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SummaryMalaria remains one of the most devastating infectious diseases. Reverse genetic screens offer a powerful approach to identify genes and molecular processes governing malaria parasite biology. However, sexual reproduction and complex regulation of gene expression and genotype-phenotype associations in the mosquito have hampered the development of screens in this key part of the parasite lifecycle. We designed a genetic approach in the rodent parasitePlasmodium berghei, which in conjunction with barcode sequencing allowed us to overcome the fertilization roadblock and screen for gametocyte-expressed genes required for parasite infection of the mosquitoAnopheles coluzzii. The results confirmed previous findings, validating our approach for scaling up, and identified new genes required for ookinete motility and mosquito midgut infection and for sporozoite development and oocyst egress and salivary gland infection. Our findings can assist efforts to study malaria transmission biology and develop new interventions to control disease transmission.

Background Whole genome re-sequencing provides powerful data for population genomic studies, allowing robust inferences of population structure, gene flow and evolutionary history. For the major malaria vector in Africa, Anopheles gambiae, other genetic aspects such as selection and adaptation are also important. In the present study, we explore population genetic variation from genome-wide sequencing of 765 An. gambiae and An. coluzzii specimens collected from across Africa. We used t-SNE, a recently popularized dimensionality reduction method, to create a 2D-map of An. gambiae and An. coluzzii genes that reflect their population structure similarities. Results The map allows intuitive navigation among genes distributed throughout the so-called “mainland” and numerous surrounding “island-like” gene clusters. These gene clusters of various sizes correspond predominantly to low recombination genomic regions such as inversions and centromeres, and also to recent selective sweeps. Because this mosquito species complex has been studied extensively, we were able to support our interpretations with previously published findings. Several novel observations and hypotheses are also made, including selective sweeps and a multi-locus selection event in Guinea-Bissau, a known intense hybridization zone between An. gambiae and An. coluzzii. Conclusions Our results present a rich dataset that could be utilized in functional investigations aiming to shed light onto An. gambiae s.l genome evolution and eventual speciation. In addition, the methodology presented here can be used to further characterize other species not so well studied as An. gambiae, shortening the time required to progress from field sampling to the identification of genes and genomic regions under unique evolutionary processes.

Islands possess physical characteristics that make them uniquely well-suited for initial field trials of new genetic-based technologies applied to African malaria vectors. This has led to efforts to characterize the degree of isolation of island mosquito populations. São Tomé and Príncipe (STP) is a country composed of two small islands in the Gulf of Guinea (Central Africa) where Anopheles coluzzii is the primary malaria vector. Several studies have shown a relatively high degree of genetic isolation between A. coluzzii populations in STP and the mainland compared with pairs of mainland populations separated by equivalent distances. Here, we analyzed complete mitochondrial genomes of individual A. coluzzii specimens from STP and neighboring mainland countries. The objectives are to describe the history of A. coluzzii establishment in STP, specifically to address several questions germane to their suitability as sites for a field trial release of genetically engineered mosquitoes (GEMs). These questions include: (i) What are the origins of A. coluzzii populations in STP?; (ii) How many introductions occurred?; (iii) When was A. coluzzii introduced into STP? and (iv) Is there ongoing, contemporary gene flow into STP from mainland populations? Phylogenetic analysis and haplotype networks were constructed from sequences of 345 A. coluzzii from STP, and 107 individuals from 10 countries on or near the west coast of Africa. Analysis of these data suggest that there have been two introductions of A. coluzzii onto the island of São Tomé that occurred roughly 500 years ago and that these originated from mainland West Africa. It appears that A. coluzzii has never been introduced into Príncipe Island directly from mainland Africa, but there have been at least four introductions originating from São Tomé. Our findings provide further support for the notion that contemporary populations of A. coluzzii on São Tomé and Príncipe are genetically isolated from mainland populations of this mosquito species.

Novel malaria control strategies using genetically engineered mosquitoes (GEMs) are on the horizon. Population modification is one approach wherein mosquitoes are engineered with genes rendering them refractory to the malaria parasite, Plasmodium falciparum, coupled with a low‐threshold, Cas9‐based gene drive. When released into a wild vector population, GEMs preferentially transmit these parasite‐blocking genes to their offspring, ultimately modifying a vector population into a nonvector one. Deploying this technology awaits ecologically contained field trial evaluations. Here, we consider a process for site selection, the first critical step in designing a trial. Our goal is to identify a site that maximizes prospects for success, minimizes risk, and serves as a fair, valid, and convincing test of efficacy and impacts of a GEM product intended for large‐scale deployment in Africa. We base site selection on geographic, geological, and biological, rather than social or legal, criteria. We recognize the latter as critically important but not as a first step in selecting a site. We propose physical islands as being the best candidates for a GEM field trial and present an evaluation of 22 African islands. We consider geographic and genetic isolation, biological complexity, island size, and topography and identify two island groups that satisfy key criteria for ideal GEM field trial sites.

Established populations of Aedes aegypti, a mosquito vector of multiple major arthropod-borne viruses, were first found in three California (CA) cities in 2013. From 2013 to April 2021, Ae. aegypti thwarted almost all control efforts to stop its spread and expanded its range to 308 cities, including Exeter, in 22 counties in CA. Population genomic analyses have suggested that multiple genetically distinct Ae. aegypti populations were introduced into CA. However Ae. aegypti collected for the first time in 2014 in Exeter, appeared to be different from three major genetic clusters found elsewhere in CA. Due to intense control efforts by the Delta Vector Control District (DVCD), Ae. aegypti was thought to have been eliminated from Exeter in 2015. Unfortunately, it was recollected in 2018. It was not clear if the reemergence of Ae. aegypti in Exeter was derived from the bottlenecked remnants of the original 2014 Exeter population or from an independent invasion from a different population derived from surrounding areas. The goal of this work was to determine which of these scenarios occurred (recovery after bottleneck or reintroduction after elimination) and if elimination and reintroduction occurred to identify the origin of the invading population using a population genomic approach. Our results support the reintroduction after elimination hypothesis. The source of reintroduction, however, was unexpectedly from the southern CA cluster rather than from other two geographically closer central CA genetic clusters. We also conducted a knockdown resistance mutation profile, which showed Exeter 2014 had the lowest level of resistant alleles compared to the other populations, could have contributed towards DVCD’s ability to locally eliminate Ae. aegypti in 2014.

Made available in DSpace on 2020-12-12T02:28:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-12-01 Aedes aegypti is the most synanthropic and anthropophilic mosquito of Culicidae. This species always cohabits with humans and is extremely opportunistic. Vector dispersal is directly related to the ability of the females on successfully finding a mate in a generally patchy urban scenario. In the present work, we investigate transcriptional changes in Ae. aegypti females during the courtship process and after mating. We observe a substantial alteration in gene expression triggered just upon contact with Ae. aegypti males, which in turn was not fully correlated to the changes triggered by the contact. After analysing shared significant differentially regulated genes between conspecific contact and insemination, the major part of the observed transcriptomic change triggered by contact is reversed after mating, indicating an intermediary situation between naive and mating conditions that we hypothesize to be crucial for mating success. Upon contact, several chemosensory related genes are repressed, especially odorant binding proteins. Most of these genes return to higher expression rates after mating. None of these genes are significantly regulated by the encounter of a different species, Aedes albopictus. The results presented here might be applied to an innovative control approach focusing on the semiochemical systems of mosquitoes in an effort to disrupt undesirable host–insect interaction to reduce the risk of pathogen transmission to humans. Sao Paulo State University – UNESP Biotechnology Institute and Bioscience Institute Keele University Centre for Applied Entomology and Parasitology Sao Paulo State University – UNESP Biotechnology Institute and Bioscience Institute

Anopheles coluzzii is a major malaria vector throughout its distribution in west-central Africa. Here we present a whole-genome study of 142 specimens from nine countries in continental Africa and three islands in the Gulf of Guinea. This sample set covers a large part of this species’ geographic range. Our population genomic analyses included a description of the structure of mainland populations, island populations, and connectivity between them. Three genetic clusters are identified among mainland populations and genetic distances (FST) fits an isolation-by-distance model. Genomic analyses are applied to estimate the demographic history and ancestry for each island. Taken together with the unique biogeography and history of human occupation for each island, they present a coherent explanation underlying levels of genetic isolation between mainland and island populations. We discuss the relationship of our findings to the suitability of São Tomé and Príncipe islands as candidate sites for potential field trials of genetic-based malaria control strategies., Campos, Lanzaro and colleagues use whole-genome sequencing and population genomic analyses to infer connectivity between mainland and island mosquito populations in West Africa. The unique biogeographic history for each island population is reported, and the findings highlight potential candidate sites for genetic-based malaria control strategies.

We report the first complete mitogenome (Mt) sequence of Anopheles coustani, an understudied malaria vector in Africa. The sequence was extracted from one individual mosquito from São Tomé island. The length of the A. coustani Mt genome was 15,408 bp with 79.3% AT content. Phylogenetic analysis revealed that A. coustani is most closely related to A. sinensis (93.5% of identity); and 90.1% identical to A. gambiae complex members. publishersversion published

Anopheles coluzzii is a major malaria vector throughout its distribution in west-central Africa. Here we present a whole-genome resequencing study of 77 specimens from eight localities, that covers a large part of this species’ range, including three islands in the Gulf of Guinea: Bioko, Sao Tome and Principe. Population genomic analyses encompassed structure of mainland populations, of island populations and connectivity between island and mainland populations. Three genetic clusters were found among mainland populations and genetic distances among all populations fit an isolation-by-distance model. Genomic analyses were applied to estimating the demographic history and ancestry (cross-coalescence) for each island. Taken together with the unique biogeography and history of human occupation for each island they present a coherent explanation underlying contemporary levels of genetic isolation between mainland and island populations and among island populations. We discuss the relation of our findings to the suitability of Sao Tome and Principe islands as candidate sites for potential field trials of genetic-based malaria control strategies.

Made available in DSpace on 2019-10-06T17:09:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-17 Background: In the Amazon Basin, Nyssorhynchus (Anopheles) darlingi is the most aggressive and effective malaria vector. In endemic areas, behavioral aspects of anopheline vectors such as host preference, biting time and resting location post blood meal have a key impact on malaria transmission dynamics and vector control interventions. Nyssorhynchus darlingi presents a range of feeding and resting behaviors throughout its broad distribution. Methods: To investigate the genetic diversity related to biting behavior, we collected host-seeking Ny. darlingi in two settlement types in Acre, Brazil: Granada (~ 20-year-old, more established, better access by road, few malaria cases) and Remansinho (~ 8-year-old, active logging, poor road access, high numbers malaria cases). Mosquitoes were classified by the location of collection (indoors or outdoors) and time (dusk or dawn). Results: Genome-wide SNPs, used to assess the degree of genetic divergence and population structure, identified non-random distributions of individuals in the PCA for both location and time analyses. Although genetic diversity related to behavior was confirmed by non-model-based analyses and F ST values, model-based STRUCTURE detected considerable admixture of these populations. Conclusions: To our knowledge, this is the first study to detect genetic markers associated with biting behavior in Ny. darlingi. Additional ecological and genomic studies may help to understand the genetic basis of mosquito behavior and address appropriate surveillance and vector control. Biotechnology Institute (IBTEC) Biosciences Institute at Botucatu (IBB) Sao Paulo State University (UNESP) Department of Biomedical Sciences School of Public Health University at Albany (State University of New York) Wadsworth Center New York State Department of Health Division of Infectious Diseases Department of Medicine University of California San Diego Laboratorio de Investigación y Desarrollo Departamento de Ciencias Celulares y Moleculares Instituto de Medicina Tropical Alexander von Humboldt Universidad Peruana Cayetano Heredia Biology Department St. Mary's College of Maryland Biotechnology Institute (IBTEC) Biosciences Institute at Botucatu (IBB) Sao Paulo State University (UNESP)

In the Amazon Basin, Anopheles (Nyssorhynchus) darlingi is the most aggressive and effective malaria vector. In endemic areas, behavioral aspects of anopheline species such as host preference, biting time and resting location after a blood meal have a key impact on malaria transmission dynamics and transmission control strategies. An. darlingi present a variety in behavior throughout its broad distribution including blood feeding related. To investigate the genetic basis of its biting behaviors, host-seeking An. darlingi were collected in two settlements (Granada and Remansinho) in Acre, Brazil. Mosquitoes were classified by captured location (indoors or outdoors) and time (dusk or dawn). Genome-wide SNPs were used to assess the degree of genetic diversity and structure in these groups. There was evidence of genetic component of biting behavior regarding both location and time in this species. This study supports that An. darlingi blood-feeding behavior has a genetic component. Additional ecological and genomic studies may help to understand the genetic basis of mosquito behavior and address appropriate surveillance and vector control.Author SummaryMalaria is a disease caused by parasite of the genus Plasmodium and is transmitted by mosquitoes of the genus Anopheles. In the Amazon Basin, the main malaria vector is Anopheles darlingi, which is present in high densities in this region. Egg development requires that females of this mosquito seek hosts for blood meals. Anopheles females blood feeding may occur indoor or outdoor the houses and typically from the sunset to dawn. Anopheles darlingi in particular present great variability regarding its behaviour, presenting variety of peak biting times and patterns. This work shows that there is a genetic component that partially explains these two behaviors: location of the blood meal (inside or outside the houses) and time of feeding. Single nucleotide polymorphisms (SNPs) scattered throughout the genome of Anopheles darlingi showed genetic diversity and structure in these groups. A comprehensive understanding of the genetic basis for mosquito behaviour may support innovative vector surveillance and control strategies.

This study aims to investigate whether foreign direct investment (FDI) growth improved the Brazilian foreign trade in the long run and whether there is a predictable relationship between a firm's FDI strategy and a firm's foreign trade. We applied moderated multiple regressions and generalized linear models to test the effects of FDI on both export and import equations of 11 Brazilian industries from 1996 to 2009. Our data sources include the Ministry of Development, Industry and Foreign Trade Ministry, Central Bank of Brazil, and the Applied Research Institute. Results showed that FDI is correlated with increased exports in the short run, but not in the long run. In the long run, the positive relationship between FDI and exports will only occur for export-oriented industries in which resource-seeking strategies are preponderant. We found a positive relationship between imports and FDI in the short run, particularly in import-oriented industries. A negative relationship between FDI and imports was found i...

Introdução: As rezadeiras exercem o seu papel de cura por meios simbólicos e agem principalmente sobre enfermidades de pouca gravidade. Objetivo: Conhecer as ressignificações no processo do cuidado a partir das práticas das rezadeiras no Projeto Quatro Varas. Metodologia: Pesquisa de campo com abordagem qualitativa, realizada no período de agosto de 2016 até julho de 2017, no Projeto Quatro Varas em Fortaleza. Para coleta de dados fizemos entrevistas com 6 informantes que utilizavam as práticas de reza. Os dados coletados foram interpretados a partir da análise de narrativa e da Antropologia Interpretativa. A pesquisa teve aprovação do Comitê de Ética e Pesquisa do IPADE, com número de aprovação 55697416.0.0000.5049. Resultados: Evidenciamos nas narrativas dos entrevistados que após procurar a rezadeira sentiram-se melhor e acreditam no poder de cura dessas mulheres que ofertam saúde para a comunidade de forma gratuita e de fácil acesso como vemos a seguir: “eu fico logo bem. Só procuro quando não tô bem, eu sei que aquele momento ela vai me tocar, ela vai depositar aquela energia positiva dela na minha pessoa, no momento eu já fico bem”; (Orquidea); “Me sentia bem, porque eu sabia que estava buscando um bem para meu filho e se eu fosse procurar ela era porque eu acreditava. Me sentia confortável e deu certo até hoje” (Margarida). Conclusão: Essa prática cultural, apesar de ser muito procurada no passado, por sua eficácia de promover bem-estar, vem sendo esquecida com o passar dos anos, mas influencia até hoje diretamente nas crenças e conhecimentos populares.

Made available in DSpace on 2018-12-11T17:31:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-02-13 Background: In recent decades, throughout the Amazon Basin, landscape modification contributing to profound ecological change has proceeded at an unprecedented rate. Deforestation that accompanies human activities can significantly change aspects of anopheline biology, though this may be site-specific. Such local changes in anopheline biology could have a great impact on malaria transmission. The aim of this study was to investigate population genetics of the main malaria vector in Brazil, Anopheles darlingi, from a microgeographical perspective. Methods: Microsatellites and ddRADseq-derived single nucleotide polymorphisms (SNPs) were used to assess levels of population genetic structuring among mosquito populations from two ecologically distinctive agricultural settlements (~60 km apart) and a population from a distant (~700 km) urban setting in the western Amazon region of Brazil. Results: Significant microgeographical population differentiation was observed among Anopheles darlingi populations via both model- and non-model-based analysis only with the SNP dataset. Microsatellites detected moderate differentiation at the greatest distances, but were unable to differentiate populations from the two agricultural settlements. Both markers showed low polymorphism levels in the most human impacted sites. Conclusions: At a microgeographical scale, signatures of genetic heterogeneity and population divergence were evident in Anopheles darlingi, possibly related to local environmental anthropic modification. This divergence was observed only when using high coverage SNP markers. Biotechnology Institute (IBTEC) and Biosciences Institute at Botucatu (IBB) Sao Paulo State University (UNESP) Department of Biomedical Sciences School of Public Health University at Albany State University of New York New York State Department of Health Wadsworth Center Division of Infectious Diseases Department of Medicine University of California San Diego Instituto de Medicina Tropical Alexander von Humboldt, Departamento de Ciencias Celulares y Moleculares Laboratorio de Investigación y Desarrollo Universidad Peruana Cayetano Heredia Biology Department St. Mary's College of Maryland Biotechnology Institute (IBTEC) and Biosciences Institute at Botucatu (IBB) Sao Paulo State University (UNESP)

Este estudo teve como objetivo investigar se, e em quais situações a presença estrangeira pode espalhar ou transbordar uma vantagem para a economia local. Os dados foram analisados por meio de Modelos Lineares Generalizados de Medidas Repetidas associando os efeitos do tipo de capital controlador e as diferentes regiões brasileiras sobre variáveis selecionadas. Adicionalmente, foram desenvolvidas análises modelos GLM buscando identificar os efeitos de transbordamentos da presença estrangeira com base em uma função de produção. Não há evidências de que o tipo de capital controlador exerça influência significativa sobre a ocorrência de transbordamentos. A região em que estrangeiros se estabelecem é um fator relevante na análise de transbordamentos.

Made available in DSpace on 2014-09-30T18:18:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2013Bitstream added on 2014-10-01T14:04:14Z : No. of bitstreams: 1 S0074-02762013000900003.pdf: 529161 bytes, checksum: 81385c72bbd25c5d11a271d286f7317a (MD5) The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal) resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA) genes [cytochrome oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4)] and knockdown resistance ( kdr ) mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosquito populations from Brazil and Venezuela in the analysis as putative geographic sources. The Ae. aegyptipopulation from Madeira showed extremely low mtDNA genetic variability, with a single haplotype for COI and ND4. We also detected the presence of two important kdr mutations and the quasi-fixation of one of these mutations (F1534C). These results are consistent with a unique recent founder event that occurred on the island of Ae. aegyptimosquitoes that carry kdr mutations associated with insecticide resistance. Finally, we also report the presence of the F1534C kdr mutation in the Brazil and Venezuela populations. To our knowledge, this is the first time this mutation has been found in South American Ae. aegypti mosquitoes. Given the present risk of Ae. aegypti re-invading continental Europe from Madeira and the recent dengue outbreaks on the island, this information is important to plan surveillance and control measures. Unidade de Ensino e Investigacao-Parasitologia Medica Centro de Malaria e outras Doencas Tropicais Universidade Nova de Lisboa Instituto de Higiene e Medicina Tropical Unidade de Parasitologia e Microbiologia Medicas Instituto de Administracao da Saude e Assuntos Sociais Unidade de Engenharia Sanitaria Departamento de Promocao e Protecao da Saude Universidade Estadual Paulista Instituto de Biociencias Departamento de Parasitologia Universidad Central de Venezuela Instituto de Medicina Tropical Seccion Entomologia Medica Universidade Estadual Paulista Instituto de Biociencias Departamento de Parasitologia

Made available in DSpace on 2013-09-27T14:54:32Z (GMT). No. of bitstreams: 1 WOS000312452400014.pdf: 1589838 bytes, checksum: 384bb9b09756bbc40b0fcc256cad2a94 (MD5) Previous issue date: 2012-11-01 Made available in DSpace on 2013-09-30T18:40:01Z (GMT). No. of bitstreams: 1 WOS000312452400014.pdf: 1589838 bytes, checksum: 384bb9b09756bbc40b0fcc256cad2a94 (MD5) Previous issue date: 2012-11-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:52:36Z No. of bitstreams: 1 WOS000312452400014.pdf: 1589838 bytes, checksum: 384bb9b09756bbc40b0fcc256cad2a94 (MD5) Made available in DSpace on 2014-05-20T13:52:36Z (GMT). No. of bitstreams: 1 WOS000312452400014.pdf: 1589838 bytes, checksum: 384bb9b09756bbc40b0fcc256cad2a94 (MD5) Previous issue date: 2012-11-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Population genetic studies of insect vectors can generate knowledge to improve epidemiological studies focused on the decrease of pathogen transmission. In this study, we used nine SNPs across the Aedes aegypti genome to characterize seasonal population variations of this important dengue vector. Mosquito samples were obtained by ovitraps placed over Botucatu SP from 2005 to 2010. Our data show that, regardless of the large variation in mosquito abundance (deduced from the number of eggs obtained from ovitraps), the effective population size remained stable over the years. These results suggest that Ae. aegypti is able to maintain a sufficiently large active breeding population during the dry season to keep genetic frequencies stable. These results open new perspectives on mosquito survey and control methods. Univ Estadual Paulista, Dept Parasitol, Inst Biociencias, São Paulo, Brazil SUCEN, São Paulo, Brazil Univ Nova Lisboa, UEI Parasitol Med, Ctr Malaria & Outras Doencas Tropicais, Inst Higiene & Med Trop, P-1200 Lisbon, Portugal Univ Estadual Paulista, Dept Parasitol, Inst Biociencias, São Paulo, Brazil

Towards a Sustainable and Efficient State: The Development Agenda of Belize represents a tangible expression of the Inter-American Development Bank's commitment to generating knowledge as part of its assistance to its borrowing member countries and illustrates the Bank's willingness to accompany Belize in its efforts to overcome its development challenges. This intellectual contribution to some of the most important issues regarding Belize's economic and social development is directed primarily at two audiences. First, it is directed at Belizean policymakers, offering a technical and internationally comparative perspective. Second, it is aimed at the wider public who are interested in Belize's economic and social development but who find little material available on the subject.