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1.
Parasitol Res ; 120(5): 1571-1582, 2021 May.
Article de Anglais | MEDLINE | ID: mdl-33852067

RÉSUMÉ

Genus and species of phlebotomine sand flies have been recorded and described in caves in Brazil, but no study has provided the food source used by sand flies in these environments. Herein, we identified the blood source used by sand fly species in caves located at "Quadrilátero Ferrífero" (QF), Minas Gerais state. Specimens were manually collected near or on anurans inside ferruginous caves in Serra do Gandarela National Park and Serra do Rola Moça State Park. Males and females were placed in vials with 70% alcohol and stored at -10°C. Females engorged, after specific identification, had DNA extracted and followed for PCR amplification using specific primers. Sequencing was analyzed in the GenBank and Barcode of Life. A total of 198 specimens were collected (107 females and 91 males), all of them belonging to species Sciopemyia aff. microps (88.89%), Sciopemyia sordellii (10.61%), or Martinsmyia oliveirai (0.50%). When it comes to the females, 89 were S. aff. microps and 18 S. sordellii. Nineteen engorged females of S. aff. microps were analyzed and most of them (n=18) presented blood from Bokermannohyla martinsi and one contained blood from Scinax fuscovarius. The blood present in engorged females of S. sordellii (n=4) was from B. martinsi. Sciopemyia genus specimens are commonly found in collections carried out inside natural caves, but this was the first study to prove that females of this genus feed on cold-blooded animals in nature. HIGHLIGHTS: • Here we proved that sand flies feed in cold-blooded animals in in Brazilian caves. • Females of the Sciopemyia genus were for the first time found feeding in natural habitats. • Anurans of the family Hylidae were identified as source by molecular analyzes. • Insect bloodmeal identification can help assessing the fauna in several biomes. • This is the first record of S. aff. microps in caves of Brazil.


Sujet(s)
Anura/parasitologie , Phlebotomus/classification , Phlebotomus/physiologie , Animaux , Brésil , ADN/génétique , Comportement alimentaire , Femelle , Aliments , Mâle , Parcs de loisirs , Réaction de polymérisation en chaîne
2.
Acta Trop ; 216: 105831, 2021 Apr.
Article de Anglais | MEDLINE | ID: mdl-33465351

RÉSUMÉ

Phlebotomine sand flies can transmit several species of the genus Leishmania, that cause leishmaniasis, a serious neglected tropical disease worldwide. Although Mexico is an endemic country for the disease, studies on the biology, ecology, and the identification of blood meal sources of phlebotomine sand flies in some states remain unexplored. For this reason, this study aimed to evaluate the species diversity of sand flies, and identify their blood meal sources in the Biosphere Reserve Los Tuxtlas, Veracruz, an area with a high prevalence of Leishmania infantum. The cumulative sampling effort of sand flies covered 300 trap-nights between March 2011 and May 2013. For estimating species diversity, we calculated the species richness (q = 0), the diversity of the species (q = 1) and the dominant species (q = 2). To identify the blood meal sources, we amplified and sequenced a fragment of ≈400 bp of the vertebrate Cytb gene. A total of 951 specimens belonging to 15 species were collected. Psathyromyia aclydifera and Psychodopygus panamensis were the most abundant species. We were able to identify seven terrestrial vertebrate species, among which human beings were the most common source of the blood meal. In this study, relevant information on the structure of sand fly populations and their blood meal sources was obtained, providing basic and important information about the interactions between sand flies, hosts and Leishmania species.


Sujet(s)
Vecteurs insectes/classification , Leishmania infantum , Leishmaniose viscérale/transmission , Phlebotomus/classification , Animaux , Femelle , Humains , Leishmania infantum/génétique , Mexique
3.
Acta Trop ; 201: 105220, 2020 Jan.
Article de Anglais | MEDLINE | ID: mdl-31618609

RÉSUMÉ

Mexico has great diversity of phlebotomine sand flies related to cases of leishmaniasis, yet few studies have dressed the molecular taxonomy of these sand fly species. The use of the cytochrome oxidase subunit 1 (COI) gene, as a DNA Barcode has facilitated the molecular identification of sand flies species worldwide. We use the DNA barcode as a useful tool for the identification of phlebotomine sand flies of the natural reserve Los Tuxtlas from Veracruz, México. A fragment of 536 bp of the COI gene was obtained from 36 individuals belonging to eight species of five genera (Dampfomyia, Lutzomyia, Psathyromyia, Psychodopygus and Brumptomyia) with coverage between 92-100%, and found similarities ranging from 93-98% with other New World phlebotomine sand flies. The NJ dendogram grouped sand flies into eight clusters according to identified species, supported by bootstrap of 97%-100%. In conclusion, all phlebotomine sand flies were correctly identified and agree with the morphological identification, also could separate genetics the isomorphic females of the genus Brumptomyia.


Sujet(s)
Codage à barres de l'ADN pour la taxonomie , Vecteurs de maladies/classification , Complexe IV de la chaîne respiratoire/génétique , Leishmaniose/génétique , Phlebotomus/classification , Phlebotomus/génétique , Animaux , Brésil , Femelle , Mexique
4.
Med Vet Entomol ; 31(4): 392-401, 2017 12.
Article de Anglais | MEDLINE | ID: mdl-28815634

RÉSUMÉ

The aims of the study were to (a) investigate the effect of trapping methods on alpha diversity; and (b) enhance the knowledge of the sandfly assemblage in the state of Quintana Roo. Field work was undertaken in a tropical forest of southern Mexico from August 2013 to July 2014. Sampling was conducted monthly during three consecutive nights. For each trapping night, 12 different types of trap were operated from 18.00 to 24.00 hours in four transects. Measures of alpha community diversity were based on the quantification of the number of species (Chao 2, Jackknife 2, Clench's equation, Margalef's index) and the community structure, as well as the dominance (Simpson and Berger-Parker indexes) and evenness (Shannon's entropy index, true diversity of the Jost and Pielou index). With a total sampling effort of 1728 night-traps, 16 101 phlebotomine sandflies were collected; they represented two genera and 13 species. Diversity estimates of 100% (Chao 2 and Clench's equation) and 85% (Jackknife 2) of potential species in the study area were calculated. Shannon traps and CDC light traps indicated the largest number of species, but only Shannon traps showed the greatest abundance. This inventory of sandflies is an important activity to enhance our knowledge of sandfly assemblages and guilds. The ultimate goal of studying alpha diversity in sandflies would be to have a better understanding of the population dynamics and all complex networks of interactions that may, in turn, be associated with the epidemiology of the disease.


Sujet(s)
Biodiversité , Entomologie/méthodes , Lutte contre les insectes/méthodes , Psychodidae/classification , Animaux , Mexique , Phlebotomus/classification , Dynamique des populations
5.
J Med Entomol ; 54(2): 450-459, 2017 03 01.
Article de Anglais | MEDLINE | ID: mdl-28011727

RÉSUMÉ

Phlebotomines (Diptera: Psychodidae) are vectors of several etiological agents of human and animal diseases, including protozoans of the gender Leishmania. Precarious socioeconomic conditions and uncontrolled population growth directly influence the transmission risk of parasites and the urbanization of vector species, previously restricted to wild environments. The Marajó Archipelago is considered a high incidence area of leishmaniasis in the Brazilian Amazon. However, it is poorly studied. The aim of this study was to assess the adaptation processes of phlebotomine species to anthropized environments in this region. For this purpose, the phlebotomine fauna was compared between three municipalities of the Marajó Archipelago: Anajás, Portel, and São Sebastião da Boa Vista. To survey the phlebotomine fauna, CDC (Center for Disease Control) light traps were installed in the wild areas and in the intra and peridomiciliary areas of rural and urban environments. The environments studied presented a diversified phlebotomine fauna, with higher richness in the wild environment (15 species), followed by the rural (seven species), and finally, the urban environment (three species). A migration of wild fauna to the adjacent anthropized areas (rural environment) and to urban areas was observed, evidencing the adaptation process of this vector to anthropized environments in the studied region. Thus, our study evidenced that the disorganized human occupation and utilization of the landscape might cause the invasion of urban areas by wild populations of phlebotomines, in this way enabling the settlement of urban leishmaniasis transmission cycles.


Sujet(s)
Vecteurs insectes/physiologie , Leishmaniose viscérale/transmission , Phlebotomus/physiologie , Adaptation physiologique , Migration animale , Animaux , Brésil , Environnement , Vecteurs insectes/parasitologie , Leishmania/physiologie , Leishmaniose viscérale/parasitologie , Phlebotomus/classification , Phlebotomus/parasitologie , Densité de population
6.
Mem. Inst. Oswaldo Cruz ; 111(8): 495-500, Aug. 2016. tab, graf
Article de Anglais | LILACS | ID: lil-789003

RÉSUMÉ

Leishmaniasis is a vector-borne disease that is transmitted by sandflies and caused by obligate intracellular protozoa of the genus Leishmania. In the present study, we carried out a screening on the experimental infection of Phlebotomus pernioucus by bioluminescent Leishmania infantum using murine model and artificial feeder. We developed a real-time polymerase chain reaction (RT-PCR)-based method to determine individually the number of Leishmania promastigotes fed by infected flies. Among 1840 new emerged female sand flies, 428 were fed on the infected mice. After their death, they were analysed individually by RT-PCR. Our results demonstrated just a single Leishmania positive female at sixth day post meal. A total of 1070 female sand flies were exposed in contact with artificial feeder containing the human blood with two different quantities of Leishmania parasites: 2.106/mL and 1.107/mL. A blood meal including 1.107/mL LUC-promastigotes was proposed to 270 females and 75 (28%) flies were engorged. Among them, 44 (59%) were positive by RT-PCR analysis, with a relative average of 50551 Leishmania parasites. In case of blood feeding of females with 2.106/mL promastigotes, 57 out of 800 (7%) females succeed to feed from artificial feeder which 22 (39%) were positive with a relative average of 6487 parasites.


Sujet(s)
Animaux , Femelle , Vecteurs insectes/parasitologie , Leishmania infantum/physiologie , Phlebotomus/parasitologie , Vecteurs insectes/classification , Leishmania infantum/croissance et développement , Mesures de luminescence , Souris , Souris de lignée BALB C , Phlebotomus/classification , Réaction de polymérisation en chaine en temps réel
7.
Mem Inst Oswaldo Cruz ; 111(8): 495-500, 2016 Jul 18.
Article de Anglais | MEDLINE | ID: mdl-27439032

RÉSUMÉ

Leishmaniasis is a vector-borne disease that is transmitted by sandflies and caused by obligate intracellular protozoa of the genus Leishmania. In the present study, we carried out a screening on the experimental infection of Phlebotomus pernioucus by bioluminescent Leishmania infantum using murine model and artificial feeder. We developed a real-time polymerase chain reaction (RT-PCR)-based method to determine individually the number of Leishmania promastigotes fed by infected flies. Among 1840 new emerged female sand flies, 428 were fed on the infected mice. After their death, they were analysed individually by RT-PCR. Our results demonstrated just a single Leishmania positive female at sixth day post meal. A total of 1070 female sand flies were exposed in contact with artificial feeder containing the human blood with two different quantities of Leishmania parasites: 2.106/mL and 1.107/mL. A blood meal including 1.107/mL LUC-promastigotes was proposed to 270 females and 75 (28%) flies were engorged. Among them, 44 (59%) were positive by RT-PCR analysis, with a relative average of 50551 Leishmania parasites. In case of blood feeding of females with 2.106/mL promastigotes, 57 out of 800 (7%) females succeed to feed from artificial feeder which 22 (39%) were positive with a relative average of 6487 parasites.


Sujet(s)
Vecteurs insectes/parasitologie , Leishmania infantum/physiologie , Phlebotomus/parasitologie , Animaux , Femelle , Vecteurs insectes/classification , Leishmania infantum/croissance et développement , Mesures de luminescence , Souris , Souris de lignée BALB C , Phlebotomus/classification , Réaction de polymérisation en chaine en temps réel
8.
Zootaxa ; 4105(5): 455-82, 2016 Apr 25.
Article de Anglais | MEDLINE | ID: mdl-27394791

RÉSUMÉ

The egg exochorion, larval instars and pupa of the phlebotomine sand fly Micropygomyia (Coquillettimyia) chiapanensis (Dampf) are described and illustrated based on specimens collected in the locality of Farallón, municipality of Actopan, Veracruz, Mexico. Morphology of fourth instar larval mouthparts, particularly the incisor lobe and molar lobe shape of mandible, could be important for species identification of immature Phlebotominae. In this work is compared the pupal chaetotaxy of Mi. chiapanensis with other species previously described. The fourth instar larva of Mi. chiapanensis is compared with other species of this genus, the most important differentiating characters being the size, shape and position of the abdominal dorsal internal seta.


Sujet(s)
Larve/croissance et développement , Phlebotomus/croissance et développement , Pupe/croissance et développement , Répartition des animaux , Structures anatomiques de l'animal/anatomie et histologie , Structures anatomiques de l'animal/croissance et développement , Animaux , Mensurations corporelles , Femelle , Larve/anatomie et histologie , Larve/classification , Mâle , Mexique , Taille d'organe , Phlebotomus/anatomie et histologie , Phlebotomus/classification , Pupe/anatomie et histologie , Pupe/classification
9.
Acta Trop ; 159: 125-31, 2016 Jul.
Article de Anglais | MEDLINE | ID: mdl-26992298

RÉSUMÉ

Identification of the species of phlebotomine sand flies present in each focus of leishmaniasis is necessary to incriminate vectors and implement vector control strategies. Although the cytochrome oxidase I (COI) gene has been proposed as a barcode for the identification of animal species, less than 20% of New World phlebotomines have been characterized to date. In this study DNA barcoding was used to identify phlebotomine species of the mixed leishmaniasis focus in the Colombian Caribbean by means of three evolutionary models: Kimura's two parameter (K2P) nucleotide substitution model, that of (Tamura and Nei, 1993) (TN93) and proportional sequence divergence (p-distances). A 681bp sequence of the COI gene was obtained from 66 individuals belonging to 19 species of the genus Lutzomyia (Lu. abonnenci, Lu. atroclavata, Lu. bicolor, Lu. carpenteri, Lu. cayennensis cayennensis, Lu. dubitans, Lu. evansi, Lu. gomezi, Lu. gorbitzi, Lu. longipalpis, Lu. micropyga, Lu. migonei, Lu. panamensis, Lu. (Psathyromyia) sp., Lu. rangeliana, Lu. serrana, Lu. shannoni, Lu. trinidadensis and Lu. venezuelensis) and one of Brumptomyia (B. mesai). The genetic divergence values for TN93 among individuals of the same species fluctuated up to 3.2% (vs. 2.9% for K2P and 2.8% for p-distances), while the values between species ranged from 8.8-43.7% (vs. 6.8-19.6% for K2P and 6.6-17.4% for p-distances). A dendrogram constructed by means of the Neighbor-Joining method grouped phlebotomines into 20 clusters according to species, with bootstrap values of up to 100% in those with more than one individual. However, loss of the phylogenetic signal of the gene COI was observed at the supraspecific level as a consequence of substitutional saturation. In conclusion, irrespective of the evolutionary model selected, all phlebotomines were correctly assigned to species, showing 100% concordance with morphological identification.


Sujet(s)
Codage à barres de l'ADN pour la taxonomie , Leishmaniose/parasitologie , Phlebotomus/classification , Phlebotomus/génétique , Animaux , Caraïbe , Colombie , Vecteurs de maladies , Variation génétique , Humains , Leishmaniose/transmission , Données de séquences moléculaires , Phylogenèse
10.
Acta Trop ; 153: 86-92, 2016 Jan.
Article de Anglais | MEDLINE | ID: mdl-26464046

RÉSUMÉ

Identification of the bloodmeal sources of phlebotomine sand flies is fundamental to determining which species are anthropophilic and understanding the transmission of Leishmania parasites in natural epidemiological settings. The objective of this study was to identify sand fly bloodmeals in the mixed leishmaniasis focus of the department of Sucre, northern Colombia. In all 141 engorged female sand flies were analyzed, after being captured in intradomiciliary, peridomiciliary and extradomiciliary habitats with Shannon and CDC traps and by active searching in diurnal resting sites. Bloodmeals were identified by sequencing and analysis of a 358bp fragment of the mitochondrial gene Cytochrome b (CYB) and a 330bp fragment of the nuclear gene prepronociceptin (PNOC). Using both genes 105 vertebrate bloodmeals were identified, with an efficiency of 72% for CYB but only 7% for PNOC. Ten species of vertebrates were identified as providing bloodmeal sources for 8 sand fly species: Homo sapiens (Lutzomyia evansi, Lutzomyia panamensis, Lutzomyia micropyga, Lutzomyia shannoni and Lutzomyia atroclavata), Equus caballus (L. evansi, L. panamensis and Lutzomyia cayennensis cayennensis), Equus asinus (L. evansi and L. panamensis), Bos taurus (L. evansi, L. panamensis and L. c. cayennensis), Tamandua mexicana (L. shannoni and Lutzomyia trinidadensis), Proechimys guyanensis (L. evansi, L. panamensis and L. c. cayennensis), Mabuya sp. (Lutzomyia micropyga), Anolissp. (L. micropyga), Sus scrofa (L. evansi and Lutzomyia gomezi) and Gallus gallus (L. evansi). Cattle, donkeys, humans and pigs were significantly more important than other animals (P=0.0001) as hosts of L. evansi, this being the most abundant sand fly species. The five Lutzomyia species in which blood samples of human origin were detected included L. micropyga and L. atroclavata, constituting the first evidence of anthropophily in both species.


Sujet(s)
Sang/parasitologie , Vecteurs insectes/classification , Leishmaniose/transmission , Phlebotomus/classification , Vertébrés/parasitologie , Animaux , Bovins/parasitologie , Colombie , Femelle , Equus caballus/parasitologie , Humains/parasitologie , Leishmania , Suidae/parasitologie
11.
Rev Inst Med Trop Sao Paulo ; 57(3): 233-8, 2015.
Article de Anglais | MEDLINE | ID: mdl-26200964

RÉSUMÉ

The aim of this study was to identify behavioral aspects of the sandfly fauna of a fishing tourism area in the municipality of Bonito (MS). Monthly captures were undertaken from December 2009 to November 2010, using automatic CDC type light traps, from 18h00 to 06h00, in a forested area, a savannah area, peridomiciles and animal shelters near peridomiciliary areas. Nyssomyia whitmani was the most frequent out of a total of 6,699 specimens collected, belonging to 16 species, followed by Psathyromyia bigeniculata and Lutzomyia longipalpis, found in all the environments investigated, though in their greatest numbers in the animal shelters. Ny. whitmani exhibited its highest frequencies during the dry months, coincident with the fishing season, when the risk of transmission of cutaneous leishmaniasis for tourists and inhabitants increases. Noteworthy was the finding of two species naturally infected by flagellates: Ny. whitmani and Pa. bigeniculata. The local population and visiting tourists should be warned of the threat posed by leishmaniasis and the health authorities alerted to the need for adopting environmental sanitary measures, especially regarding such animal shelters as they seem to provide favorable conditions to the proliferation, maintenance and breeding opportunities of phlebotomines.


Sujet(s)
Pêcheries , Vecteurs insectes/classification , Phlebotomus/classification , Animaux , Brésil , Humains , Leishmaniose cutanée/transmission , Densité de population , Saisons
12.
Rev. Inst. Med. Trop. Säo Paulo ; Rev. Inst. Med. Trop. Säo Paulo;57(3): 233-238, May-Jun/2015. tab, graf
Article de Anglais | LILACS | ID: lil-752596

RÉSUMÉ

The aim of this study was to identify behavioral aspects of the sandfly fauna of a fishing tourism area in the municipality of Bonito (MS). Monthly captures were undertaken from December 2009 to November 2010, using automatic CDC type light traps, from 18h00 to 06h00, in a forested area, a savannah area, peridomiciles and animal shelters near peridomiciliary areas. Nyssomyia whitmani was the most frequent out of a total of 6,699 specimens collected, belonging to 16 species, followed by Psathyromyia bigeniculata and Lutzomyia longipalpis, found in all the environments investigated, though in their greatest numbers in the animal shelters. Ny. whitmani exhibited its highest frequencies during the dry months, coincident with the fishing season, when the risk of transmission of cutaneous leishmaniasis for tourists and inhabitants increases. Noteworthy was the finding of two species naturally infected by flagellates: Ny. whitmani and Pa. bigeniculata. The local population and visiting tourists should be warned of the threat posed by leishmaniasis and the health authorities alerted to the need for adopting environmental sanitary measures, especially regarding such animal shelters as they seem to provide favorable conditions to the proliferation, maintenance and breeding opportunities of phlebotomines.


O objetivo deste estudo foi identificar aspectos do comportamento da fauna flebotomínea de área de turismo pesqueiro localizada no município de Bonito (MS). Foram realizadas capturas mensais no período de dezembro de 2009 a novembro de 2010, utilizando armadilhas luminosas automáticas do tipo CDC das 18:00h às 6:00h, em matas, área de cerrado, peridomicílios e abrigos de animais próximos a áreas peridomiciliares. De um total de 6.699 espécimes coletados, pertencentes a 16 espécies, Nyssomyia whitmani foi a mais frequente, seguida de Psathyromyia bigeniculata e Lutzomyia longipalpis, encontradas em todos os tipos de ambientes, porém com maior expressão em abrigos de animais. Ny. whitmani apresentou frequências mais elevadas nos meses mais secos, coincidentes com a estação da pesca, o que eleva o risco de transmissão da leishmaniose tegumentar a turistas e moradores da área. Importante ressaltar o encontro de duas espécies naturalmente infectadas por flagelados: Ny. whitmani e Pa. bigeniculata. A população local e turistas devem ser advertidos da ameaça que representam as leishmanioses e as autoridades de saúde alertadas para adoção de medidas de saneamento ambiental, principalmente com relação aos abrigos de animais, que parecem fornecer condições favoráveis para a proliferação, manutenção e reprodução de flebotomíneos.


Sujet(s)
Animaux , Humains , Pêcheries , Vecteurs insectes/classification , Phlebotomus/classification , Brésil , Leishmaniose cutanée/transmission , Densité de population , Saisons
13.
Mem. Inst. Oswaldo Cruz ; 110(4): 551-559, 09/06/2015. tab, graf
Article de Anglais | LILACS | ID: lil-748859

RÉSUMÉ

This study updates the geographic distributions of phlebotomine species in Central-West Brazil and analyses the climatic factors associated with their occurrence. The data were obtained from the entomology services of the state departments of health in Central-West Brazil, scientific collections and a literature review of articles from 1962-2014. Ecological niche models were produced for sandfly species with more than 20 occurrences using the Maxent algorithm and eight climate variables. In all, 2,803 phlebotomine records for 127 species were analysed. Nyssomyia whitmani, Evandromyia lenti and Lutzomyia longipalpis were the species with the greatest number of records and were present in all the biomes in Central-West Brazil. The models, which were produced for 34 species, indicated that the Cerrado areas in the central and western regions of Central-West Brazil were climatically more suitable to sandflies. The variables with the greatest influence on the models were the temperature in the coldest months and the temperature seasonality. The results show that phlebotomine species in Central-West Brazil have different geographical distribution patterns and that climate conditions in essentially the entire region favour the occurrence of at least one Leishmania vector species, highlighting the need to maintain or intensify vector control and surveillance strategies.


Sujet(s)
Animaux , Vecteurs insectes/classification , Phlebotomus/classification , Répartition des animaux , Brésil , Climat , Leishmaniose/transmission , Densité de population , Saisons
14.
Mem Inst Oswaldo Cruz ; 110(4): 551-9, 2015 Jun.
Article de Anglais | MEDLINE | ID: mdl-26018450

RÉSUMÉ

This study updates the geographic distributions of phlebotomine species in Central-West Brazil and analyses the climatic factors associated with their occurrence. The data were obtained from the entomology services of the state departments of health in Central-West Brazil, scientific collections and a literature review of articles from 1962-2014. Ecological niche models were produced for sandfly species with more than 20 occurrences using the Maxent algorithm and eight climate variables. In all, 2,803 phlebotomine records for 127 species were analysed. Nyssomyia whitmani, Evandromyia lenti and Lutzomyia longipalpis were the species with the greatest number of records and were present in all the biomes in Central-West Brazil. The models, which were produced for 34 species, indicated that the Cerrado areas in the central and western regions of Central-West Brazil were climatically more suitable to sandflies. The variables with the greatest influence on the models were the temperature in the coldest months and the temperature seasonality. The results show that phlebotomine species in Central-West Brazil have different geographical distribution patterns and that climate conditions in essentially the entire region favour the occurrence of at least one Leishmania vector species, highlighting the need to maintain or intensify vector control and surveillance strategies.


Sujet(s)
Vecteurs insectes/classification , Phlebotomus/classification , Répartition des animaux , Animaux , Brésil , Climat , Leishmaniose/transmission , Densité de population , Saisons
15.
Acta Trop ; 145: 45-51, 2015 May.
Article de Anglais | MEDLINE | ID: mdl-25697864

RÉSUMÉ

Phlebotomine sand flies are the only proven vectors of leishmaniases, a group of human and animal diseases. Accurate knowledge of sand fly species identification is essential in understanding the epidemiology of leishmaniasis and vector control in endemic areas. Classical identification of sand fly species based on morphological characteristics often remains difficult and requires taxonomic expertise. Here, we generated DNA barcodes of the cytochrome c oxidase subunit 1 (COI) gene using 159 adult specimens morphologically identified to be 19 species of sand flies, belonging to 6 subgenera/species groups circulating in Peru, including the vector species. Neighbor-joining (NJ) analysis based on Kimura 2-Parameter genetic distances formed non-overlapping clusters for all species. The levels of intraspecific genetic divergence ranged from 0 to 5.96%, whereas interspecific genetic divergence among different species ranged from 8.39 to 19.08%. The generated COI barcodes could discriminate between all the sand fly taxa. Besides its success in separating known species, we found that DNA barcoding is useful in revealing population differentiation and cryptic diversity, and thus promises to be a valuable tool for epidemiological studies of leishmaniasis.


Sujet(s)
Codage à barres de l'ADN pour la taxonomie , Leishmaniose/parasitologie , Phlebotomus/classification , Phlebotomus/génétique , Animaux , Vecteurs de maladies , Complexe IV de la chaîne respiratoire/génétique , Maladies endémiques , Humains , Leishmaniose/transmission , Données de séquences moléculaires , Pérou , Phlebotomus/enzymologie
16.
Zootaxa ; 3887(3): 251-97, 2014 Nov 25.
Article de Anglais | MEDLINE | ID: mdl-25543934

RÉSUMÉ

All immature stages of the phlebotomine sandfly Dampfomyia (Coromyia) beltrani (Vargas & Díaz-Nájera) [= Lutzomyia (Coromyia) beltrani, sensu Young & Duncan 1994] are described and illustrated based on reared specimens from founder females collected from the type-locality in Veracruz, Mexico. These represent the first description of egg, and the third of larva instars and pupa of a species of the subgenus Coromyia, only preceded by Da. vespertilionis (Fairchild & Hertig) and Da. isovespertilionis (Fairchild & Hertig). Some morphological nomenclature clarifications are suggested toward the standardization of immature descriptions, which, in turn, would allow detection of homologies for future integration of these developmental stages characters into a phylogenetic analyses.


Sujet(s)
Phlebotomus/anatomie et histologie , Animaux , Femelle , Larve/anatomie et histologie , Mâle , Mexique , Microscopie électronique à balayage , Ovule/ultrastructure , Phlebotomus/classification , Phlebotomus/croissance et développement , Pupe/anatomie et histologie , Terminologie comme sujet
17.
Rev Soc Bras Med Trop ; 47(1): 57-62, 2014.
Article de Anglais | MEDLINE | ID: mdl-24603738

RÉSUMÉ

INTRODUCTION: In past decades, leishmaniasis burden has been low across Egypt; however, changing environment and land use has placed several parts of the country at risk. As a consequence, leishmaniasis has become a particularly difficult health problem, both for local inhabitants and for multinational military personnel. METHODS: To evaluate coarse-resolution aspects of the ecology of leishmaniasis transmission, collection records for sandflies and Leishmania species were obtained from diverse sources. To characterize environmental variation across the country, we used multitemporal Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) for 2005-2011. Ecological niche models were generated using MaxEnt, and results were analyzed using background similarity tests to assess whether associations among vectors and parasites (i.e., niche similarity) can be detected across broad geographic regions. RESULTS: We found niche similarity only between one vector species and its corresponding parasite species (i.e., Phlebotomus papatasi with Leishmania major), suggesting that geographic ranges of zoonotic cutaneous leishmaniasis and its potential vector may overlap, but under distinct environmental associations. Other associations (e.g., P. sergenti with L. major) were not supported. Mapping suitable areas for each species suggested that northeastern Egypt is particularly at risk because both parasites have potential to circulate. CONCLUSIONS: Ecological niche modeling approaches can be used as a first-pass assessment of vector-parasite interactions, offering useful insights into constraints on the geography of transmission patterns of leishmaniasis.


Sujet(s)
Vecteurs insectes/parasitologie , Leishmaniose/transmission , Phlebotomus/parasitologie , Animaux , Écosystème , Égypte , Géographie médicale , Humains , Vecteurs insectes/classification , Leishmaniose/parasitologie , Phlebotomus/classification
18.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;47(1): 57-62, Jan-Feb/2014. graf
Article de Anglais | LILACS | ID: lil-703153

RÉSUMÉ

Introduction: In past decades, leishmaniasis burden has been low across Egypt; however, changing environment and land use has placed several parts of the country at risk. As a consequence, leishmaniasis has become a particularly difficult health problem, both for local inhabitants and for multinational military personnel. Methods: To evaluate coarse-resolution aspects of the ecology of leishmaniasis transmission, collection records for sandflies and Leishmania species were obtained from diverse sources. To characterize environmental variation across the country, we used multitemporal Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) for 2005-2011. Ecological niche models were generated using MaxEnt, and results were analyzed using background similarity tests to assess whether associations among vectors and parasites (i.e., niche similarity) can be detected across broad geographic regions. Results: We found niche similarity only between one vector species and its corresponding parasite species (i.e., Phlebotomus papatasi with Leishmania major), suggesting that geographic ranges of zoonotic cutaneous leishmaniasis and its potential vector may overlap, but under distinct environmental associations. Other associations (e.g., P. sergenti with L. major) were not supported. Mapping suitable areas for each species suggested that northeastern Egypt is particularly at risk because both parasites have potential to circulate. Conclusions: Ecological niche modeling approaches can be used as a first-pass assessment of vector-parasite interactions, offering useful insights into constraints on the geography of transmission patterns of leishmaniasis. .


Sujet(s)
Animaux , Humains , Vecteurs insectes/parasitologie , Leishmaniose/transmission , Phlebotomus/parasitologie , Écosystème , Égypte , Géographie médicale , Vecteurs insectes/classification , Leishmaniose/parasitologie , Phlebotomus/classification
19.
Mem. Inst. Oswaldo Cruz ; 108(7): 845-849, 1jan. 2013. graf
Article de Anglais | LILACS | ID: lil-696018

RÉSUMÉ

During a research project aimed at the study of the Culicinae fauna of Gabon and carried out in the National Park of La Lopé, we captured an unknown sandfly male specimen (genus Phlebotomus) by CDC miniature light trap belonging to a new species for Science. Furthermore, the originality of his genitalia does not allow us to include this species in one of the existing subgenus, thus in this paper we propose the creation of a new subgenus, as Phlebotomus (Legeromyia) multihamatus sp. nov., subg. nov. described from the National Park of La Lopé, through one male captured with CDC miniature light trap. A new species and a new subgenus of sandfly is characterised by a short style with three spines, a paramere wearing a basal hook as well as a basal pouch and the absence of basal lobe on the coxite. The originality of the genitalia of the male gives way to discussion about potential primary homologies between P. multihamatus sp. nov. and Phlebotomus (Abonnencius) fortunatarum, Phlebotomus (Anaphlebotomus) stantoni and Phlebotomus (Euphlebotomus) argentipes, which should be verified for future studies. The discovery of this new species in Gabon must encourage the study of sandflies in this country.


Sujet(s)
Animaux , Mâle , Phlebotomus/anatomie et histologie , Phlebotomus/classification , Gabon , Spécificité d'espèce
20.
Mem Inst Oswaldo Cruz ; 108(8): 1065-7, 2013 Dec.
Article de Anglais | MEDLINE | ID: mdl-24141963

RÉSUMÉ

The breeding habitat of sandflies is a little studied and poorly understood phenomenon. More importantly, oviposition behaviour is a largely neglected aspect of sandfly biology and this knowledge gap further undermines our understanding of the biology of sandflies. Pheromones released by the eggs play an important role in identifying good sites for oviposition by female insects. Several recent studies have examined the oviposition pheromone. The present study provides a preliminary report on the oviposition behaviour of Phlebotomus argentipes, the only vector of kala-azar (or visceral leishmaniasis) on the Indian sub-continent. Sandflies prefer to oviposit their eggs on surfaces that contain organic substances, especially substances with an odour of decaying animal products and the remains of conspecific eggs. The results presented here suggest that the odour released by the organic substances of old sandfly colony remains that contain dead flies, old unhatched eggs, larval food containing vertebrate faeces, frass and other organic matter serves as an attractant for the ovipositing females of P. argentipes and hence greatly increases the number of oviposited eggs compared to eggs deposited in controlled oviposition pots. This result will be helpful in maintaining an efficient colony of P. argentipes and may be a promising tool for monitoring and controlling the target insect as part of a synergistic approach.


Sujet(s)
Vecteurs insectes/anatomie et histologie , Oviposition/physiologie , Phéromones/physiologie , Phlebotomus/anatomie et histologie , Animaux , Femelle , Vecteurs insectes/classification , Vecteurs insectes/physiologie , Laboratoires , Mâle , Phlebotomus/classification , Phlebotomus/physiologie
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