591 bp e conteúdo médio de GC de 22,94 %, apresentando o mesmo conteúdo gênico e em sintenia. Baseado nestes mitogenomas, no gene mitocondrial CO1, e também na região nuclear (ITS), realizamos análises filogenéticas que mostraram a presença de três espécies conhecidas dentre as amostras: S. incrustatum, S. oyapockense e S. guianense, e também um grupo de amostras pertencentes à Simulium spp. Nós também recuperamos um genoma mitocondrial de Onchocerca volvulus da amostra aqui identificada como S. guianense.

Análises taxonômicas do microbioma dos simulídeos revelaram Proteobacteria e Ascomycota como os filos mais abundantes. A análise funcional revelou que a família de enzimas das Transcriptases Reversas são as mais abundantes. Portanto, nós contribuímos com informação genética original preenchendo parte do viés a respeito das espécies de Simulium associadas ao foco brasileiro de oncocercose. (AU)

Blackfly control from a health education perspective: the individual, the organization, and sustainability of the process

Abstract 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.

Oncocercosis: de lo básico a lo clínico / Onchocerciasis: From basics to clinical / Oncocercose: do básico ao clínico

La oncocercosis es una de las enfermedades tropicales desatendidas, producida por el nemátodo filárico Onchocerca volvulus y transmitida por la picadura de la mosca negra del género Simulium. Es considerada la segunda causa mundial de ceguera prevenible y está presente en 35 naciones de tres continentes: África, América y Asia. Existen tres países declarados libres de oncocercosis: Colombia, Ecuador y México. Las principales manifestaciones clínicas son dermatológicas y oculares; sin embargo, también se han descrito alteraciones linfáticas y neurológicas. El diagnóstico se realiza por identificación de microfilarias en biopsia de piel o esclerocorneal, nodulectomía para buscar gusanos adultos o con lámpara de hendidura y observar el parásito en el ojo. Existe tratamiento farmacológico con ivermectina o quirúrgico con extracción directa de los nemátodos adultos de los oncocercomas. Los programas mundiales se basan en control vectorial y farmacoterapia. Con los conocimientos actuales y esfuerzos mundiales, la oncocercosis continúa siendo un grave problema de salud pública y causa de discapacidad. Por estas razones, se hace necesario una actualización en el tema.

Onchocerciasis is one of the neglected tropical diseases; it is produced by the filarial nematode Onchocerca volvulus and is transmitted through the bites of infected black flies of the Simulium genus. It is considered the second leading cause of preventable blindness and is present in 35 countries on three continents: Africa, America, and Asia. The following three countries have been declared free from onchocerciasis: Colombia, Ecuador, and Mexico. The main clinical manifestations are dermatological and ocular; however, lymphatic and neurological alterations have also been described. Diagnosis is made by identification of microfilariae in skin or sclerocorneal biopsy, by nodulectomy in search of adult worms, or by using a slit lamp to observe the parasite in the eye. There is pharmacological treatment through the use of ivermectin or surgical treatment by direct removal of adult nematodes from the onchocercomas. World programs are based on vector control and drug therapy. Despite current knowledge and global efforts, onchocerciasis remains a serious public health issue and an important cause of disability. Thus, an update on the topic is warranted.

A oncocercose é uma das doenças tropicais desatendidas, produzida pelo nemátodo filárico Onchocerca volvulus e transmitida pela picada da mosca negra do gênero Simulium. É considerada a segunda causa mundial de cegueira evitáveis e está presente em 35 nações de três continentes: África, América e Ásia. Existem três países declarados livres de oncocercose: Colômbia, Equador e México. As principais manifestações clínicas são dermatológicas e oculares; apesar disso, também se há descrito alterações linfáticas e neurológicas. O diagnóstico se realiza por identificação de microfilárias em biopsia da pele ou esclerocorneano, nodulectomia para buscar larva adultas ou com lâmpada de fenda e observar o parasita no olho. Existe tratamento farmacológico com ivermectina ou cirúrgico com extração direta dos nemátodos adultos dos oncocercomas. Os programas mundiais se baseiam no controle vectorial e farmacoterapia. Com os conhecimentos atuais e esforços mundiais, a oncocercose continua sendo um grave problema de saúde pública e causa de deficiência. Por estas razões, se faz necessário uma atualização no assunto.

Presencia y distribución espacial de Simulium sp. (Díptera: Simuliidae) en dos provincias de Angola / Presence and spatial distribution of Simuliumsp.(Diptera: Simuliidae) in two provinces of Angola

En el oeste de África los miembros del complejo Simulium damnosum son los vectores de la oncocercosis. El objetivo es obtener datos sobre la presencia y distribución de simúlidos en dos provincias de Angola. El trabajo se realizó en las provincias de Huambo y Bié donde se muestrearon 24 cuerpos de agua entre julio y agosto, 2015. Todos los sitios se localizaron por encima de una altitud de 1 000 m y solo tres resultaron negativos a la presencia de simúlidos. Estos resultados constituyen los primeros que se obtienen sobre la presencia y distribución espacial de Simulium sp. en Angola de gran importancia, pues la superposición de los mapas de distribución de la infección humana y los vectores permiten localizar áreas con peligro de transmisión(AU)

In West Africa Simuliumdamnosum complex members are the main vectors of onchocerciasis. The objective of this paper was to collect data on the presence and spatial distribution of black flies in two provinces of Angola. The research work was conducted in Huambo and Bié provinces where 24 water bodies were sampled between July and August 2015. All the studied sites were located above 1 000 m of altitude and only three of them were found to be negative for the presence of black flies. These were the first results obtained on the presence and spatial distribution of Simulium sp. in Angola and are of great importance because overlapping the distribution maps of human infection and of vectors allows finding the areas at risk of transmission(AU)

Water pollution and distribution of the black fly (Diptera: Simuliidae) in the Atlantic Forest, Brazil / Contaminación del agua y distribución de la mosca negra (Díptera: Simuliidae) en el bosque Atlán&tico, Brasil

Abstract:Black flies have medical importance because some species are vectors of the Onchocerciasis and Mansonelosis, nevertheless, their ecology and potential use as bioindicators is still poorly studied in the Neotropical Region. In Brazil, bioindicators use is strongly focused in a multimetrical ecological index approach; this way, we investigated the black fly spatial distribution, in relation to abiotic factors correlated to water quality, to provide baseline information for their utilization as standalone indicators of lotic systems integrity. We have tested the hypothesis that environmental changes related to urbanization, lead to decreased abundance and loss in the number of species of the black fly fauna. The sampling was conducted in 10 urban and 10 preserved streams during the dry season (August-September) of 2012, in the mountainous region of Teresópolis, State of Rio de Janeiro, Brazil. The streams were characterized for their environmental integrity conditions and physico-chemical properties of water. In each stream, five different rapid points were sampled in a section of 50 meters, 10 meters apart from each other. The black flies were sampled with a kick-net sampler on rocky substrates. The material was separated and the larvae were sorted in morphotypes, and later, the final instar specimens were dissected and identified with the help of taxonomical literature at species level. A total abundance of 488 larvae from nine species were collected, 5 (1.02 %) in extremely impacted streams, 470 (96.31 %) in intermediate streams and 13 (2.66 %) in preserved streams. The visual evaluation (HII) differed in rela&tion to the water physico-chemical evaluation, in which more variation in the characterization of the sampling sites was observed. In Canonical Correspondence Analysis Simulium subpallidum, S. inscrustatumand S. pertinaxwere significantly associated with intermediate values of most of the variables, and then to intermediate impacted sites. On the other hand, Lutzsimulium hirticosta, S. subnigrumand Simuliumsp. A were associated to low values of chemical variables, and then to more preserved sites. Most studies on the bioindicator potential of Simuliidae have suggested an approach to agricultural impacts, while our results, on the other hand, showed that Simuliidae species were present in streams with intermediate urban pollution impacts, but absent in heavily impacted sites. Thus, our data suggested that some species are associated to more pristine breeding sites, such as L. hirticostaand Simuliumsp. A, while others may be good bioindicators of moderately impacted streams, such as S. pertinax, S. subnigrumand S. subpallidum.

Resumen:Aunque las moscas negras tienen importancia médica debido a que algunas de sus especies son vectores de la Oncocercosis y Mansonelosis, su ecología y su potencial como bioindicadores es aún poco estudiado en la Región Neotropical. En Brasil el uso de bioindicadores se centra principalmente en un índice ecológico multimétrico, en este estudio investigamos la distribución espacial de las moscas negras y su relación con los factores abióticos, para su utilización como indicadores de la integridad de los sis&temas lóticos. En este sentido, hemos probado la hipótesis de que los cambios ambientales relacionados con la urba&nización conducen a la disminución de la abundancia y la pérdida de especies de la mosca negra. El muestreo se llevó a cabo en la región montañosa del Estado de Río de Janei&ro, Brasil, en 10 zonas urbanas y 10 arroyos conservados durante la estación seca (agosto-septiembre) de 2012. Los arroyos se caracterizaron por sus condiciones de integridad del ambiente y las propiedades físico-químicas de agua. Las moscas negras se muestrearon en sustratos rocosos con un kick-net sampler.El material se separó y las larvas se ordenaron por morfotipos y más tarde los especímenes en último estadio se disectaron e identificaron con la ayuda de la literatura taxonómica a nivel de especie. Una abundancia total de 488 larvas de nueve especies fueron recolectadas, 5 (1.02 %) en arroyos muy afectados, 470 (96.31 %) en intermedios y 13 (2.66 %) en conservados. La evaluación visual (HII) difiere de la físico-química del agua, en la que se observó una mayor variación. En el Análisis Correspon&dencia Canónica, Simulium subpallidum, S. inscrustatumy S. pertinaxestaban asociadas significativamente con sitios de impacto intermedio, para la mayoría de las variables. Por otro lado, Lutzsimulium hirticosta, S. subnigrumy Simuliumsp. A se asocian con valores bajos de las varia&bles químicas, relacionado a sitios más conservados. La mayoría de los estudios sobre el potencial bioindicador de Simuliidae tienden a enfocarse en los impactos agrícolas, mientras que nuestros resultados, por otro lado, sugieren que las especies de Simuliidae están presentes en arroyos con impactos intermedios de contaminación urbana, pero ausentes en los sitios fuertemente afectados. Por lo tanto, nuestros datos sugieren que algunas especies tales como L. hirticostay Simuliumsp. A están asociadas a lugares de reproducción más prístinos, mientras que otras pueden ser bioindicadores de arroyos moderadamente afectados, como S. pertinax, S. subnigrumy S. subpallidum.

Arthropod-Borne Onchocerciasis: is it deserved to be neglected?

Onchocerciasis a filarial parasitic nematode, also known as river blindness and Robles disease, is a neglected tropical disease infecting more than 18 million people mainly in subSaharan of Africa, the Middle East, South and Central America and many other countries. Disease infectivity initiates from Onchocerca volvulus [Filarioidea: Onchocercidae] transmitted by the blackfly, Simulium sp. which introduces the infective stage larva with its saliva into the skin. Within human body, adult females [macrofilaria] produce thousands of larvae [microfilariae] which migrate in skin and eye. Infection results in severe visual impairment or blindness for about 2 million, as being the world's second-leading cause of blindness after trachoma, as well as skin onchocercomata

Description of microsporidia in simulids: molecular and morphological characterization of microsporidia in the larvae of Simulium pertinax Kollar (Diptera: Simuliidae)

Introduction Microsporidia constitute the most common black fly pathogens, although the species' diversity, seasonal occurrence and transmission mechanisms remain poorly understood. Infections by this agent are often chronic and non-lethal, but they can cause reduced fecundity and decreased longevity. The objective of this study was to identify microsporidia infecting Simulium (Chirostilbia) pertinax (Kollar, 1832) larvae from Caraguatatuba, State of São Paulo, Brazil, by molecular and morphological characterization. Methods Larvae were collected at a single point in a stream in a rural area of the city and were kept under artificial aeration until analysis. Polydispyrenia spp. infection was characterized by the presence of at least 32 mononuclear spores measuring 6.9 ± 1.0 × 5.0 ± 0.7µm in persistent sporophorous vesicles. Similarly, Amblyospora spp. were characterized by the presence of eight uninucleate spores measuring 4.5 × 3.5µm in sporophorous vesicles. Results The molecular analysis confirmed the presence of microsporidian DNA in the 8 samples (prevalence of 0.51%). Six samples (Brazilian larvae) were related to Polydispyrenia simulii and Caudospora palustris reference sequences but in separate clusters. One sample was clustered with Amblyospora spp. Edhazardia aedis was the positive control taxon. Conclusions Samples identified as Polydispyrenia spp. and Amblyospora spp. were grouped with P. simulii and Amblyospora spp., respectively, corroborating previous results. However, the 16S gene tree showed a considerable distance between the black fly-infecting Amblyospora spp. and the mosquito-infecting spp. This distance suggests that these two groups are not congeneric. Additional genomic region evaluation is necessary to obtain a coherent phylogeny for this group. .

Mansonella ozzardi in the municipality of Tefé, Amazonas, Brazil, 60 years after the first report: an epidemiologic study

The prevalence of mansonelliasis was studied in the municipality of Tefé, state of Amazonas, Brazil. The prevalence (thick blood smear method) was 13.6% (147/1,078), higher in the Solimões River region (16.3%) than in the Tefé River region (6.3%). In the sampled communities in the Solimões River region, a higher density of cases was observed, as indicated by a kernel analysis (odds ratio 0.34; 95% confidence interval: 0.20-0.57). Males had a higher prevalence (χ2 = 31.292, p < 0.001) than women. Mansonella ozzardi prevalence was higher in retirees and farmers (28.9% and 27%, respectively). Prevalence also significantly increased with age (χ2 = -128.17, p < 0.001), with the highest numbers occurring in persons older than 67 years.

New records of Mansonella ozzardi: a parasite that is spreading from the state of Amazonas to previously uninfected areas of the state of Acre in the Purus River region

Mansonella ozzardi infections are common in the riverside communities along the Solimões, 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.

Aspectos bioecológicos de Simuliidae em área sob influência de empreendimento hidroenergético: aproveitamento múltiplo de Manso, MT, Brasil / Bioecology of Simuliidae in area under influence of hydropower development: multiple uses of Manso, MT, Brazil

Devido às condições hidrogeográficas brasileiras favoráveis a instalação de hidrelétricas, este tipo de empreendimento é responsável pela maior parte da produção de energia do País. Estas hidrelétricas impactam diretamente os criadouros de insetos aquáticos, inclusive os de simulídeos. O monitoramento de Simuliidae, em especial em áreas com alto grau de biodiversidade e com fauna ainda pouco estudada, como o Bioma Cerrado, é de extrema importância para a prospecção de dados relevantes para o conhecimento da biodiversidade alinhado com a saúde pública. O Aproveitamento Múltiplo de Manso está localizado em área de Cerrado no município de Chapada dos Guimarães, atingindo também Cuiabá e Nova Brasilândia, MT. Para o monitoramento de Simuliidae, foram realizadas 13 coletas bimestrais em períodos de seca e chuva de maio/2009 a julho/2011. Do total de pontos selecionados na área sob influência direta, 11 pontos foram a montante e 03 a jusante da barragem e 05 pontos, aparentemente, sem influência direta do APM Manso. De maneira geral, percebe-se que o número total de exemplares coletados é inversamente proporcional à precipitação acumulada do período. No total, foram encontradas 28 espécies: Simulium brunnescens, S. pertinax, S. (Chirostilbia) sp, S. spinibranchium, S. dekeyseri, S. subpallidum, S. perflavum, S. (Psilopelmia) sp, S. rorotaense, S. incrustatum sl, S. quadrifidum, S. jujuyense, S. incrustatum s.s., S. limbatum, S. minusculum sl, S. oyapockense, S. (Psaroniocompsa) sp, S. cuasiexiguum, S. (Notolepria) sp, S. guianense, S. nigrimanum, S. rubrithorax, S. (Trichodagmia) sp, S. inaequale, S. clavibranchium sl, S. (Inaequalium) sp, S. subclavibranchium e S. subnigrum. Todas as espécies, com a exceção de S. quadrifidum e S. clavibranchium, já haviam sido registradas para o estado do Mato Grosso. S. perflavum, S. subnigrum e S. subclavibranchium foram encontradas em todas as campanhas...

Simulium (Chirostilbia) brunnescens (Diptera: Simuliidae) - new species from the Brazilian cerrado, Manso Dam, state of Mato Grosso, Brazil

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.

Dermatitis de pabellón auricular por picadura de jerjeles: Una entidad clínica diferente no descrita / Dermatitis of the pinna by puncture of the black fly: A different clinical disease not yet described

Introducción: La picadura de jerjeles o simúlidos de la cara anterior del pabellón auricular presenta características clínicas diferente a las picaduras del mismo insecto en la piel del resto del cuerpo y requiere también un tratamiento diferente. Estos hechos no han sido descritos en la literatura. Objetivos: El objetivo es detallar los síntomas y signos de estas picaduras y las causas de las diferencias clínicas y de su tratamiento. Material y método: Para ello se hace el estudio y análisis de 6 pacientes aquejados por picaduras de jerjeles en la cara anterior de la oreja. Se investiga la biología de estos simúlidos. Finalmente se hace una revisión de la histología de la piel que recubre el cartílago auricular. Resultados: El síntoma principal de todos los pacientes fue un intenso dolor y edema de la oreja que les impedía dormir. La razón principal de estos síntomas es la íntima adhesión del dermis al cartílago auricular y que forma el pericondrio de éste, además de las múltiples toxinas salivales del insecto que tienen propiedades anticoagulantes, vasodilatadoras, e inhibidoras de la inmunidad celular. Conclusiones: Las plagas de jerjeles y sus picaduras serán cada vez más numerosas en Chile debido al calentamiento global, la destrucción de los ecosistemas por el hombre que han ido eliminando sus enemigos naturales y la contaminación de la casi totalidad de ríos y lagos de nuestro país. Para el tratamiento de las picaduras de jerjeles del pabellón auricular es necesario recurrir al uso de corticoesteroides en dosis altas y por períodos breves de menos de una semana.

Introduction: Puncture of the black fly or dipteral simuliidae on the external surface of the ear auricle shows clinical characteristics which differ from the puncture of this same insect on other different parts of the body Thus, it requires a different treatment, as well. These facts have not been clinically described yet, therefore, there is no literature available on this topic. Aim: To describe symptoms and signs of this disease.To outline the causes of the clinical differences and medical treatment. Material and method: Study and analysis of six patients suffering from puncture of black fly on the surface of ear auricle are carried out. The biology of these insects is studied. A revision of the histology of the skin of the ear auricle is made Results: The main symptoms experimented by patients suffering from black fly puncture are: excruciating pain and severe edema on the auricle area. The pain even prevents them from sleeping. The main cause of these symptoms is that the skin on the external surface of the auricle is firmly attaches to the underlying cartilage. Besides, the countless toxins inoculated in the saliva of the fly contain not only anticoagulant agents but also produce vasodilatation of capillaries and inhibit cellular immunity. Conclusions: The black fly plague and its infectious and painful puncture will be on the increase in Chile due to: global warming; elimination of the natural predators of this insect; man induced pollution of the majority of lakes and rivers in the country. The medical treatment for black fly puncture indicates corticosteroids in high dose for a short period of time (under a week).

Evolution of insecticide resistance in non-target black flies (Diptera: Simuliidae) from Argentina

Black flies, a non-target species of the insecticides used in fruit production, represent a severe medical and veterinary problem. Large increases in the level of resistance to the pyrethroids fenvalerate (more than 355-fold) and deltamethrin (162-fold) and a small increase in resistance to the organophosphate azinphos methyl (2-fold) were observed between 1996-2008 in black fly larvae under insecticide pressure. Eventually, no change or a slight variation in insecticide resistance was followed by a subsequent increase in resistance. The evolution of pesticide resistance in a field population is a complex and stepwise process that is influenced by several factors, the most significant of which is the insecticide selection pressure, such as the dose and frequency of application. The variation in insecticide susceptibility within a black fly population in the productive area may be related to changes in fruit-pest control. The frequency of individuals with esterase activities higher than the maximum value determined in the susceptible population increased consistently over the sampling period. However, the insecticide resistance was not attributed to glutathione S-transferase activity. In conclusion, esterase activity in black flies from the productive area is one mechanism underlying the high levels of resistance to pyrethroids, which have been recently used infrequently. These enzymes may be reselected by currently used pesticides and enhance the resistance to these insecticides.

Diversidade de Simuliidae (Diptera: Nematocera) de três cursos d’água no parque ecológico da Klabin S.A. – Telêmaco Borba, Estado do Paraná / Simuliidae diversity (Diptera: Nematocera) of three water courses in Klabin’s ecological park – Telêmaco Borba, State of Paraná

Os simulídeos têm sido objeto de preocupação devido ao seu hábito hematófago, forte antropofilia e alta proliferação, causando desconforto à população, prejuízos em atividades agropecuárias e de turismo rural, além de serem vetores de patógenos. Objetivando conhecer a estrutura de comunidade e diversidade específica desses insetos, foi realizado o levantamento de espécies em três riachos de um parque ecológico em Telêmaco Borba – Paraná. Coletaram-se imaturos em substratos minerais e vegetais no leito dos rios. Efetuaram-se análises físicas e químicas da água. Foram coletados 14397 indivíduos, sendo 14150 larvas e 247 pupas de simulídeos. Identificaram-se as espécies Simullium subnigrum, S. subpallidum, S. rubrithorax, S. incrustatum, S. pertinax, S. inaequale, S. anamariae, S. rubiginosum, S. travassosi, S. riograndense e S. dinelli. Este é o primeiro registro de S. rubiginosum e S. dinelli para o Estado do Paraná. As áreas de menor impacto apresentaram maior diversidade, entretanto áreas impactadas apresentaram maior abundância de borrachudos, representados por apenas uma espécie, S. rubrithorax. Conclui-se que áreas de preservação com ribeirões de águas lóticas e mata ciliar preservada constituem-se como área de refúgio para as espécies de simulídeos. Ambientes antropofizados interferem na dinâmica das espécies, privilegiando uma ou mais, que tornam-se abundantes e dominantes do criadouro. .

Simuliidae have been considered object of concern due to their hemophagia, anthropophilic habits and high proliferation, causing discomfort to the population, damages to agricultural activities and rural tourism, besides being pathogens vectors. With the purpose of understanding the community structure and specific diversity of these insects, a survey of the species was conducted in three streams in an ecological park in Telêmaco Borba – Paraná, Brazil. Immature specimens were collected in mineral and vegetable substrates on the riverbanks. Chemical and physical analyses of the water were carried out. The Simuliidae collection included 14,397 individuals, being 14,150 larvae and 247 pupae. The following species were identified: Simullium subnigrum, S. subpallidum, S. rubrithorax, S. incrustatum, S. pertinax, S. inaequale, S. anamariae, S. rubiginosum, S. travassosi, S. riograndense and S. dinelli.This is the first registry of S. rubiginosum and S. dinelli in the State of Paraná. The lesser-impacted areas presented greater diversity. However, the impacted areas presented an abundance of borrachudos, represented by a single species, S. rubrithorax. It was concluded that preservation areas with lotic waters and riparian forest are considered a refuge area for Simuliidae species. Impact of anthropical activities upon the environment interferes in the dynamics of species, favoring one or more of them, which proliferate and predominate. .

Diversity and microdistribution of black fly (Diptera: Simuliidae) assemblages in the tropical savanna streams of the Brazilian cerrado

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.

The phylogeny of Simulium (Chirostilbia) (Diptera: Simuliidae) and perspectives on the systematics of the genus in the Neotropical Region

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.