Helder Ricas Rezende

Criadouros de Aedes (Stegomyia) aegypti (Linnaeus, 1762) em bromélias nativas na Cidade de Vitória, ES

Some insects that are vectors of human diseases have accompanied man in his migrations throughout the world and breed exclusively in the proximity of human dwellings. The mosquito Aedes aegypti has been responsible for epidemics of dengue in Brazil and its presence also constitutes a serious risk for future outbreaks of urban yellow fever. The failure of campaigns to eradicate this species justifies the search for alternative breeding sites, which may be beyond the reach of present control measures. In this study the occurrence of Aedes aegypti breeding sites in native bromeliads on rocky slopes was investigated in five areas of Vitoria, capital of the Brazilian State of Espirito Santo, ES. Water contained in the bromeliads was collected with the aid of a suction apparatus to search for culicid larvae. The degree of infestation of buildings in adjacent urban areas was evaluated simultaneously. Culicid larvae were found in bromeliads in four of the five areas investigated, Aedes aegypti being present in two areas. The presence of breeding sites in bromeliads was not related to indices of infestation of buildings in adjacent areas. Further studies are necessary to define whether breeding sites in bromeliads constitute primary foci of Aedes aegypti, or are a consequence of high infestation levels in urban areas.

Entomological characterization and natural infection of anophelines in an area of the Atlantic Forest with autochthonous malaria cases in mountainous region of Espírito Santo State, Brazil

Autochthonous malaria cases in the state of Espírito Santo, Brazil, are distributed in mountainous regions surrounded by the Atlantic Forest. While some aspects of this disease are unclear, detection of possible vector species can help to elucidate epidemiological uncertainties. Entomological and natural infection studies were carried out using anophelines (Diptera: Culicidae) captured in the municipality of Santa Tereza, ES. Monthly captures were made from March 2004 to February 2006. CDC-CO2 traps were used from dusk (6:00 P.M.) to dawn (6:00 A.M.) to capture anophelines in the following habitats: near the houses, in open areas (at ground level) and inside, and at the margins of the forest (canopy and ground level). Shannon light traps were also used at the same locations of the CDC-CO2 traps. A total of 2,290 anophelines within 10 species were captured. The relative frequency of Anopheles (Kerteszia) cruzii Dyar & Knab / A.(K.) homunculus Komp was the highest, with the majority captured in CDC-CO2 traps installed in the forest canopy. The main species captured in Shannon traps was A.(Nyssorhynchus) strodei Root. The largest number of anophelines was captured from July to September and from 6:00 P.M. to 10:00 P.M. Anopheles (K.) cruzii is the probable vector for malaria transmission inside or near the Atlantic Forest fragments, but the role of other species cannot be ignored, as 53% of the sampled anophelines belonged to the subgenus Nyssorhynchus. The natural infection of A. cruzii, A. parvus (Chagas) and A. galvaoi Causey, Deane & Deane by Plasmodium vivax detected by PCR from DNA extracted from their thoraxes supports this view.

Effects of the installation of the Rosal hydroelectric power station, Itabapoana River, States of Espírito Santo and Rio de Janeiro, on anophelinae, planorbidae and phlebotominae

The construction of dams usually changes the composition of the fauna within their areas of influence. In the area where the Rosal hydroelectric power station has been installed, in the States of Espírito Santo and Rio de Janeiro, changes to the abundance of anophelinae, planorbidae and phlebotominae were evaluated before (1998-2000) and after (2000-2005) the damming. Nine sample collection points were defined, each represented by a home and its outbuildings, shelters for domestic animals and water collection points within a radius of 150m. One hundred and three adult anophelinae were collected before the damming and 313 afterwards; 200 immature anophelinae before and 708 afterwards; 868 planorbidae before and 486 afterwards; and 2,979 phlebotominae before and 912 afterwards. The vector record, consisting of anophelinae, planorbidae and phlebotominae, shows the potential of this area for transmission of malaria, schistosomiasis and American cutaneous leishmaniasis. However, the environmental changes did not increase the risk of the occurrence of these diseases.

DNA Barcoding of Neotropical Sand Flies (Diptera, Psychodidae, Phlebotominae): Species Identification and Discovery within Brazil

DNA barcoding has been an effective tool for species identification in several animal groups. Here, we used DNA barcoding to discriminate between 47 morphologically distinct species of Brazilian sand flies. DNA barcodes correctly identified approximately 90% of the sampled taxa (42 morphologically distinct species) using clustering based on neighbor-joining distance, of which four species showed comparatively higher maximum values of divergence (range 4.23–19.04%), indicating cryptic diversity. The DNA barcodes also corroborated the resurrection of two species within the shannoni complex and provided an efficient tool to differentiate between morphologically indistinguishable females of closely related species. Taken together, our results validate the effectiveness of DNA barcoding for species identification and the discovery of cryptic diversity in sand flies from Brazil.

Aspectos atuais da distribuição geográfica de Anopheles (Kerteszia) cruzii Dyar & Knab, 1908 no estado do Espírito Santo, Brasil

Anopheles cruzii was registered in Espirito Santo state both in 1957 and 1968. Our study provides additional evidence of its presence, including municipalities that were non mentioned before. Anopheles captures undertaken between 1998 and 2003 pointed out a distribution restricted to the forested outskirts of the mountains in the highland area of the state. Its epidemiological role is suggested by the simultaneous presence of malaria cases in the same municipalities.

Breeding sites of Aedes aegypti in metropolitan vacant lots in Greater Vitória, State of Espírito Santo, Brazil

INTRODUCTION This study aimed to evaluate the presence of Aedes aegypti in breeding sites located in vacant lots (VLs) and determine the effectiveness of VL cleaning to reduce insect foci. METHODS Two types of VLs were sampled, the experimental VL, which was cleaned monthly, and the control VL, which was not cleaned. RESULTS Monthly cleaning of VLs reduced the abundance of immature forms of A. aegypti. CONCLUSIONS Strategies for combating this vector should include regular cleaning of VLs and educating the public regarding the risks of discarding waste in inappropriate areas.

Mitochondrial genome of Plasmodium vivax/simium detected in an endemic region for malaria in the Atlantic Forest of Espírito Santo state, Brazil: do mosquitoes, simians and humans harbour the same parasite?

BackgroundThe transmission of malaria in the extra-Amazonian regions of Brazil, although interrupted in the 1960s, has persisted to the present time in some areas of dense Atlantic Forest, with reports of cases characterized by particular transmission cycles and clinical presentations. Bromeliad-malaria, as it is named, is particularly frequent in the state of Espírito Santo, with Plasmodium vivax being the parasite commonly recognized as the aetiologic agent of human infections. With regard to the spatial and temporal distances between cases reported in this region, the transmission cycle does not fit the traditional malaria cycle. The existence of a zoonosis, with infected simians participating in the epidemiology, is therefore hypothesized. In the present study, transmission of bromeliad-malaria in Espírito Santo is investigated, based on the complete mitochondrial genome of DNA extracted from isolates of Plasmodium species, which had infected humans, a simian from the genus Allouata, and Anopheles mosquitoes. Plasmodium vivax/simium was identified in the samples by both nested PCR and real-time PCR. After amplification, the mitochondrial genome was completely sequenced and compared with a haplotype network which included all sequences of P. vivax/simium mitochondrial genomes sampled from humans and simians from all regions in Brazil.ResultsThe haplotype network indicates that humans and simians from the Atlantic Forest become infected by the same haplotype, but some isolates from humans are not identical to the simian isolate. In addition, the plasmodial DNA extracted from mosquitoes revealed sequences different from those obtained from simians, but similar to two isolates from humans.ConclusionsThese findings strengthen support for the hypothesis that in the Atlantic Forest, and especially in the state with the highest frequency of bromeliad-malaria in Brazil, parasites with similar molecular backgrounds are shared by humans and simians. The recognized identity between P. vivax and P. simium at the species level, the sharing of haplotypes, and the participation of the same vector in transmitting the infection to both host species indicate interspecies transference of the parasites. However, the intensity, frequency and direction of this transfer remain to be clarified.

Sand fly fauna (Diptera: Psychodidae) from the Goytacazes National Forest and surrounding areas of southeastern Brazil

ABSTRACT: Most studies of the sand fly fauna in southeastern Brazil are conducted in the peridomiciliary environment of leishmaniasis endemic regions. Therefore, to increase the knowledge about diversity and richness of sand fly conservation areas, we describe here the sand fly fauna from the National Forest of Goytacazes (NFG), state of Espírito Santo, Brazil, and its surroundings areas. We also used sand fly fauna records from eight conservations units within the state of Espírito Santo to understand the similarity and relationships among them. The sand flies were simultaneously collected from June, 2008 to May, 2009 in two different environments: a preserved environment represented by the NFG and a modified environment represented by a peridomicile. To establish the similarity among the conservation units, we used a method very similar to parsimony analysis of endemism. We collected 2,466 sand fly specimens belonging to 13 species. Pressatia choti and Nyssomyia intermedia were the most abundant sand fly species. Ny. intermedia is a known vector of Leishmania braziliensis and epidemiological surveillance must be conducted in the area. We discuss aspects regarding the diversity of sand flies as well as the risk of transmission of Leishmania parasites in the area. We also provide for the first time a hypothesis of similarity relationships among conservation units within the state of Espírito Santo.

Aspectos ecológicos de culicídeos imaturos em larvitrampas de floresta e ambiente antrópico adjacente no Município de Linhares, Espírito Santo, Brasil

Resumo Objetivo: verificar a ocorrencia de especies de culicideos que colonizam larvitrampas. Metodologia: a pesquisa foi realizada na Floresta Nacional de Goytacazes e ambiente antropico adjacente, situados no municipio de Linhares, Estado do Espirito Santo, Brasil; foram instaladas larvitrampas no solo e copa de arvores na estrada dentro do ambiente florestal e no antropico proximo de residencia humana. Resultados: entre junho de 2008 a maio de 2009, foram coletados 664 especimes e Limatus durhami foi a predominante, principalmente nas larvitrampas do solo; na copa de arvores do ambiente florestal, os Culex spp. foram mais frequentes, seguidos por Haemagogus leucocelaenus. Conclusao: os dados mostram que os culicideos silvestres podem procriar em recipientes artificiais, o que aumenta o risco de contato homem-vetor; o encontro de H. leucocelaenus reveste-se de importância epidemiologica, pelo envolvimento na transmissao da febre amarela silvestre. Palavras-chave: ecologia de vetores; febre amarela silvestre; Haemagogus leucocelaenus; recipiente artificial.

Ecological characterisation and infection of Anophelines (Diptera: Culicidae) of the Atlantic Forest in the southeast of Brazil over a 10 year period: has the behaviour of the autochthonous malaria vector changed?

BACKGROUND In southeastern Brazil, autochthonous cases of malaria can be found near Atlantic Forest fragments. Because the transmission cycle has not been completely clarified, the behaviour of the possible vectors in those regions must be observed. A study concerning the entomological aspects and natural infection of anophelines (Diptera: Culicidae) captured in the municipalities of the mountainous region of Espírito Santo state was performed in 2004 and 2005. Similarly, between 2014 and 2015, 12 monthly collections were performed at the same area of the study mentioned above. METHODS Center for Disease Control (CDC) light traps with CO2 were set in open areas, at the edge and inside of the forest (canopy and ground), whereas Shannon traps were set on the edge. FINDINGS A total of 1,414 anophelines were collected from 13 species. Anopheles (Kerteszia) cruzii Dyar and Knab remained the most frequently captured species in the CDC traps set in the forest canopy, as well as being the vector with the highest prevalence of Plasmodium vivax/simium infection, according to molecular polymerase chain reaction techniques. CONCLUSIONS P. vivax/simium was found only in abdomens of the mosquitoes of the subgenus Nyssorhynchus, weakening the hypothesis that this subgenus also plays a role in malaria transmission in this specific region.