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1.
J Med Entomol ; 59(2): 631-637, 2022 03 16.
Article de Anglais | MEDLINE | ID: mdl-35043213

RÉSUMÉ

High abundance of hematophagous mosquitoes of the genus Mansonia Blanchard, 1901 (Diptera: Culicidae) threatens human and domestic animal health and well-being. Knowledge of the biology of nuisance mosquito species is necessary to understand specific ecological and biological factors to enable rapid and effective monitoring measures for sustainable control programs. The establishment and dispersion of Mansonia species are associated with the occurrence of aquatic macrophytes species, which are indispensable for the development of larvae and pupae. To increase knowledge of the host plants for Mansonia immature stages in Porto Velho, Rondonia State, Brazil, specimens of four plant species, which occur across the tributaries of the Madeira River were sampled and inspected for the presence of egg batches, larvae, and pupae. A total of 1,386 larvae and pupae of Mansonia spp. were collected attached to the roots of Eichhornia crassipes (Mart.) Solms (Commelinales: Pontederiaceae), Pistia stratiotes L. (Alismatales: Araceae), and Limnobium laevigatum (Humb. and Bonpl. Ex Willd.) Heine (Alismatales: Hydrocharitaceae). The novel association of Mansonia species with L. laevigatum is presented. Egg batches of Mansonia spp. were found only on Salvinia molesta D.S. Mitch. (Salviniales: Salviniaceae). Possible differences in the roles played by E. crassipes and S. molesta in the reproductive cycle of Mansonia spp. in the surveyed area are discussed. All species of host plants including E. crassipes, P. stratiotes, S. molesta, and L. laevigatum should be considered when planning macrophyte management for the control of Mansonia species.


Sujet(s)
Araceae , Culicidae , Eichhornia , Malvaceae , Animaux , Brésil , Larve , Plantes , Pupe
2.
Sci Rep ; 9(1): 5356, 2019 03 29.
Article de Anglais | MEDLINE | ID: mdl-30926833

RÉSUMÉ

The primary Brazilian malaria vector, Nyssorhynchus darlingi (formerly Anopheles darlingi), ranges from 0°S-23°S across three biomes (Amazonia, Cerrado, Mata Atlântica). Rising temperatures will increase mosquito developmental rates, and models predict future malaria transmission by Ny. darlingi in Brazil will shift southward. We reared F1 Ny. darlingi (progeny of field-collected females from 4 state populations across Brazil) at three temperatures (20, 24, 28 °C) and measured key life-history traits. Our results reveal geographic variation due to both genetic differences among localities and plastic responses to temperature differences. Temperature significantly altered all traits: faster larval development, shorter adult life and overall lifespan, and smaller body sizes were seen at 28 °C versus 20 °C. Low-latitude Amazonia mosquitoes had the fastest larval development at all temperatures, but at 28 °C, average development rate of high-latitude Mata Atlântica mosquitoes was accelerated and equivalent to low-latitude Amazonia. Body size of adult mosquitoes from the Mata Atlântica remained larger at all temperatures. We detected genetic variation in the plastic responses among mosquitoes from different localities, with implications for malaria transmission under climate change. Faster development combined with larger body size, without a tradeoff in adult longevity, suggests vectorial capacities of some Mata Atlântica populations may significantly increase under warming climates.


Sujet(s)
Caractéristiques du cycle biologique , Paludisme/épidémiologie , Vecteurs moustiques/physiologie , Température , Adaptation physiologique , Brésil , Géographie , Longévité , Paludisme/prévention et contrôle , Paludisme/transmission , Vecteurs moustiques/parasitologie
3.
J Med Entomol ; 53(6): 1330-1347, 2016 11.
Article de Anglais | MEDLINE | ID: mdl-27480098

RÉSUMÉ

The mosquito fauna (Culicidae) from remote northern areas of the State of Amazonas were sampled using Centers for Disease Control and Prevention, Shannon, Malaise, and Suspended traps, together with net sweeping and immature collections. One hundred and seven collections were performed in five localities along the Padauari River, State of Amazonas, Brazil, during June 2010. The 20,557 mosquitoes collected are distributed in 17 genera, representing 117 different species, of which four are new distributional records for the State of Amazonas. Furthermore, there are 10 morphospecies that may represent undescribed new taxa, eight of which are also new records for the State of Amazonas. The genus Culex had the highest number of species and the largest number of individuals. Aedes and Psorophora both represented 10% of the total sample and had the second highest number of species and individuals. The most abundant species was Culex (Melanoconion) gnomatos Sallum, Hutchings & Ferreira, followed by Aedes (Ochlerotatus) fulvus (Wiedemann), Culex (Melanoconion) vaxus Dyar, Culex (Melanoconion) portesi Senevet & Abonnenc, Psorophora (Janthinosoma) amazonica Cerqueira, Culex (Culex) mollis Dyar & Knab, Psorophora (Janthinosoma) albigenu (Peryassú), and Culex (Melanoconion) theobaldi Lutz. The epidemiological and ecological implications of mosquito species found are discussed and are compared with other mosquito inventories from the Amazon region. The results represent the most diverse standardized inventory of mosquitoes along the Padauari River, with the identification of 127 species-level taxa distributed in five localities, within two municipalities (Barcelos and Santa Isabel do Rio Negro).


Sujet(s)
Répartition des animaux , Biodiversité , Culicidae/physiologie , Animaux , Brésil , Culicidae/classification , Culicidae/croissance et développement , Femelle , Larve/croissance et développement , Mâle , Densité de population , Pupe/croissance et développement
4.
J Med Entomol ; 53(4): 790-797, 2016 07.
Article de Anglais | MEDLINE | ID: mdl-27146682

RÉSUMÉ

Mitochondrial genome sequences are widely used as molecular markers for phylogenetic studies of mosquito species complexes, such as the Anopheles albitarsis complex. Except for a few studies that employed a limited number of nuclear or mitochondrial loci to address the genetic structure and species status of Anopheles cruzii, Anopheles bellator, and Anopheles homunculus, little is known about genetic markers that can be employed in studies focusing on Kerteszia species. The complete mitochondrial genomes of seven specimens of An. bellator, An. cruzii, An. homunculus, and Anopheles laneanus were sequenced using long-range polymerase chain reaction and Illumina sequencing. The mitochondrial genomes varied from 15,446 to 15,738 bp in length and contained 37 genes (13 protein-encoding genes, 2 rRNA genes [12S rRNA and 16S rRNA] and 22 tRNA genes), and the AT-rich control region, as all do other Anopheles mitochondrial genomes sequenced to date. Specimens from four populations of An. cruzii showed differences in codon composition.


Sujet(s)
Anopheles/génétique , Génome d'insecte , Génome mitochondrial , Animaux , Brésil , Femelle , Mâle , Analyse de séquence d'ADN
5.
J Med Entomol ; 52(5): 858-65, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-26336257

RÉSUMÉ

Caatinga is one of the least known biomes of Brazil in relation to biodiversity. The dry condition of semiarid areas has been associated in the past with low richness of fauna and flora, not encouraging studies in this region. There is a lack of mosquito records including anophelines. Thus, to investigate the biodiversity of Anopheles mosquitoes in the Caatinga biome, we collected immature mosquitoes in aquatic habitats in a conservation reserve located in the northwestern portion of Sergipe state. The captured specimens were initially identified as Anopheles albitarsis l.s. and Anopheles argyritarsis l.s. To confirm the morphological identification, sequences were generated by cytochrome oxidase subunit I mitocondrial gene. The results showed that the specimens belong to the species Anopheles oryzalimnetes, An. argyritarsis, and Anopheles sawyeri. These are the first records of these species in this region. The presence of Anopheles in the Caatinga biome, which is characterized by arid and semiarid climatic conditions, encourages the interest in the study of biological, physiological, and behavioral adaptations, selected over time, which allow these mosquito populations to survive through the long periods of drought that is characteristic of this region.


Sujet(s)
Répartition des animaux , Anopheles/physiologie , Animaux , Anopheles/génétique , Anopheles/croissance et développement , Biodiversité , Brésil , Codage à barres de l'ADN pour la taxonomie , Complexe IV de la chaîne respiratoire/génétique , Complexe IV de la chaîne respiratoire/métabolisme , Femelle , Protéines d'insecte/génétique , Protéines d'insecte/métabolisme , Larve/génétique , Larve/croissance et développement , Larve/physiologie , Mâle , Protéines mitochondriales/génétique , Protéines mitochondriales/métabolisme , Données de séquences moléculaires , Phylogenèse , Pupe/génétique , Pupe/croissance et développement , Pupe/physiologie , Analyse de séquence d'ADN , Spécificité d'espèce
6.
J Med Entomol ; 51(5): 915-24, 2014 Sep.
Article de Anglais | MEDLINE | ID: mdl-25276918

RÉSUMÉ

A variety of traps are used for sampling, surveillance, and monitoring of mosquito vector species associated with parasite and pathogen transmission. Here, we assessed the performance of the Mosquito Magnet Independence trap with Lurex3 (MMI), by comparing its effectiveness with those of a Centers forDisease Control and Prevention light trap (CDC-LT) and CDC with CO2 and Lurex3 (CDC-A) in a dense tropical rainforest. Multivariate generalized linear models revealed significant differences among the traps regarding mosquito composition and abundance (deviance = 768; P = 0.016). Variance analyses indicated that the MMI captured significantly more mosquitoes compared with CDC-LT (P < 0.01) and CDC-A (P < 0.03). The abundance values did not significantly differ between the CDC-LT and CDC-A traps (P = 0.7). Mosquito species richness was higher from the MMI than from the CDC-LT and CDC-A traps. Furthermore, medically important mosquito species captured by the three traps showed high association with MMI. These results suggest the potential to use the MMI in studies aiming to obtain entomological surveillance information about medically important mosquitoes that occur in tropical rainforest areas. The MMI could also be used in faunal studies focusing on increasing knowledge about mosquito diversity. Considering the present positive results, the effectiveness of the MMI should additionally be evaluated in other Brazilian natural ecosystems. Further studies are also needed to address demographic data from the mosquito population sampled by the MMI.


Sujet(s)
Culicidae/physiologie , Écosystème , Lutte contre les moustiques/instrumentation , Arbres , Animaux , Comportement animal , Brésil , Lutte contre les moustiques/méthodes , Dynamique des populations
7.
Neotrop Entomol ; 40(1): 145-7, 2011.
Article de Anglais | MEDLINE | ID: mdl-21437497

RÉSUMÉ

This is the first record of Culex (Culex) brethesi (Dyar) in Rio Grande do Sul state, Brazil. The species was identified from specimens collected in a sand bar vegetation with the aid of a Nasci's trap, during an expedition for surveillance of the West Nile Virus in July of 2006, in the city of Mostardas, Rio Grande do Sul, Brazil.


Sujet(s)
Culex , Animaux , Brésil , Culex/anatomie et histologie , Densité de population
8.
J Med Entomol ; 45(6): 970-81, 2008 Nov.
Article de Anglais | MEDLINE | ID: mdl-19058619

RÉSUMÉ

Anopheles (Nyssorhynchus) benarrochi s.l., Anopheles (Nyssorhynchus) oswaldoi s.l., and Anopheles (Nyssorhynchus) konderi s.l. collected in Acrelandia, state of Acre, Brazil, were identified based on morphological characters of the male genitalia, fourth-instar larvae, and pupae. Morphological variation was observed in the male genitalia of these species in comparison with specimens from other localities in Brazil. DNA sequence from the nuclear ribosomal second internal transcribed spacer of individuals identified as An. benarrochi s.l. by using male genitalia characteristics showed that the various morphological forms are conspecific but are distinct from An. benarrochi B from Colombia. Anopheles konderi s.l. and An. oswaldoi s.l. both misidentified as An. oswaldoi s.s. (Peryassti) throughout Brazil, may actually comprise at least two undescribed species. Diagnostic morphological characteristics of the male genitalia are provided to distinguish Anopheles benarrochi s.l., Anopheles oswaldoi s.l., and Anopheles konderi s.l. from morphologically similar species. Incrimination of An. oswaldoi s.s. in malaria transmission in Brazil needs further investigation because other undescribed species from Acre may have been confounded with this taxon.


Sujet(s)
Anopheles/classification , Espaceur de l'ADN ribosomique/génétique , Animaux , Anopheles/anatomie et histologie , Anopheles/génétique , Séquence nucléotidique , Brésil , Système génital/anatomie et histologie , Mâle , Données de séquences moléculaires , Alignement de séquences , Analyse de séquence d'ADN
9.
J Med Virol ; 80(2): 323-9, 2008 Feb.
Article de Anglais | MEDLINE | ID: mdl-18098149

RÉSUMÉ

Nucleotide sequence analyses of the SH gene of 18 mumps virus isolates collected in the 2006-2007 parotitis epidemic in the state of São Paulo identified a new genotype, designated genotype M. This new designation fulfills all the parameters required to define a new mumps virus genotype. The parameters were established by an expert panel in collaboration with the World Health Organization (WHO) in 2005. This information will enhance the mumps virus surveillance program both at the national and global levels.


Sujet(s)
Virus des oreillons/classification , Virus des oreillons/génétique , Oreillons/virologie , Adolescent , Adulte , Séquence d'acides aminés , Brésil/épidémiologie , Enfant , Enfant d'âge préscolaire , Femelle , Génotype , Humains , Mâle , Adulte d'âge moyen , Données de séquences moléculaires , Oreillons/épidémiologie , Virus des oreillons/isolement et purification , ARN viral/génétique , Analyse de séquence d'ADN , Protéines virales
10.
Hereditas ; 143(2006): 62-7, 2006 Dec.
Article de Anglais | MEDLINE | ID: mdl-17362336

RÉSUMÉ

The C-banding pattern and the size and location of the nucleolar organizer regions (NORs) are described for the first time in Brazilian populations of Anopheles (Nyssorhynchus) albitarsis sensu lato. C-banding revealed variation in the size of the centromeric heterochromatic blocks in autosomal chromosomes and in the acrocentric (X) and puntiform (Y) sex chromosomes. Fluorescence in situ hybridization showed that the NORs were located in the pericentromeric region of the sex (XX/XY) chromosomes and that this coincided with the number and location of centromeric constitutive heterochromatin blocks previously revealed by C-banding. The NORs varied in size among the homologues of the three populations. These findings of the populations studied support the hypothesis that the stability of NORs in the A. albitarsis complex is characterized by the presence of clustered and conserved sites in a unique pair of chromosomes.


Sujet(s)
Anopheles/génétique , Chromosomes , Animaux , Anopheles/classification , Brésil , Zébrage chromosomique , Hybridation fluorescente in situ , Caryotypage , Métaphase , Chromosome X , Chromosome Y
11.
Med Vet Entomol ; 19(4): 428-41, 2005 Dec.
Article de Anglais | MEDLINE | ID: mdl-16336308

RÉSUMÉ

Abstract. An entomological inventory was conducted between 1993 and 1996 to obtain information on the diversity of mosquitoes (Diptera: Culicidae) in the Jaú National Park, State of Amazonas, Brazil. A total of 10,159 adult (91%) and immature mosquito specimens, representing 130 taxa (species + morphospecies) in 16 genera, was collected. A species list for the family Culicidae is presented, including 30 new records for the State of Amazonas. The collecting localities were restricted to the alluvial subregion of the Open Tropical Forest found in the park. Most of the specimens (71%) were collected in forest habitats and the rest in areas of second growth and peridomicile. The majority of immature specimens (46%) were collected in bodies of water along the edges of rivers, flooded forests, lakes and streams. Among the various collection methods used, the Centre for Disease Control (CDC) and Shannon traps together were responsible for capturing 60% of the adults. More than 90% of the material collected belongs to the genera Culex (65%), Psorophora (19%), Wyeomyia (4%), and Anopheles (3%), which together represent 70% of the identified taxa. The genus Culex presented the largest number of species (45). The species Culex (Melanoconion) vaxus, Cx. (Mel.) pedroi, Psorophora amazonica, Cx. (Mel.) portesi and Cx. (Mel.) theobaldi together (< 4% of the recorded species) represent more than 63% of the material collected and identified to the species level. The most abundant species was Cx. (Mel.) vaxus, representing 17% of the material identified to species. The possible epidemiological and ecological implications of the species hereby recorded in the Jaú National Park are presented and discussed.


Sujet(s)
Biodiversité , Culicidae/physiologie , Environnement , Manipulation d'échantillons/méthodes , Animaux , Brésil , Spécificité d'espèce
12.
Med Vet Entomol ; 19(2): 158-99, 2005 Jun.
Article de Anglais | MEDLINE | ID: mdl-15958025

RÉSUMÉ

Among Oriental anopheline mosquitoes (Diptera: Culicidae), several major vectors of forest malaria belong to the group of Anopheles (Cellia) leucosphyrus Dönitz. We have morphologically examined representative material (> 8000 specimens from seven countries) for taxonomic revision of the Leucosphyrus Group. Six new species are here described from adult, pupal and larval stages (with illustrations of immature stages) and formally named as follows: An. latens n. sp. (= An. leucosphyrus species A of Baimai et al., 1988b), An. cracens n. sp., An. scanloni n. sp., An. baimaii n. sp. (formerly An. dirus species B, C, D, respectively), An. mirans n. sp. and An. recens n. sp. Additionally, An. elegans (James) is redescribed and placed in the complex of An. dirus Peyton & Harrison (comprising An. baimaii, An. cracens, An. dirus, An. elegans, An. nemophilous Peyton and Ramalingam, An. scanloni and An. takasagoensis Morishita) of the Leucosphyrus Subgroup, together with An. baisasi Colless and the An. leucosphyrus complex (comprising An. balabacensis Baisas, An. introlatus Baisas, An. latens and An. leucosphyrus). Hence, the former Elegans Subgroup is renamed the Hackeri Subgroup (comprising An. hackeri Edwards, An. pujutensis Colless, An. recens and An. sulawesi Waktoedi). Distribution data and bionomics of the newly defined species are given, based on new material and published records, with discussion of morphological characters for species distinction and implications for ecology and vector roles of such species. Now these and other members of the Leucosphyrus Group are identifiable, it should be possible to clarify the medical importance and distribution of each species. Those already regarded as vectors of human malaria are: An. baimaii[Bangladesh, China (Yunnan), India (Andamans, Assam, Meghalaya, West Bengal), Myanmar, Thailand]; An. latens[Borneo (where it also transmits Bancroftian filariasis), peninsular Malaysia, Thailand]; probably An. cracens (Sumatra, peninsular Malaysia, Thailand); presumably An. scanloni (Thailand); perhaps An. elegans (the Western Ghat form of An. dirus, restricted to peninsular India); but apparently not An. recens (Sumatra) nor An. mirans[Sri Lanka and south-west India (Karnataka, Kerala, Tamil Nadu)], which is a natural vector of simian malarias. Together with typical An. balabacensis, An. dirus and An. leucosphyrus, therefore, the Leucosphyrus Group includes about seven important vectors of forest malaria, plus at least a dozen species of no known medical importance, with differential specific distributions collectively spanning > 5000 km from India to the Philippines.


Sujet(s)
Anopheles/classification , Animaux , Anopheles/anatomie et histologie , Femelle , Vecteurs insectes , Larve/anatomie et histologie , Mâle
13.
Acta Virol ; 48(1): 9-14, 2004.
Article de Anglais | MEDLINE | ID: mdl-15230469

RÉSUMÉ

This study reports on molecular analysis of a Measles virus (MV) isolate from a patient who was infected in Japan but showed symptoms after arriving to Brazil. This patient had typical clinical measles infection symptoms: fever, rash, cough and coryza. After isolating the virus in B95a cells, a fragment of the nucleoprotein (N) gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and subjected to direct nucleotide sequencing. The sequence data showed that the MV isolate of concern is of the D5 genotype.


Sujet(s)
Virus de la rougeole/génétique , Rougeole/épidémiologie , Brésil , Génotype , Humains , Nourrisson , Japon/épidémiologie , Rougeole/virologie , Virus de la rougeole/classification , Virus de la rougeole/isolement et purification , Nucléoprotéines/analyse , Nucléoprotéines/génétique , Phylogenèse , Réaction de polymérisation en chaîne , ARN viral/analyse
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