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Background: In Brazilian Amazon, deforestation and other anthropogenic activities as a consequence of human occupation have created new and artificial larval habitats for anopheline mosquitoes, providing conditions for oviposition, development and expansion of malaria vector populations. Objectives: This study aimed to structurally characterize and describe the entomological and limnological parameters of Anopheles larval habitats from a malaria region in northern Brazilian Amazon. Methods: Fifty-two larval habitats were investigated in the District of Ilha de Santana, in the Brazilian state of Amapá, comprising fish farming tanks, ponds, and streams. For entomological parameters, the immature larvae were collected monthly from July 2019 to June 2020. For limnological parameters, the water samples were collected from 20 larval habitats during the sampling period. The data were analyzed using Generalized Linear Models, Multivariate analyses, and Kruskal-Wallis tests. Results: Fifty habitats were positive for Anopheles larvae and a total of nine species were collected. The fish farming tanks had the highest abundance of larvae compared with ponds and streams. Anopheles darlingi, Anopheles nuneztovari s.l. and Anopheles triannulatus were collected in 94% of the larval habitats and showed the highest positivity index. The degree of shade and the type of water of the breeding sites were important factors for the presence of the main malaria vector, A. darlingi. This species was the most affected by pH, total dissolved solids, electrical conductivity, and nitrate. Conclusions: Our findings indicate that fish farming tanks are major contributors to vector anopheline abundance and malaria transmission. Vector control strategies focused on these habitats are urgently needed. [ABSTRACT FROM AUTHOR]

Zika virus (ZIKV) is an RNA flavivirus (Flaviviridae family) endemic in tropical and subtropical regions that is transmitted to humans by Aedes (Stegomyia) species mosquitoes. The two main urban vectors of ZIKV are Aedes aegypti and Aedes albopictus, which can be found throughout Brazil. This study investigated ZIKV infection in mosquito species sampled from urban forest fragments in Manaus (Brazilian Amazon). A total of 905 non-engorged female Ae. aegypti (22 specimens) and Ae. albopictus (883 specimens) were collected using BG-Sentinel traps, entomological hand nets, and Prokopack aspirators during the rainy and dry seasons between 2018 and 2021. All pools were macerated and used to inoculate C6/36 culture cells. Overall, 3/20 (15%) Ae. aegypti and 5/241 (2%) Ae. albopictus pools screened using RT-qPCR were positive for ZIKV. No supernatants from Ae. aegypti were positive for ZIKV (0%), and 15 out of 241 (6.2%) Ae. albopictus pools were positive. In this study, we provide the first-ever evidence of Ae. albopictus naturally infected with ZIKV in the Amazon region. [ABSTRACT FROM AUTHOR]

Risk of spillover and spillback of mosquito-borne viruses in the neotropics, including yellow fever, dengue, Zika (Flaviviridae: Flavivirus), chikungunya, and Mayaro (Togaviridae: Alphavirus) viruses, is highest at ecotones where humans, monkeys, and mosquitoes coexist. With a view to identifying potential bridge vectors, we investigated changes in mosquito community composition and environmental variables at ground level at distances of 0, 500, 1000, and 2000 m from the edge of a rainforest reserve bordering the city of Manaus in the central Brazilian Amazon. During two rainy seasons in 2019 and 2020, we sampled 9,467 mosquitoes at 244 unique sites using BG-Sentinel traps, hand-nets, and Prokopack aspirators. Species richness and diversity were generally higher at 0 m and 500 m than at 1000 m and 2000 m, while mosquito community composition changed considerably between the forest edge and 500 m before stabilizing by 1000 m. Shifts in environmental variables mainly occurred between the edge and 500 m, and the occurrence of key taxa (Aedes albopictus, Ae. scapularis, Limatus durhamii, Psorophora amazonica, Haemagogus, and Sabethes) was associated with one or more of these variables. Sites where Ae. aegypti and Ae. albopictus were detected had significantly higher surrounding mean NDBI (Normalized Difference Built-up Index) values than sites where they were not detected, while the opposite was true for Sabethes mosquitoes. Our findings suggest that major changes in mosquito communities and environmental variables occur within 500 m of the forest edge, where there is high risk for contact with both urban and sylvatic vectors. By 1000 m, conditions stabilize, species diversity decreases, and forest mosquitoes predominate. Environmental variables associated with the occurrence of key taxa may be leveraged to characterize suitable habitat and refine risk models for pathogen spillover and spillback. Author summary: Mosquito-borne viruses, including yellow fever, dengue, Zika, chikungunya, and Mayaro viruses, derive from sylvatic transmission cycles involving forest mosquitoes and wild animals. Occasionally, these sylvatic viruses spill over into humans, which can lead to limited disease outbreaks or sustained human transmission by urban mosquitoes. When translocated by humans to new geographic regions, these viruses have potential to spill back into novel sylvatic cycles, creating a lasting threat to human health. Ecotones, such as forest edges, where humans, mosquitoes, and monkeys coexist, are at high risk of spillover and spillback. We investigated changes in mosquito community composition at incremental distances up to 2000 m into rainforest bordering the Amazonian city of Manaus, where the above viruses circulate in urban and sylvatic cycles. We also characterized mosquito habitat and analyzed associations between key vector species and environmental variables like temperature and vegetation. Our results show that mosquito communities and environmental variables change abruptly within 500 m of the forest edge, where there is high risk for contact of both monkeys and humans with both urban and forest mosquitoes. By 1000 m, conditions stabilize, and forest mosquitoes predominate. Environmental variables associated with the presence of particular mosquito taxa will help characterize suitable habitat for key vector species and refine spillover and spillback risk models for these viruses. [ABSTRACT FROM AUTHOR]

Haemagogus (Haemagogus) janthinomys (Dyar, 1921), the major neotropical vector of sylvatic yellow fever virus, is notoriously difficult to maintain in captivity. It has never been reared beyond an F1 generation, and almost no experimental transmission studies have been performed with this species since the 1940s. Herein we describe installment hatching, artificial blood feeding, and forced-mating techniques that enabled us to produce small numbers of F3 generation Hg. janthinomys eggs for the first time. A total of 62.8% (1562/2486) F1 generation eggs hatched during ≤10 four-day cycles of immersion in a bamboo leaf infusion followed by partial drying. Hatching decreased to 20.1% (190/944) in the F2 generation for eggs laid by mosquitoes copulated by forced mating. More than 85% (79/92) female F2 mosquitoes fed on an artificial blood feeding system. While we were unable to maintain a laboratory colony of Hg. janthinomys past the F3 generation, our methods provide a foundation for experimental transmission studies with this species in a laboratory setting, a critical capacity in a region with hyper-endemic transmission of dengue, Zika, and chikungunya viruses, all posing a risk of spillback into a sylvatic cycle. [ABSTRACT FROM AUTHOR]

The chorionic sculpturing of ten Brazilian sandfly species, Nyssomyia antunesi (Coutinho), N. whitmani (Antunes and Coutinho), Bichromomyia flaviscutellata (Mangabeira) , B. olmeca nociva (Young and Arias), Evandromyia walkeri (Newstead), E. williamsi (Antunes and Coutinho), Deanemyia maruaga (Alves, Freitas and Barrett), D. samueli (Deane), Viannamyia furcata (Mangabeira) and Lutzomyia dispar (Martins and Silva), was examined using scanning electron microscopy. Eggs of the last seven species, as well as the genera Deanemyia and Viannamyia , are described for the first time. In total, five patterns of chorionic sculpturing were found: polygonal, connected parallel ridges, unconnected parallel ridges, volcano-like and placoid. The last one is a new chorionic sculpture pattern, which was observed in D. samueli . These structures are illustrated and discussed. These results show that egg morphology can be used in phlebotomine taxonomy, both at generic and specific levels. [ABSTRACT FROM AUTHOR]

Recent studies have shown that Anopheles oswaldoi sensu lato comprises a cryptic species complex in South America. Anopheles konderi, which was previously raised to synonymy with An. oswaldoi, has also been suggested to form a species complex. An. oswaldoi has been incriminated as a malaria vector in some areas of the Brazilian Amazon, Colombia, Peru and Venezuela, but was not recognized as a vector in the remaining regions in its geographic distribution. The role of An. konderi as a malaria vector is unknown or has been misattributed to An. oswaldoi. The focus of this study was molecular identification to infer the evolutionary relationships and preliminarily delimit the geographic distribution of the members of these complexes in the Brazilian Amazon region. The specimens were sampled from 18 localities belonging to five states in the Brazilian Amazon and sequenced for two molecular markers: the DNA barcode region (COI gene of mitochondrial DNA) and Internal Transcribed Spacer 2 (ITS2 ribosomal DNA). COI (83 sequences) and ITS2 (27 sequences) datasets generated 43 and 10 haplotypes, respectively. Haplotype networks and phylogenetic analyses generated with the barcode region (COI gene) recovered five groups corresponding to An. oswaldoi s.s., An. oswaldoi B, An. oswaldoi A, An. konderi and An. sp. nr. konderi; all pairwise genetic distances were greater than 3%. The group represented by An. oswaldoi A exhibited three strongly supported lineages. The molecular dating indicated that the diversification process in these complexes started approximately 2.8 Mya, in the Pliocene. These findings confirm five very closely related species and present new records for these species in the Brazilian Amazon region. The paraphyly observed for the An. oswaldoi complex suggests that An. oswaldoi and An. konderi complexes may comprise a unique species complex named Oswaldoi-Konderi. Anopheles oswaldoi B may be a potential malaria vector in the extreme north of the Brazilian Amazon, whereas evidence of sympatry for the remaining species in other parts of the Brazilian Amazon (Acre, Amazonas, Pará and Rondônia) precluded identification of probable vectors in those areas. [ABSTRACT FROM AUTHOR]

Background: Anopheles nuneztovari sensu lato comprises cryptic species in northern South America, and the Brazilian populations encompass distinct genetic lineages within the Brazilian Amazon region. This study investigated, based on two molecular markers, whether these lineages might actually deserve species status. Methods: Specimens were collected in five localities of the Brazilian Amazon, including Manaus, Careiro Castanho and Autazes, in the State of Amazonas; Tucuruí, in the State of Pará; and Abacate da Pedreira, in the State of Amapá, and analysed for the COI gene (Barcode region) and 12 microsatellite loci. Phylogenetic analyses were performed using the maximum likelihood (ML) approach. Intra and inter samples genetic diversity were estimated using population genetics analyses, and the genetic groups were identified by means of the ML, Bayesian and factorial correspondence analyses and the Bayesian analysis of population structure. Results: The Barcode region dataset (N = 103) generated 27 haplotypes. The haplotype network suggested three lineages. The ML tree retrieved five monophyletic groups. Group I clustered all specimens from Manaus and Careiro Castanho, the majority of Autazes and a few from Abacate da Pedreira. Group II clustered most of the specimens from Abacate da Pedreira and a few from Autazes and Tucuruí. Group III clustered only specimens from Tucuruí (lineage III), strongly supported (97 %). Groups IV and V clustered specimens of A. nuneztovari s.s. and A. dunhami, strongly (98 %) and weakly (70 %) supported, respectively. In the second phylogenetic analysis, the sequences from GenBank, identified as A. goeldii, clustered to groups I and II, but not to group III. Genetic distances (Kimura-2 parameters) among the groups ranged from 1.60 % (between I and II) to 2.32 % (between I and III). Microsatellite data revealed very high intra-population genetic variability. Genetic distances showed the highest and significant values (P = 0.005) between Tucuruí and all the other samples, and between Abacate da Pedreira and all the other samples. Genetic distances, Bayesian (Structure and BAPS) analyses and FCA suggested three distinct biological groups, supporting the barcode region results. Conclusions: The two markers revealed three genetic lineages for A. nuneztovari s.l. in the Brazilian Amazon region. Lineages I and II may represent genetically distinct groups or species within A. goeldii. Lineage III may represent a new species, distinct from the A. goeldii group, and may be the most ancestral in the Brazilian Amazon. They may have differences in Plasmodium susceptibility and should therefore be investigated further. [ABSTRACT FROM AUTHOR]

Lutzomyia ( Nyssomyia ) anduzei has been recognized as a secondary vector of Leishmania guyanensis in the Brazilian Amazon region. Since L. anduzei is anthropophilic, co-exists in areas of high leishmaniasis transmission and has been found infected with L. guyanensis , the understanding of the vector population structure and of the process responsible for it is paramount to the vector management and control efforts. In this study we analyzed 74 and 67 sequences of the COI and Cytb loci, respectively, from mitochondrial DNA, aiming to estimate the intra-population genetic variability and population structure in six L. anduzei samples from the Brazilian Amazon region. For COI , we found 58 haplotypes, low to high ( F ST = 0.0310–0.4128) and significant ( P = 0.0033) genetic structure, and reduced gene flow among populations. The haplotype network yielded many reticulations that likely resulted from hypervariability in the locus. For Cytb , we observed 27 haplotypes, low to moderate ( F ST = 0.0077–0.1954) and nonsignificant ( P > 0.05) genetic structure for the majority of comparisons and extensive gene flow among populations, in line with the haplotypes network data. AMOVA analysis indicated that most of the variation occurred within populations (83.41%, 90.94%); nevertheless, there were significant differences ( Φ ST = 0.0906–0.1659; P = 0.00098; P = 0.00000) among them for both loci. The Mantel test showed that the genetic structure is not associated to an isolation-by-distance (IBD) model in either of both loci. These data suggest that L. anduzei is genetically very diverse. The genetic structure lacking IBD may be due to adaptation to local habitats and the low dispersal capacity of the sandflies, and both could lead to population fragmentation and geographic isolation. These findings have important implications for epidemiology, surveillance and vector control and may be a first step in understanding the evolutionary history of this species. [ABSTRACT FROM AUTHOR]

Background: Lutzomyia umbratilis (a probable species complex) is the main vector of Leishmania guyanensis in the northern region of Brazil. Lutzomyia anduzei has been implicated as a secondary vector of this parasite. These species are closely related and exhibit high morphological similarity in the adult stage; therefore, they have been wrongly identified, both in the past and in the present. This shows the need for employing integrated taxonomy. Methods: With the aim of gathering information on the molecular taxonomy and evolutionary relationships of these two vectors, 118 sequences of 663 base pairs (barcode region of the mitochondrial DNA cytochrome oxidase I - COI) were generated from 72 L. umbratilis and 46 L. anduzei individuals captured, respectively, in six and five localities of the Brazilian Amazon. The efficiency of the barcode region to differentiate the L. umbratilis lineages I and II was also evaluated. The data were analyzed using the pairwise genetic distances matrix and the Neighbor-Joining (NJ) tree, both based on the Kimura Two Parameter (K2P) evolutionary model. Results: The analyses resulted in 67 haplotypes: 32 for L. umbratilis and 35 for L. anduzei. The mean intra-specific genetic distance was 0.008 (0.002 to 0.010 for L. umbratilis; 0.008 to 0.014 for L. anduzei), whereas the mean interspecific genetic distance was 0.044 (0.041 to 0.046), supporting the barcoding gap. Between the L. umbratilis lineages I and II, it was 0.009 to 0.010. The NJ tree analysis strongly supported monophyletic clades for both L. umbratilis and L. anduzei, whereas the L. umbratilis lineages I and II formed two poorly supported monophyletic subclades. Conclusions: The barcode region clearly separated the two species and may therefore constitute a valuable tool in the identification of the sand fly vectors of Leishmania in endemic leishmaniasis areas. However, the barcode region had not enough power to separate the two lineages of L. umbratilis, likely reflecting incipient species that have not yet reached the status of distinct species [ABSTRACT FROM AUTHOR]

Background: Lutzomyia umbratilis is an important Leishmania guyanensis vector in South America. Previous studies have suggested differences in the vector competence between L. umbratilis populations situated on opposite banks of the Amazonas and Negro Rivers in the central Amazonian Brazil region, likely indicating a species complex. However, few studies have been performed on these populations and the taxonomic status of L. umbratilis remains unclear. Methodology/Principal Findings: Phylogeographic structure was estimated for six L. umbratilis samples from the central Amazonian region in Brazil by analyzing mtDNA using 1181 bp of the COI gene to assess whether the populations on opposite banks of these rivers consist of incipient or distinct species. The genetic diversity was fairly high and the results revealed two distinct clades ( = lineages) with 1% sequence divergence. Clade I consisted of four samples from the left bank of the Amazonas and Negro Rivers, whereas clade II comprised two samples from the right bank of Negro River. No haplotypes were shared between samples of two clades. Samples within clades exhibited low to moderate genetic differentiation (FST =20.0390-0.1841), whereas samples between clades exhibited very high differentiation (FST = 0.7100- 0.8497) and fixed differences. These lineages have diverged approximately 0.22 Mya in the middle Pleistocene. Demographic expansion was detected for the lineages I and II approximately 30,448 and 15,859 years ago, respectively, in the late Pleistocene. Conclusions/Significance: The two genetic lineages may represent an advanced speciation stage suggestive of incipient or distinct species within L. umbratilis. These findings suggest that the Amazonas and Negro Rivers may be acting as effective barriers, thus preventing gene flow between populations on opposite sides. Such findings have important implications for epidemiological studies, especially those related to vector competence and anthropophily, and for vector control strategies. In addition, L. umbratilis represents an interesting example in speciation studies. [ABSTRACT FROM AUTHOR]

• Anopheles konderi include at least two putative species in Oswaldoi-konderi Complex. • Morphological and molecular data obtained in this study were able to separate the two species. • Anopheles tadei n. sp. described here, is geographically sympatric to An. konderi s. s. [Display omitted] The Oswaldoi-konderi Complex (Anopheles, Nyssorhynchus) is composed of five species that have been distinguished and delimited using DNA sequences of mitochondrial and nuclear genes. At least two species of the complex have been formally described, namely Anopheles oswaldoi s.s. and An. konderi ; however, the identity of An. konderi s.s. is unclear because two morphologically similar species co-exist in the type-locality in the municipality of Coari, Amazonas state, Brazil. Moreover, the study of resurrection and designation of the neotype of An. konderi s.s. included a mixture of both forms. In the present study, mosquitoes were collected in Coari to establish the molecular identity of An. konderi s.s. and describe a new species based on morphological and molecular data. Six females were collected and separated individually for oviposition. The parental progenies were obtained from field collected females, fourth-instar larva, pupa, and female and male were employed for morphological characterization. Genomic DNA from one fourth-instar larva of each progeny was extracted and sequenced for the mtDNA COI barcode region, CAD gene, and the ITS2 rDNA nuclear region to establish the molecular identity of the two morphological forms of An. konderi s.l. The An. konderi neotype was re-examined. The morphological and molecular analyses revealed two distinct groups: the first group was identical to the neotype of An. konderi s.s., whereas the second was found to belong to the group informally referred to as An. sp. near konderi or An. konderi B, herein described as Anopheles tadei n. sp. [ABSTRACT FROM AUTHOR]

Leishmaniasis is considered one of the six most important infectious diseases in the world. In spite of its importance, the leishmaniasis is one of the world's most neglected tropical diseases. Bichromomyia flaviscutellata sensu lato is a complex composed of at least three species: B. flaviscutellata sensu stricto, B. reducta and B. olmeca. The latter is composed of three subspecies: B. olmeca olmeca , B. olmeca bicolor and B. olmeca nociva , which are distributed from Central America to South America. Of these, B. flaviscutellata s.s. is recognized as the main vector of Leishmania amazonensis in Brazil. The present study aimed to identify molecularly the species and subspecies of the B. flaviscutellata complex using the 5′ region of the COI gene (Barcode region). A total of 44 specimens, comprising 22 B. flaviscutellata s.s. and 22 B. olmeca nociva , were analyzed from six localities in the Brazilian Amazon: five in the State of Amazonas (Autazes, Manaus, Pitinga, Novo Airão, and Rio Preto da Eva), and one in the State of Pará (Serra do Cachorro). Three sequences from B. olmeca olmeca and one of B. olmeca bicolor from GenBank were also added to the dataset, totaling 48 sequences with a length of 549 base pairs (bp). The total dataset generated 28 haplotypes and four disconnected networks. Phylogenetic analyses using three algorithms (Neighbor-Joining [NJ], Maximum Likelihood [ML] and Bayesian Inference [BI]) generated similar topologies and most clades were from moderately to highly supported. The phylogenetic relationship, together with genetic distance values (1%) and haplotypes networks, confirm the position of B. olmeca bicolor as a subspecies of B. olmeca olmeca. However, B. olmeca nociva was closer phylogenetically to B. flaviscutellata s.s. than to B. olmeca olmeca and B. olmeca bicolor. Additionally, the haplotype network separated B. olmeca nociva from B. olmeca olmeca and B. olmeca bicolor. These findings, combined with previous morphological data, suggest that the B. olmeca nociva should be elevated to full-species status. The findings of this study also found that B. flaviscutellata s.s. populations may be in process of forming lineages. • Molecular taxonomy and phylogenetic studies were conducted in the Bichromomyia flaviscutellata complex from the Brazilian Amazon region • The intra- and interspecific genetic distances between species and subspecies of B. flaviscutellata complex showed an extensive barcoding gap. • B. olmeca nociva subspecies is a distinct species from the B. olmeca olmeca and B. olmeca bicolor subspecies • B. flaviscutellata s.s. populations may be under the process of split lineages. [ABSTRACT FROM AUTHOR]

Population genetics of Aedes aegypti from fifteen locations of Brazil was studied. The findings revealed two major genetic clusters and each one showed genetic sub-divisions within them. • Population genetics of Aedes aegypti from Brazil using microsatellites loci. • Moderate levels of intra-population genetic diversity were observed. • Two major genetic clusters were observed for Aedes aegypti in Brazil. • These differences may influence the vector competence and control measures. Aedes aegypti , being the principal vector of dengue (DENV1 to 4), chikungunya and Zika viruses, is considered as one of the most important mosquito vectors. In Brazil, despite regular vector control programs, Ae. aegypti still persists with high urban density in all the states. This study aimed to estimate the intra and inter population genetic diversity and genetic structure among 15 Brazilian populations of Ae. aegypti based on 12 microsatellite loci. A total of 510 specimens were analyzed comprising eight locations from northern (Itacoatiara, Manaus, Novo Airão, Boa Vista, Rio Branco, Porto Velho, Guajará-Mirim and Macapá), three from southeastern (Araçatuba, São José de Rio Preto and Taubaté), one from southern (Foz do Iguaçu), one from central west (Cuiabá) and two from northeastern (Campina Grande and Teresina) regions of Brazil. Genetic distances (pairwise values of F ST and N m) and the analysis of molecular variance (AMOVA) were statistically significant, independent of geographic distances among the sites analyzed, indicating that them are under a complex dynamic process that influence the levels of gene flow within and among regions of the country. Bayesian analysis in STRUCTURE revealed the existence of two major genetic clusters, as well as there was genetic substructure within them; these results were confirmed by AMOVA, BAPS and DAPC analyses. This differentiation is the cumulative result of several factors combined as events of multiple introduction, passive dispersal, environmental and climatic conditions, use of insecticides, cycles of extinction and re-colonization followed by microevolutionary processes throughout the country. Isolation by distance also contributed to this differentiation, especially among geographically closer localities. These genetic differences may affect its vector competence to transmit dengue, chikungunya, Zika and the response to vector control programs. [ABSTRACT FROM AUTHOR]

The characterization of behavioral patterns allows a better understanding of the transmission dynamics and the design of more effective malaria vector control strategies. This study analyzed the behavioral patterns of the Anopheles species of the Coração district situated in the northeast of the Brazilian Amazon region. The behavioral patterns of the anopheline species were measured based on the 36 collection sites of this district from December 2010 to November 2011. Collections of four hours for three consecutive nights each month and four 12-h collections, comprising two in the rainy season and two in the dry season, were performed. Furthermore, to infer the anthropophily and zoophily indexes, four additional four-hour collections were performed. The samples were also evaluated for parity rate and natural infectivity for Plasmodium spp. A total of 1689 anophelines were captured, comprising of nine species and two subgenera ( Nyssorhynchus – six species, and Anopheles – three species). Anopheles darlingi was the most abundant and widely distributed species in the area, followed by A. braziliensis and A.marajoara . Anopheles darlingi and A. marajoara were the only species present in the four collections of 12-h, but only A. darlingi showed activity throughout night. Anopheles darlingi was the most anthropophilic species (AI = 0.40), but the zoophily index was higher (ZI = 0.60), revealing an eclectic and opportunistic behavior. Of the six most frequent species, A. nuneztovari s.l. was the most zoophilic species (ZI = 1.00). All captured species showed predominance towards biting in outdoor environments. Anopheles darlingi and A. braziliensis showed multimodal biting peaks, whereas A. marajoara revealed a stable pattern, with the biting peak after sunset. Using the PCR technique, no anopheline was found infected with the malaria parasite. Since A. darlingi and A. marajoara are recognized as important vectors in this region, the district of Coração may be considered as a highly potent area for transmission of malaria, therefore, the prevention and surveillance measures should be taken constantly to prevent the same. The role of A. braziliensis as malaria vector needs to be urgently investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] We tested for temporal genetic differences between Aedes aegypti populations from Manaus, Brazil, sampled in the rainy and dry seasons. [•] Genetic variability was similar in both seasons. [•] The samples from the rainy season were genetically homogeneous. [•] The samples from the dry season showed significant differentiation, due to reduced Ne values in two of the four samples analyzed. [•] These findings are important to help design new dengue control strategies. [Copyright &y& Elsevier]