Brazilian mosquito (Diptera: Culicidae) fauna: I. Anopheles species from Porto Velho, Rondônia state, western Amazon, Brazil

This study contributes to knowledge of Anopheles species, including vectors of Plasmodium from the western Brazilian Amazon in Porto Velho, Rondônia State. The sampling area has undergone substantial environmental changes as a consequence of agricultural and hydroelectric projects, which have caused intensive deforestation and favored habitats for some mosquito species. The purpose of this study was to diagnose the occurrence of anopheline species from collections in three locations along an electric-power transmission line. Each locality was sampled three times from 2010 to 2011. The principal adult mosquitoes captured in Shannon trap were Anopheles darlingi, An. triannulatus, An. nuneztovari l.s., An.gilesi and An. costai. In addition, larvae were collected in ground breeding sites for Anopheles braziliensis, An. triannulatus, An. darlingi, An. deaneorum, An. marajoara, An. peryassui, An. nuneztovari l.s. and An. oswaldoi-konderi. Anopheles darlingi was the most common mosquito in the region. We discuss Culicidae systematics, fauna distribution, and aspects of malaria in altered habitats of the western Amazon.

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

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.

Essays on the history of Brazilian dipterology: II. notices about Brazilian Diptera (17th century)

Essays on the history of Brazilian dipterology. II. Notices about Brazilian Diptera (17th century). Notices from the Brazilian Diptera from the 17th century come mainly from two foreign invasions occurred in Brazil, the first one by the French in Maranhão and the second by the Dutch in northeastern Brazil. This paper includes reports of Fathers Claude d'Abbeville and Yves d'Evreux and from Piso and Marcgrave, the last two presenting the first illustrations of Brazilian Diptera. The paper also includes reports of Friar Laureano de la Cruz, Father João de Sotto Mayor and Maurício de Heriarte.

New protein sources in adults diet for mass-rearing of Anastrepha fraterculus (Diptera:Tephritidae)

The aim of this study was to find alternatives to reduce the cost of mass production of the South American fruit fly (A. fraterculus) by looking for locally available products as protein source in the diet of adults to replace the imported product without changing the quality parameters. Two yeast from a Brazilian company were evaluated. The quality parameters showed that the imported hydrolyzed yeast used in the adult diet could be perfectly replaced by the local products tested, with a reduction of over 80% of the cost of the diet. The quality of the produced insects remained the same and there were improvements in some quality parameters such as the volume of eggs produced, number of adults flying and longevity under the stress.

Species of Drosophila (Diptera: Drosophilidae) attracted to dung and carrion baited pitfall traps in the Uruguayan Eastern Serranías

This study investigates the species richness and abundance of Drosophila Fallén, 1823 attracted to dung and carrion baited pitfall traps in natural areas with heterogeneous habitats at the Sierra de Minas, Eastern Serranías, southeastern Uruguay. Collecting was carried out on a monthly basis (May 2002 through April 2003). Drosophilids accounted for 0.84% (n = 131) and 3.61% (n = 158) of the Diptera collected from dung (n = 15,630) and carrion (n = 4,382) pitfall traps, respectively. A total of 12 species were identified, 11 of which belong to the subgenus Drosophila (the richest) and one to the subgenus Sophophora Sturtevant, 1939. Over 90% of the Drosophila specimens collected belong to five species of the subgenus Drosophila, namely D. gaucha Jaeger & Salzano, 1953, D. immigrans Sturtevant, 1921, D. mediovittata Frota-Pessoa, 1954, D. aff. nappae Vilela, Valente & Basso-da-Silva, 2004, and D. ornatifrons Duda, 1927. Drosophila cardini Sturtevant, 1916 is recorded for the first time from Uruguay. Drosophila abundance and species richness in the four habitats sampled in the Uruguayan Eastern Serranías, namely woodlands sierra, riparian forest, pine plantation and grazing grassland, were considered to be a function of habitat conservation. Diversity indices were low in all habitats. Different habitats supported particular coprophilous and necrophilous Drosophila species. The woodland sierra represents the most preserved habitat, and contributed with the highest species richness observed. Drosophila ornatifrons was the dominant species, with a restricted habitat distribution. On the other hand, grazed grassland, an environment modified by livestock management, had the lowest species richness: only a few specimens of D. repleta Wollaston, 1858. Regarding species composition, significant differences were found in some pairwise comparisons of groups of Drosophila species that included D. ornatifrons. Fly attraction to dung can be exploited as an alternative and/or complementary collecting method in ecological studies of Drosophila assemblages in natural areas.

Chromatin Structure of Ribosomal RNA Genes in Dipterans and Its Relationship to the Location of Nucleolar Organizers

Nucleoli, nuclear organelles in which ribosomal RNA is synthesized and processed, emerge from nucleolar organizers (NORs) located in distinct chromosomal regions. In polytene nuclei of dipterans, nucleoli of some species can be observed under light microscopy exhibiting distinctive morphology: Drosophila and chironomid species display well-formed nucleoli in contrast to the fragmented and dispersed nucleoli seen in sciarid flies. The available data show no apparent relationship between nucleolar morphology and location of NORs in Diptera. The regulation of rRNA transcription involves controlling both the transcription rate per gene as well as the proportion of rRNA genes adopting a proper chromatin structure for transcription, since active and inactive rRNA gene copies coexist in NORs. Transcription units organized in nucleosomes and those lacking canonical nucleosomes can be analyzed by the method termed psoralen gel retarding assay (PGRA), allowing inferences on the ratio of active to inactive rRNA gene copies. In this work, possible connections between chromosomal location of NORs and proportion of active rRNA genes were studied in Drosophila melanogaster, and in chironomid and sciarid species. The data suggested a link between location of NORs and proportion of active rRNA genes since the copy number showing nucleosomal organization predominates when NORs are located in the pericentric heterochromatin. The results presented in this work are in agreement with previous data on the chromatin structure of rRNA genes from distantly related eukaryotes, as assessed by the PGRA.

Factors Associated with Dengue Mortality in Latin America and the Caribbean, 1995-2009: An Ecological Study

In this study, we aimed to estimate the effect that environmental, demographic, and socioeconomic factors have on dengue mortality in Latin America and the Caribbean. To that end, we conducted an observational ecological study, analyzing data collected between 1995 and 2009. Dengue mortality rates were highest in the Caribbean (Spanish-speaking and non-Spanish-speaking). Multivariate analysis through Poisson regression revealed that the following factors were independently associated with dengue mortality: time since identification of endemicity (adjusted rate ratio [aRR] = 3.2 [for each 10 years]); annual rainfall (aRR = 1.5 [for each 10(3) L/m(2)]); population density (aRR = 2.1 and 3.2 for 20-120 inhabitants/km(2) and > 120 inhabitants/km(2), respectively); Human Development Index > 0.83 (aRR = 0.4); and circulation of the dengue 2 serotype (aRR = 1.7). These results highlight the important role that environmental, demographic, socioeconomic, and biological factors have played in increasing the severity of dengue in recent decades.

NEW RECORDS OF MOSQUITOES FROM NORTHWESTERN ARGENTINA

Eleven mosquito species, namely Aedes hastatus, Ae. fulvus, Coquillettidia albicosta, Cq. juxtamansonia, Culex aliciae, Cx. delpontei, Cx. oedipus, Cx. pedroi, Mansonia flaveola, Uranotaenia leucoptera, and Wyeomyia oblita, are recorded for the first time from northwestern Argentina. In addition, 3 species, Cx. brethesi, Limatus durhami, and Ur. nataliae, are reported for the first time from Salta Province. These records extend the geographical distribution of these 3 species to Salta Province. This study also extends the geographical distributions of Cq. nigricans, Cx. chidesteri, and Ma. humeralis to Jujuy Province and of Ae. meprai, Ae. milleri, Ae. oligopistus, Cx. brethesi, Cx. fernandezi, and Cx. tatoi to Tucuman Province.

Parasitoids (Braconidae) associated with Anastrepha (Tephritidae) in host fruits on the Southern coast of Bahia, Brazil

Among the organisms acting in the natural biological control of tephritids, members of the family Braconidae are the most active form of natural parasite, and in Neotropical regions, members of Opiinae are the main control agents of Anastrepha. The objective of this work was to discover the percentage of parasitism and the species of braconid associated with fruit trees growing in cities on the southern coast of Bahia. During the period of August, 2005 to March, 2008, hosts fruits of fruit flies from several plant species were collected and from the fruits the following species of Anastrepha were obtained: A. fraterculus, A. obliqua, A. bahiensis, A. serpentina, A. sororcula and A. zenildae. Of the total of 838 specimens of braconids, 21.36% were of the species Utetes anastrephae (Viereck), obtained from yellow mombin, carambola, guava, mango and pitanga; 4.42% were of the species Asobara anastrephae (Muesebeck) obtained from the fruits of the yellow mombin, carambola and guava, and only one example of Opius bellus Gahan (0.12%) that came from a guava sample. The species Doryctobracon areolatus (Szepligeti) (74.10%) was predominant and emerged from puparia from all the host fruits collected, probably due to the greater efficiency of this species in locating tephritid larvae. The mean percentage of parasitism by Anastrepha spp. was 4.45%.

Amazonian malaria: Asymptomatic human reservoirs, diagnostic challenges, environmentally driven changes in mosquito vector populations, and the mandate for sustainable control strategies

Across the Americas and the Caribbean, nearly 561,000 slide-confirmed malaria infections were reported officially in 2008. The nine Amazonian countries accounted for 89% of these infections; Brazil and Peru alone contributed 56% and 7% of them, respectively. Local populations of the relatively neglected parasite Plasmodium vivax, which currently accounts for 77% of the regional malaria burden, are extremely diverse genetically and geographically structured. At a time when malaria elimination is placed on the public health agenda of several endemic countries, it remains unclear why malaria proved so difficult to control in areas of relatively low levels of transmission such as the Amazon Basin. We hypothesize that asymptomatic parasite carriage and massive environmental changes that affect vector abundance and behavior are major contributors to malaria transmission in epidemiologically diverse areas across the Amazon Basin. Here we review available data supporting this hypothesis and discuss their implications for current and future malaria intervention policies in the region. Given that locally generated scientific evidence is urgently required to support malaria control interventions in Amazonia, we briefly describe the aims of our current field-oriented malaria research in rural villages and gold-mining enclaves in Peru and a recently opened agricultural settlement in Brazil. (C) 2011 Elsevier B.V. All rights reserved.

NEW RECORDS OF ANOPHELES HOMUNCULUS IN CENTRAL AND SERRA DO MAR BIODIVERSITY CORRIDORS OF THE ATLANTIC FOREST, BRAZIL

Two new records of Anopheles homunculus in the eastern part of the Atlantic Forest are reported. This species was found for the first time in Barra do Ouro district, Maquine municipality, Rio Grande do Sul state, located in the southern limit of the Atlantic Forest. The 2nd new record was in the Serra Bonita Reserve, Camacan municipality, southeast Bahia state. These records extend the geographical distribution of An. homunculus, suggesting that the species may be widely distributed in coastal areas of the Atlantic Forest. It is hypothesized that the disjunct distribution of the species may be caused by inadequate sampling, and also difficulties in species identification based only on female external characteristics. Species identification was based on morphological characters of the male, larva, and pupa, and corroborated by DNA sequence analyses, employing data from both 2nd internal transcribed spacer of nuclear ribosomal DNA and of mitochondrial cytochrome c oxidase subunit I.

First Identification of Culex flavivirus (Flaviviridae) in Brazil

Introduction: Culex flavivirus (CxFV) was first isolated in 2007 from Culex pipiens in Japan and then identified in several other countries. Characterization of the CxFV showed that all strains are related to the cell fusing agent virus. In this manuscript we report the first identification of CxFV in South America. Material and Methods: We have collected Culex sp. mosquitoes using BG-Sentinel traps and manual aspirators. They were pooled according to genus, species, sex and location. Viral RNA was extracted and multiplex nested PCR was performed to test the presence of Flavivirus. The positive samples were isolated in C6/36 cells and sequenced for phylogenetic analyses. Results: 265 female Culex mosquitoes pooled in 83 pools were tested with specific CxFV, Saint Louis encephalitis virus (SLEV) and West Nile virus (WNV) primers. Our sequence data indicated maximum sequence similarity of 97% with CxFV. Discussion: In this study we report the circulation of CxFV in an urban setting where SLEV had previously caused an outbreak. In terms of public health, this is an important finding due to the assumption that the previous exposition of mosquitoes to CxFV might lessen the susceptibility of these mosquitoes to other flaviviruses. Copyright (C) 2012 S. Karger AG, Basel

Leishmania (Viannia) braziliensis is the main species causing cutaneous leishmaniasis in the Federal District of Brazil

The first autochthonous case of American cutaneous leishmaniasis was reported in the Federal District in 1980, and the species involved in this type of leishmaniasis was unknown. This study aimed to identify the species that causes the disease in the Federal District and to investigate its clinical and epidemiological aspects. Between 2000 and 2007, 71 autochthonous cases of leishmaniasis were reported in the Federal District. Leishmania species were identified by means of direct immunofluorescence reactions using monoclonal antibodies and restriction fragment length polymorphism. The species of 40 (56.33%) out of 71 samples were identified. Thirty-six (90%) were identified as Leishmania (Viannia) braziliensis and four (10%) were identified as Leishmania (Leishmania) amazonensis. In this area, the disease had clinical and epidemiological characteristics similar to those found in other Brazilian regions.

Integrodifference model for blowfly invasion

We propose a stage-structured integrodifference model for blowflies' growth and dispersion taking into account the density dependence of fertility and survival rates and the non-overlap of generations. We assume a discrete-time, stage-structured, model. The spatial dynamics is introduced by means of a redistribution kernel. We treat one and two dimensional cases, the latter on the semi-plane, with a reflexive boundary. We analytically show that the upper bound for the invasion front speed is the same as in the one-dimensional case. Using laboratory data for fertility and survival parameters and dispersal data of a single generation from a capture-recapture experiment in South Africa, we obtain an estimate for the velocity of invasion of blowflies of the species Chrysomya albiceps. This model predicts a speed of invasion which was compared to actual observational data for the invasion of the focal species in the Neotropics. Good agreement was found between model and observations.

Oral myiasis in an elderly patient

Background: Myiasis is the invasion of living tissue of humans and other mammals by eggs or maggots of flies of the order of Diptera. It occurs mainly in the Tropics and is associated with inadequate public and personal hygiene. Oral myiases in an older man appears to be rare. Objective: To relate a case of oral myiases in a debilitated older man treated by mechanical removal of the maggots, identifying the adult insect that caused the infestation. Methods: The diagnosis of oral myiasis was established by the clinical examination and it was detected that the infestation involved only soft tissue and the sinus cavity. The patient was submitted to two mechanical removal of the visible maggots. Results: Total of 110 maggots was removed from the oral cavity of the patient and adult insects was identified as belonging to the Calliphoridae Family, Cochliomyia hominivorax species. The patient died two days after the second procedure by severe systemic complications. Conclusions: The mechanic removal and the identification of the maggots must be adopted as soon as possible to prevent further tissue damage and bacterial infection in cases of oral myiasis. Special attention should be given to the debilitated old patients that are particularly susceptible to oral myiasis infestation.