Revision of the Strodei Subgroup of Nyssorhynchus (Diptera: Culicidae), with descriptions of 2 new species.

Nyssorhynchus (Nyssorhynchus) ibiapabaensis (Sant'Ana & Sallum n. sp.) and Ny. (Nys.) untii (Sant'Ana & Sallum n. sp.) are new species of the Arthuri Complex of the Strodei Subgroup. The new species are described and validated using morphological characters of the male, female, and immature stages. The description of the male, female, fourth-instar larva and pupa of Ny. arthuri (Unti, 1941) and Ny. albertoi (Unti, 1941) are provided for the first time. To avoid nomenclature instability, neotypes are designated for both species. All life stages of Ny. strodei (Root, 1926) employing specimens collected in the Agua Limpa District, Juiz de Fora, Minas Gerais, Brazil are redescribed.

Bacterial diversity on larval and female Mansonia spp. from different localities of Porto Velho, Rondonia, Brazil.

Studies based on the bacterial diversity present in Mansonia spp. are limited; therefore, the aim of this study was to investigate the bacterial diversity in females and larvae of Mansonia spp., describe the differences between the groups identified, and compare the microbiota of larvae from different collection sites. Sequences of the 16S rRNA region from the larvae and females of Mansonia spp. were analyzed. Diversity analyzes were performed to verify the possible bacterial differences between the groups and the collection sites. The results showed Pseudomonas was the most abundant genus in both females and larvae, followed by Wolbachia in females and Rikenellaceae and Desulfovibrio in larvae. Desulfovibrio and Sulfurospirillum, sulfate- and sulfur-reducing bacteria, respectively, were abundant on the larvae. Aminomonas, an amino acid-degrading bacterium, was found only in larvae, whereas Rickettsia was identified in females. Bacterial diversity was observed between females and larvae of Mansonia and between larvae from different collection sites. In addition, the results suggest that the environment influenced bacterial diversity.

Mutations Linked to Insecticide Resistance Not Detected in the Ace-1 or VGSC Genes in Nyssorhynchus darlingi from Multiple Localities in Amazonian Brazil and Peru.

Indoor residual spray (IRS), mainly employing pyrethroid insecticides, is the most common intervention for preventing malaria transmission in many regions of Latin America; the use of long-lasting insecticidal nets (LLINs) has been more limited. Knockdown resistance (kdr) is a well-characterized target-site resistance mechanism associated with pyrethroid and DDT resistance. Most mutations detected in acetylcholinesterase-1 (Ace-1) and voltage-gated sodium channel (VGSC) genes are non-synonymous, resulting in a change in amino acid, leading to the non-binding of the insecticide. In the present study, we analyzed target-site resistance in Nyssorhynchus darlingi, the primary malaria vector in the Amazon, in multiple malaria endemic localities. We screened 988 wild-caught specimens of Ny. darlingi from three localities in Amazonian Peru and four in Amazonian Brazil. Collections were conducted between 2014 and 2021. The criteria were Amazonian localities with a recent history as malaria hotspots, primary transmission by Ny. darlingi, and the use of both IRS and LLINs as interventions. Fragments of Ace-1 (456 bp) and VGSC (228 bp) were amplified, sequenced, and aligned with Ny. darlingi sequences available in GenBank. We detected only synonymous mutations in the frequently reported Ace-1 codon 280 known to confer resistance to organophosphates and carbamates, but detected three non-synonymous mutations in other regions of the gene. Similarly, no mutations linked to insecticide resistance were detected in the frequently reported codon (995) at the S6 segment of domain II of VGSC. The lack of genotypic detection of insecticide resistance mutations by sequencing the Ace-1 and VGSC genes from multiple Ny. darlingi populations in Brazil and Peru could be associated with low-intensity resistance, or possibly the main resistance mechanism is metabolic.

Entomological Reference Collection: 85 years of contributions to public health.

The Department of Hygiene of the Faculty of Medicine of São Paulo (FMUSP), organized with the support of the Rockefeller Foundation, became the Institute of Hygiene, with the inaugural class taught by Samuel Darling in 1918. The history of Public Health Entomology is mixed with that of the Institute itself, which became the Faculty of Hygiene and Public Health in 1945. Still in the 1930s, Paulo César de Azevedo Antunes and John Lane organized Public Health Entomology within the Medical Parasitology area of the then Institute of Hygiene. During this period, the entomology laboratory came to be recognized for its research in the systematics of hematophagous insects, as well as in the ecology, biology and behavior of vectors. The Entomological Reference Collection (CER) originated naturally from the research of Paulo César Antunes and John Lane and is a national and international heritage covering primary and secondary types of insect species that are of interest to public health. Over the years, it has been consolidated with the efforts of Augusto Ayroza Galvão, Renato Corrêa, José Coutinho, Nelson Cerqueira, Ernesto Rabello, Oswaldo Forattini and others. In its over eighty years of activities, CER has enabled the training of several scientists able to act in programs of surveillance and control of endemic diseases associated with insect vectors throughout Latin America, in addition to training taxonomists focused on insects of interest in Public Health. Researchers from other Brazilian institutes and abroad joined the entomology laboratory because of its importance and the research developed in it. The growing scientific production made it possible for entomological studies developed at the Faculty of Public Health (FSP) to gain international visibility, contributing to the development of disease prevention and epidemic control actions in the country.

DNA Barcodes of Mansonia (Mansonia) Blanchard, 1901 (Diptera, Culicidae).

Females of the genus Mansonia feed on the blood of humans, livestock, and other vertebrates to develop their eggs. The females' biting behavior may cause severe disturbance to blood hosts, with a negative impact on public health and economics. Certain species have been identified as potential or effective disease vectors. The accurate species identification of field-collected specimens is of paramount importance for the success of monitoring and control strategies. Mansonia (Mansonia) morphological species boundaries are blurred by patterns of intraspecific heteromorphism and interspecific isomorphism. DNA barcodes can help to solve taxonomic controversies, especially if combined with other molecular tools. We used cytochrome c oxidase subunit I (COI) gene 5' end (DNA barcode) sequences to identify 327 field-collected specimens of Mansonia (Mansonia) spp. The sampling encompassed males and females collected from three Brazilian regions and previously assigned to species based on their morphological characteristics. Eleven GenBank and BOLD sequences were added to the DNA barcode analyses. Initial morphospecies assignments were mostly corroborated by the results of five clustering methods based on Kimura two-parameter distance and maximum likelihood phylogeny. Five to eight molecular operational taxonomic units may represent taxonomically unknown species. The first DNA barcode records for Mansonia fonsecai, Mansonia iguassuensis, and Mansonia pseudotitillans are presented.

Host Feeding Patterns of Mansonia (Diptera, Culicidae) in Rural Settlements near Porto Velho, State of Rondonia, Brazil.

Mosquito females of the genus Mansonia (Blanchard) can be a nuisance to humans and animals since they are voraciously hematophagous and feed on the blood of a variety of vertebrates. Despite their relevance, there is a lack of investigation into the blood-feeding patterns of the Mansonia species. Knowledge of the host preference is crucial in establishing the public health importance of a mosquito species and its potential to be involved in the transmission dynamics of pathogens. Species that are primarily anthropophilic can be more effective in spreading vector-borne pathogens to humans. In this study, we used an Illumina Nextera sequencing protocol and the QIIME2 workflow to assess the diversity of DNA sequences extracted in the ingested blood of mosquito species to evaluate the overall and local host choices for three species: Ma. titillans, Ma. Amazonensis, and Ma. humeralis, in rural areas alongside the Madeira River in the vicinities of the Santo Antonio Energia (SAE) reservoir in the municipality of Porto Velho, Rondônia, Western Brazil. By performing our analysis pipeline, we have found that host diversity per collection site showed a significant heterogeneity across the sample sites. In addition, in rural areas, Ma. amazonensis present a high affinity for B. taurus, Ma. humeralis shows an overall preference for C. familiaris and B. taurus, but also H. sapiens and E. caballus in urban areas, and Ma. titillans showed more opportunistic behavior in rural areas, feeding on wild animals and G. gallus, though with an overall preference for H. sapiens.

The SISBIOTA-Diptera Brazilian Network: A long-term survey of Diptera from unexplored Brazilian Western Arc of Amazon, Cerrado, and Pantanal

ABSTRACT The SISBIOTA-BRASIL was a three-year multimillion-dollar research program of the Brazilian government to document plants and animals in endangered/understudied areas and biomes in Brazil. Distributional patterns and the historical events that generated them are extensively unknown regarding Brazilian fauna and flora. This deficiency hinders the development of conservation policies and the understanding of evolutionary processes. Conservation decisions depend on precise knowledge of the taxonomy and geographic distribution of species. Given such a premise, we proposed to research the diversity of Diptera of the Brazilian western arc of Amazon, Cerrado, and Pantanal in the states of Mato Grosso, Mato Grosso do Sul, and Rondônia. Three important biomes of the South American continent characterize these Brazilian states: Amazon forest, Cerrado (Brazilian Savannah), and Pantanal. Besides their ecological relevance, these biomes historically lack intensive entomological surveys. Therefore, they are much underrepresented in the Brazilian natural history collections and in the scientific literature, which is further aggravated by the fact that these areas are being exponentially and rapidly converted to commercial lands. Our project involved over 90 collaborators from 24 different Brazilian institutions and one from Colombia among researchers, postdocs, graduate and undergraduate students, and technicians. We processed and analyzed nearly 300,000 specimens from ~60 families of Diptera collected with a large variety of methods in the sampled areas. Here, we provide a detailed overview of the genera and species diversity of 41 families treated. Our results point to a total of 2,130 species and 514 genera compiled and identified for the three states altogether, with an increase of 41% and 29% in the numbers of species and genera known for the three states combined, respectively. Overall, the 10 most species-rich families were Tachinidae, Cecidomyiidae, Tabanidae, Psychodidae, Sarcophagidae, Stratiomyidae, Bombyliidae, Syrphidae, Tephritidae, and Asilidae. The 10 most diverse in the number of genera were Tachinidae, Stratiomyidae, Asilidae, Mycetophilidae, Syrphidae, Tabanidae, Muscidae, Dolichopodidae, Sarcophagidae, and Chloropidae. So far, 111 scientific papers were published regarding taxonomic, phylogenetic, and biogeographical aspects of the studied families, with the description of 101 new species and three new genera. We expect that additional publications will result from this investigation because several specimens are now curated and being researched by specialists.

Entomological Reference Collection: 85 years of contributions to public health / Coleção Entomológica de Referência: 85 anos de contribuições à saúde pública

ABSTRACT The Department of Hygiene of the Faculty of Medicine of São Paulo (FMUSP), organized with the support of the Rockefeller Foundation, became the Institute of Hygiene, with the inaugural class taught by Samuel Darling in 1918. The history of Public Health Entomology is mixed with that of the Institute itself, which became the Faculty of Hygiene and Public Health in 1945. Still in the 1930s, Paulo César de Azevedo Antunes and John Lane organized Public Health Entomology within the Medical Parasitology area of the then Institute of Hygiene. During this period, the entomology laboratory came to be recognized for its research in the systematics of hematophagous insects, as well as in the ecology, biology and behavior of vectors. The Entomological Reference Collection (CER) originated naturally from the research of Paulo César Antunes and John Lane and is a national and international heritage covering primary and secondary types of insect species that are of interest to public health. Over the years, it has been consolidated with the efforts of Augusto Ayroza Galvão, Renato Corrêa, José Coutinho, Nelson Cerqueira, Ernesto Rabello, Oswaldo Forattini and others. In its over eighty years of activities, CER has enabled the training of several scientists able to act in programs of surveillance and control of endemic diseases associated with insect vectors throughout Latin America, in addition to training taxonomists focused on insects of interest in Public Health. Researchers from other Brazilian institutes and abroad joined the entomology laboratory because of its importance and the research developed in it. The growing scientific production made it possible for entomological studies developed at the Faculty of Public Health (FSP) to gain international visibility, contributing to the development of disease prevention and epidemic control actions in the country.

RESUMO O Departamento de Higiene da Faculdade de Medicina de São Paulo (FMUSP), organizado com o apoio da Fundação Rockefeller, tornou-se o Instituto de Higiene, tendo a aula inaugural ministrada por Samuel Darling em 1918. A história da Entomologia de Saúde Pública confunde-se com a do próprio Instituto, que passou a ser a Faculdade de Higiene e Saúde Pública em 1945. Ainda na década de 1930, Paulo César de Azevedo Antunes e John Lane começam a organizar a Entomologia de Saúde Pública dentro da Parasitologia Médica, do então Instituto de Higiene. Durante esse período o laboratório de entomologia passou a ser reconhecido por suas pesquisas em sistemática de insetos hematófagos, bem como na ecologia, biologia e comportamento de vetores. A Coleção Entomológica de Referência (CER) originou-se naturalmente das pesquisas de Paulo César Antunes e John Lane e é um patrimônio nacional e internacional abrangendo tipos primários e secundários de espécies de insetos que apresentam interesse à saúde pública. No decorrer dos anos, consolidou-se com os esforços de Augusto Ayroza Galvão, Renato Corrêa, José Coutinho, Nelson Cerqueira, Ernesto Rabello, Oswaldo Forattini e outros. Em seus mais de oitenta anos de atividades, a CER possibilitou a formação de diversos cientistas aptos a atuar em programas de vigilância e controle de endemias associadas aos insetos vetores em toda a América Latina, além de formar taxonomistas voltados aos insetos de interesse em Saúde Pública. Pesquisadores de outros institutos brasileiros e do exterior juntaram-se ao laboratório de entomologia por conta de sua importância e das pesquisas nele desenvolvidas. A produção científica crescente possibilitou aos estudos entomológicos desenvolvidos na Faculdade de Saúde Pública (FSP) adquirirem uma visibilidade internacional, contribuindo para o desenvolvimento das ações de prevenções de doenças e controle de epidemias no país.

A new species of the Arthuri Complex of the Strodei Subgroup of Nyssorhynchus (Diptera: Culicidae).

Nyssorhynchus (Nyssorhynchus) rondoniensis, a new species of the Arthuri Complex of the Strodei Subgroup, is described and validated using morphological characters of the adult male and female, male genitalia, fourth-instar larva and pupa. The new species is recorded in the municipalities of Campo Novo de Rondnia and Monte Negro, Rondnia State, Brazil. Based on DNA sequence data, the new species (as Ny. arthuri species C) was found to belong to a separate lineage within the Arthuri Complex. Morphological characteristics of the male genitalia and fourth-instar larva confirmed that the new species shared morphological similarities with other species of the Arthuri Complex, but it can be distinguished by characteristics of the male genitalia, adult female and larva. Nyssorhynchus rondoniensis may be involved in malaria transmission because females can be easily misidentified as Ny. oswaldoi (Peryass, 1922) s.l. or Ny. konderi (Galvo Damasceno, 1942) s.l. Both species were previously hypothesized to be local vectors in Acre and Rondnia States.

A new species of the Nuneztovari Complex of Nyssorhynchus (Diptera: Culicidae) from the western Brazilian Amazon.

Nyssorhynchus (Nyssorhynchus) jamariensis, a new species of the Nuneztovari Complex, previously known as Anopheles (Nyssorhynchus) nuneztovari A, is described and validated using morphological characters of the adult male and female, male genitalia and immature stages. The species is recorded from the western Brazilian Amazon, where it was collected in pastures in the vicinity of the Jamari River, municipality of Monte Negro, Rondnia State, Brazil. Illustrations of the male genitalia, fourth-instar larva and pupa are provided. Nyssorhynchus jamariensis may be involved in malaria transmission, but its vector status needs further investigation.

Culex chrysothorax (Newstead amp; Thomas, 1910) (Diptera: Culicidae), preoccupied by Cx. chrysothorax (Peryass, 1908) and recognized as a subjective synonym of Cx. trigeminatus Clastrier, 1970.

Culex chrysothorax (Newstead Thomas, 1910) (Diptera: Culicidae) is recognized as the junior secondary homonym of Culex chrysothorax (Peryass, 1908). Both nominal species are currently regarded as nomina dubia (Pecor et al. 1991; Harbach 2018; Wilkerson et al. 2021). Based on critical examination of the lectotype female, the former nominal species, which was treated as species inquirenda by Forattini Sallum (1989), is no longer regarded as a doubtful species, and is found to be conspecific with Cx. trigeminatus Clastrier, 1970. Because it is preoccupied by Cx. chrysothorax (Peryass, 1908), it is placed in synonymy with Cx. trigeminatus, which is transferred from the Educator to the Atratus Group of the subgenus Melanoconion based on morphological features of the female. Culex chrysothorax (Peryass, 1908) is retained in the Educator Group as a nomen dubium. Because the original description of Cx. chrysothorax (Newstead Thomas) likely included misidentified specimens of Cx. theobaldi (Lutz, 1904), a more precise description of the lectotype female is provided.

Mansonia spp. population genetics based on mitochondrion whole-genome sequencing alongside the Madeira River near Porto Velho, Rondonia, Brazil.

In high abundance, females of the genus Mansonia (Blanchard) can be a nuisance to humans and animals because they are voraciously hematophagous and feed on the blood of a myriad of vertebrates. The spatial-temporal distribution pattern of Mansonia species is associated with the presence of their host plants, usually Eichhornia crassipes, E. azurea, Ceratopteris pteridoides, Limnobium laevigatum, Pistia stratiotes, and Salvinia sp. Despite their importance, there is a lack of investigation on the dispersion and population genetics of Mansonia species. Such studies are pivotal to evaluating the genetic structuring, which ultimately reflects populational expansion-retraction patterns and dispersal dynamics of the mosquito, particularly in areas with a history of recent introduction and establishment. The knowledge obtained could lead to better understanding of how anthropogenic changes to the environment can modulate the population structure of Mansonia species, which in turn impacts mosquito population density, disturbance to humans and domestic animals, and putative vector-borne disease transmission patterns. In this study, we present an Illumina NGS sequencing protocol to obtain whole-mitogenome sequences of Mansonia spp. to assess the microgeographic genetic diversity and dispersion of field-collected adults. The specimens were collected in rural environments in the vicinities of the Santo Antônio Energia (SAE) hydroelectric reservoir on the Madeira River.

Revision of the Educator Group of Culex (Melanoconion) (Diptera, Culicidae).

The Educator Group of the Melanoconion Section of Culex (Melanoconion) (Diptera, Culicidae) is reviewed. Currently, the group includes the following valid species: Culex (Melanoconion) aphyllusTalaga, 2020, Culex (Melanoconion) cristovaoi Duret, 1968, Culex (Melanoconion) educatorDyar & Knab, 1906, Culex (Melanoconion) eknomiosForattini & Sallum, 1992, Culex (Melanoconion) inadmirabilisDyar, 1928, Culex (Melanoconion) rachoui Duret, 1968, Culex (Melanoconion) theobaldi (Lutz), 1904, Culex (Melanoconion) vaxusDyar, 1920, Culex (Melanoconion) angularis Sá & Sallum n. sp., Culex (Melanoconion) spiniformis Sá & Hutchings n. sp., Culex (Melanoconion) longistriatus Sá & Hutchings n. sp., Culex (Melanoconion) anelesDyar & Ludlow, 1922, Culex (Melanoconion) apeteticus Howard, Dyar & Ludlow, 1913, and Culex (Melanoconion) bibulusDyar, 1920. The last three species were resurrected from synonymy of either Cx. educator or Cx. vaxus. Descriptions, differential diagnoses, bionomics, and geographical data are provided for each species when available.

Reaching the malaria elimination goal in Brazil: a spatial analysis and time-series study.

BACKGROUND: Since 2015, the Global Technical Strategy (GTS) for Malaria 2016-2030 has been adopted by the World Health Organization (WHO) as a comprehensive framework to accelerate progress for malaria elimination in endemic countries. This strategy sets the target of reducing global malaria incidence and mortality rates by 90% in 2030. Here it is sought to evaluate Brazil's achievements towards reaching the WHO GTS milestone in 2030. Considering the total number of new malaria cases in 2015, the main research question is: will Brazil reach the malaria elimination goal in 2030? METHODS: Analytical strategies were undertaken using the SIVEP-malaria official databases of the Brazilian Malaria Control Programme for the Brazilian Amazon region from 2009 to 2020. Spatial and time-series analyses were applied for identifying municipalities that support the highest numbers of malaria cases over the years. Forecast analysis was used for predicting the estimated number of new cases in Brazil in 2025-2050. RESULTS: Brazil has significantly reduced the number of new malaria cases in 2020 in comparison with 2015 in the states of Acre (- 56%), Amapá (- 75%), and Amazonas (- 21%); however, they increased in the states of Pará (156%), Rondônia (74%), and Roraima (362%). Forecast of the predicted number of new malaria cases in 2030 is 74,764 (95% CI: 41,116-141,160) in the Brazilian Amazon. CONCLUSIONS: It is likely that Brazil will reduce the number of new malaria cases in the Brazilian Amazon in 2030 in relation to that in 2015. Herein forecast shows a reduction by 46% (74,754 in 2030 forecast/137,982 in 2015), but this reduction is yet far from the proposed reduction under the WHO GTS 2030 milestone (90%). Stable and unbeatable transmission in the Juruá River Valley, Manaus, and Lábrea still support endemic malaria in the Brazilian Amazon. Today's cross-border malaria is impacting the state of Roraima unprecedently. If this situation is maintained, the malaria elimination goal (zero cases) may not be reached before 2050. An enhanced political commitment is vital to ensure optimal public health intervention designs in the post-2030 milestones for malaria elimination.

Assessing the effect of Aedes (Stegomyia) aegypti (Linnaeus, 1762) control based on machine learning for predicting the spatiotemporal distribution of eggs in ovitraps.

Background: Aedes aegypti is the dominant vector of several arboviruses that threaten urban populations in tropical and subtropical countries. Because of the climate changes and the spread of the disease worldwide, the population at risk of acquiring the disease is increasing. Methods: This study investigated the impact of the larval habitats control (CC), nebulization (NEB), and both methods (CC + NEB) using the distribution of Ae. aegypti eggs collected in urban area of Santa Bárbara d'Oeste, São Paulo State, Brazil. A total of 142,469 eggs were collected from 2014 to 2017. To verify the effects of control interventions, a spatial trend, and a predictive machine learning modeling analytical approaches were adopted. Results: The spatial analysis revealed sites with the highest probability of Ae. aegypti occurrence and the machine learning generated an asymmetric histogram for predicting the presence of the mosquito. Results of analyses showed that CC, NEB, and CC + NEB control methods had a negative impact on the number of eggs collected in ovitraps, with effects on the distribution of eggs in the three weeks following the treatments, according to the predictive machine learning modeling. Conclusions: The vector control interventions are essential to decrease both occurrence of the mosquito vectors and urban arboviruses. The inference processes proposed in this study revealed the relative causal impact of distinct mosquito control interventions. The spatio-temporal and the machine learning analysis are relevant and Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation robust analytical approach to be employed in surveillance and monitoring the results of public health programs focused on combating urban arboviruses.

Molecular Analysis Reveals a High Diversity of Anopheline Mosquitoes in Yanomami Lands and the Pantanal Region of Brazil.

Identifying the species of the subfamily Anophelinae that are Plasmodium vectors is important to vector and malaria control. Despite the increase in cases, vector mosquitoes remain poorly known in Brazilian indigenous communities. This study explores Anophelinae mosquito diversity in the following areas: (1) a Yanomami reserve in the northwestern Amazon Brazil biome and (2) the Pantanal biome in southwestern Brazil. This is carried out by analyzing cytochrome c oxidase (COI) gene data using Refined Single Linkage (RESL), Assemble Species by Automatic Partitioning (ASAP), and tree-based multi-rate Poisson tree processes (mPTP) as species delimitation approaches. A total of 216 specimens collected from the Yanomami and Pantanal regions were sequenced and combined with 547 reference sequences for species delimitation analyses. The mPTP analysis for all sequences resulted in the delimitation of 45 species groups, while the ASAP analysis provided the partition of 48 groups. RESL analysis resulted in 63 operational taxonomic units (OTUs). This study expands our scant knowledge of anopheline species in the Yanomami and Pantanal regions. At least 18 species of Anophelinae mosquitoes were found in these study areas. Additional studies are now required to determine the species that transmit Plasmodium spp. in these regions.

Susceptibility of Field-Collected Nyssorhynchus darlingi to Plasmodium spp. in Western Amazonian Brazil.

Mosquito susceptibility to Plasmodium spp. infection is of paramount importance for malaria occurrence and sustainable transmission. Therefore, understanding the genetic features underlying the mechanisms of susceptibility traits is pivotal to assessing malaria transmission dynamics in endemic areas. The aim of this study was to investigate the susceptibility of Nyssorhynchus darlingi-the dominant malaria vector in Brazil-to Plasmodium spp. using a reduced representation genome-sequencing protocol. The investigation was performed using a genome-wide association study (GWAS) to identify mosquito genes that are predicted to modulate the susceptibility of natural populations of the mosquito to Plasmodium infection. After applying the sequence alignment protocol, we generated the variant panel and filtered variants; leading to the detection of 202,837 SNPs in all specimens analyzed. The resulting panel was used to perform GWAS by comparing the pool of SNP variants present in Ny. darlingi infected with Plasmodium spp. with the pool obtained in field-collected mosquitoes with no evidence of infection by the parasite (all mosquitoes were tested separately using RT-PCR). The GWAS results for infection status showed two statistically significant variants adjacent to important genes that can be associated with susceptibility to Plasmodium infection: Cytochrome P450 (cyp450) and chitinase. This study provides relevant knowledge on malaria transmission dynamics by using a genomic approach to identify mosquito genes associated with susceptibility to Plasmodium infection in Ny. darlingi in western Amazonian Brazil.

Vector role and human biting activity of Anophelinae mosquitoes in different landscapes in the Brazilian Amazon.

BACKGROUND: Environmental disturbance, deforestation and socioeconomic factors all affect malaria incidence in tropical and subtropical endemic areas. Deforestation is the major driver of habitat loss and fragmentation, which frequently leads to shifts in the composition, abundance and spatial distribution of vector species. The goals of the present study were to: (i) identify anophelines found naturally infected with Plasmodium; (ii) measure the effects of landscape on the number of Nyssorhynchus darlingi, presence of Plasmodium-infected Anophelinae, human biting rate (HBR) and malaria cases; and (iii) determine the frequency and peak biting time of Plasmodium-infected mosquitoes and Ny. darlingi. METHODS: Anopheline mosquitoes were collected in peridomestic and forest edge habitats in seven municipalities in four Amazon Brazilian states. Females were identified to species and tested for Plasmodium by real-time PCR. Negative binomial regression was used to measure any association between deforestation and number of Ny. darlingi, number of Plasmodium-infected Anophelinae, HBR and malaria. Peak biting time of Ny. darlingi and Plasmodium-infected Anophelinae were determined in the 12-h collections. Binomial logistic regression measured the association between presence of Plasmodium-infected Anophelinae and landscape metrics and malaria cases. RESULTS: Ninety-one females of Ny. darlingi, Ny. rangeli, Ny. benarrochi B and Ny. konderi B were found to be infected with Plasmodium. Analysis showed that the number of malaria cases and the number of Plasmodium-infected Anophelinae were more prevalent in sites with higher edge density and intermediate forest cover (30-70%). The distance of the drainage network to a dwelling was inversely correlated to malaria risk. The peak biting time of Plasmodium-infected Anophelinae was 00:00-03:00 h. The presence of Plasmodium-infected mosquitoes was higher in landscapes with > 13 malaria cases. CONCLUSIONS: Nyssorhynchus darlingi, Ny. rangeli, Ny. benarrochi B and Ny. konderi B can be involved in malaria transmission in rural settlements. The highest fraction of Plasmodium-infected Anophelinae was caught from midnight to 03:00 h. In some Amazonian localities, the highest exposure to infectious bites occurs when residents are sleeping, but transmission can occur throughout the night. Forest fragmentation favors increases in both malaria and the occurrence of Plasmodium-infected mosquitoes in peridomestic habitat. The use of insecticide-impregnated mosquito nets can decrease human exposure to infectious Anophelinae and malaria transmission.

Anthropogenic landscape decreases mosquito biodiversity and drives malaria vector proliferation in the Amazon rainforest.

Inter-relationships among mosquito vectors, Plasmodium parasites, human ecology, and biotic and abiotic factors, drive malaria risk. Specifically, rural landscapes shaped by human activities have a great potential to increase the abundance of malaria vectors, putting many vulnerable people at risk. Understanding at which point the abundance of vectors increases in the landscape can help to design policies and interventions for effective and sustainable control. Using a dataset of adult female mosquitoes collected at 79 sites in malaria endemic areas in the Brazilian Amazon, this study aimed to (1) verify the association among forest cover percentage (PLAND), forest edge density (ED), and variation in mosquito diversity; and to (2) test the hypothesis of an association between landscape structure (i.e., PLAND and ED) and Nyssorhynchus darlingi (Root) dominance. Mosquito collections were performed employing human landing catch (HLC) (peridomestic habitat) and Shannon trap combined with HLC (forest fringe habitat). Nyssorhynchus darlingi abundance was used as the response variable in a generalized linear mixed model, and the Shannon diversity index (H') of the Culicidae community, PLAND, and the distance house-water drainage were used as predictors. Three ED categories were also used as random effects. A path analysis was used to understand comparative strengths of direct and indirect relationships among Amazon vegetation classes, Culicidae community, and Ny. darlingi abundance. Our results demonstrate that Ny. darlingi is negatively affected by H´ and PLAND of peridomestic habitat, and that increasing these variables (one-unit value at ß0 = 768) leads to a decrease of 226 (P < 0.001) and 533 (P = 0.003) individuals, respectively. At the forest fringe, a similar result was found for H' (ß1 = -218; P < 0.001) and PLAND (ß1 = -337; P = 0.04). Anthropogenic changes in the Amazon vegetation classes decreased mosquito biodiversity, leading to increased Ny. darlingi abundance. Changes in landscape structure, specifically decreases in PLAND and increases in ED, led to Ny. darlingi becoming the dominant species, increasing malaria risk. Ecological mechanisms involving changes in landscape and mosquito species composition can help to understand changes in the epidemiology of malaria.