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1.
J Vector Ecol ; 43(1): 168-178, 2018 06.
Article in English | MEDLINE | ID: mdl-29757525

ABSTRACT

In southeast Amazon, Lutzomyia (Nyssomyia) flaviscutellata is the incriminated vector of Leishmania (Leishmania) amazonensis, a causative agent of zoonotic cutaneous leishmaniasis (CL). The optimal methods for surveying Lu. flaviscutellata were investigated in the Bragança region, northeast Pará State, Brazil, selected for the presence of Le. amazonensis. The performances of modified Disney traps and CDC light traps were compared in four ecotopes within and around four village transects during the wet and dry seasons. The physiological age of female sand flies was estimated and natural infection by flagellates was evaluated by dissection. Disney traps were better for detecting the presence of Lu. flaviscutellata, while CDC traps performed well for detecting Lutzomyia (Nyssomyia) antunesi, suspected vector of Leishmania lindenbergi. The former was more abundant during the wet season, when female flies were naturally infected with Le. amazonensis. These findings identified the environments of local transmission. In order to improve surveys of Lu. flaviscutellata as part of integrated epidemiological surveillance of CL, our recommendations include focusing vector surveys with Disney traps on forest fragments where people work, during the seasonal peak of the vector. Further field studies are required to make model-based predictions of seasonal variations in the vectorial capacity of vector populations.


Subject(s)
Insect Vectors/parasitology , Insect Vectors/pathogenicity , Leishmaniasis, Cutaneous/transmission , Psychodidae/parasitology , Psychodidae/pathogenicity , Animals , Brazil , Entomology , Leishmania/pathogenicity , Leishmaniasis, Cutaneous/parasitology , Seasons
2.
Parasit Vectors ; 10(1): 157, 2017 Mar 24.
Article in English | MEDLINE | ID: mdl-28340594

ABSTRACT

BACKGROUND: Before 1996 the phlebotomine sand fly Lutzomyia neivai was usually treated as a synonym of the morphologically similar Lutzomyia intermedia, which has long been considered a vector of Leishmania braziliensis, the causative agent of much cutaneous leishmaniasis in South America. This report investigates the likely range changes of both sand fly species in response to a stabilisation climate change scenario (RCP4.5) and a high greenhouse gas emissions one (RCP8.5). METHODS: Ecological niche modelling was used to identify areas of South America with climates currently suitable for each species, and then the future distributions of these climates were predicted based on climate change scenarios. Compared with the previous ecological niche model of L. intermedia (sensu lato) produced using the GARP algorithm in 2003, the current investigation modelled the two species separately, making use of verified presence records and additional records after 2001. Also, the new ensemble approach employed ecological niche modelling algorithms (including Maximum Entropy, Random Forests and Support Vector Machines) that have been widely adopted since 2003 and perform better than GARP, as well as using a more recent climate change model (HadGEM2) considered to have better performance at higher resolution than the earlier one (HadCM2). RESULTS: Lutzomyia intermedia was shown to be the more tropical of the two species, with its climatic niche defined by higher annual mean temperatures and lower temperature seasonality, in contrast to the more subtropical L. neivai. These different latitudinal ranges explain the two species' predicted responses to climate change by 2050, with L. intermedia mostly contracting its range (except perhaps in northeast Brazil) and L. neivai mostly shifting its range southwards in Brazil and Argentina. This contradicts the findings of the 2003 report, which predicted more range expansion. The different findings can be explained by the improved data sets and modelling methods. CONCLUSIONS: Our findings indicate that climate change will not always lead to range expansion of disease vectors such as sand flies. Ecological niche models should be species specific, carefully selected and combined in an ensemble approach.


Subject(s)
Climate Change , Insect Vectors , Psychodidae/growth & development , Animals , Models, Theoretical , South America , Spatial Analysis , Species Specificity
3.
PLoS One ; 10(11): e0143282, 2015.
Article in English | MEDLINE | ID: mdl-26619186

ABSTRACT

Vector borne diseases are susceptible to climate change because distributions and densities of many vectors are climate driven. The Amazon region is endemic for cutaneous leishmaniasis and is predicted to be severely impacted by climate change. Recent records suggest that the distributions of Lutzomyia (Nyssomyia) flaviscutellata and the parasite it transmits, Leishmania (Leishmania) amazonensis, are expanding southward, possibly due to climate change, and sometimes associated with new human infection cases. We define the vector's climatic niche and explore future projections under climate change scenarios. Vector occurrence records were compiled from the literature, museum collections and Brazilian Health Departments. Six bioclimatic variables were used as predictors in six ecological niche model algorithms (BIOCLIM, DOMAIN, MaxEnt, GARP, logistic regression and Random Forest). Projections for 2050 used 17 general circulation models in two greenhouse gas representative concentration pathways: "stabilization" and "high increase". Ensemble models and consensus maps were produced by overlapping binary predictions. Final model outputs showed good performance and significance. The use of species absence data substantially improved model performance. Currently, L. flaviscutellata is widely distributed in the Amazon region, with records in the Atlantic Forest and savannah regions of Central Brazil. Future projections indicate expansion of the climatically suitable area for the vector in both scenarios, towards higher latitudes and elevations. L. flaviscutellata is likely to find increasingly suitable conditions for its expansion into areas where human population size and density are much larger than they are in its current locations. If environmental conditions change as predicted, the range of the vector is likely to expand to southeastern and central-southern Brazil, eastern Paraguay and further into the Amazonian areas of Bolivia, Peru, Ecuador, Colombia and Venezuela. These areas will only become endemic for L. amazonensis, however, if they have competent reservoir hosts and transmission dynamics matching those in the Amazon region.


Subject(s)
Animal Distribution , Climate Change , Ecosystem , Models, Statistical , Psychodidae/physiology , Animals , Disease Vectors , South America
4.
PLoS One ; 6(12): e27721, 2011.
Article in English | MEDLINE | ID: mdl-22163271

ABSTRACT

BACKGROUND: Although leishmaniases are regarded as serious public health issues in the State of Tocantins, as consequence of the impact of environmental changes, small advances in taxonomic and ecological studies of Phlebotominae fauna are taking place in this state. The present study aimed to improve the knowledge about the sand flies, as well as about the aspects of the bioecology of leishmaniases vectors from Porto Nacional, a city that was directly impacted by the construction of Luís Eduardo Magalhães Hydroelectric Plant (HEP-Lajeado). METHODOLOGY/PRINCIPAL FINDINGS: Sand flies were collected monthly using CDC light traps and Shannon traps for a period of 40 consecutive months, at different monitoring stations, where 7162 specimens were collected and 48 species were detected. Among the species found, 22 are first records in the state and seven are considered important vectors of leishmaniases. Lutzomyia longipalpis, the vector of American Visceral Leishmaniasis (AVL) showed higher frequency in urban compared to rural areas, and Nyssomyia whitmani, the vector of American Cutaneous Leishmaniasis (ACL), predominated in rural areas. The frequency and habits of sand fly vectors are discussed considering environmental characteristics and climatic factors. CONCLUSIONS/SIGNIFICANCE: The construction of dams requires a great amount of labor, therefore attracting people from elsewhere. Increased migration, without adequate structure, leads to bad living conditions in new and unplanned settlements. It also leads to deforestation associated with environmental impacts, which can facilitate the spread of leishmaniases. This study discusses the importance of Lu. longipalpis and Ny. whitmani on the transmission cycles of leishmaniases in Porto Nacional and the record of Bi. flaviscutellata in periurban area of the city.


Subject(s)
Leishmaniasis, Cutaneous/transmission , Leishmaniasis, Visceral/transmission , Psychodidae/physiology , Animals , Brazil , Cities , Environment , Environmental Monitoring , Female , Humans , Insect Vectors , Male , Models, Statistical , Population Density , Seasons
5.
Acta Trop ; 120(3): 273-5, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21939631

ABSTRACT

In order to determine natural Leishmania (Viannia) infection in Lutzomyia (Pintomyia) fischeri, a multiplex PCR methodology coupled to non-isotopic hybridization was adopted for the analysis of sand fly samples collected by CDC light traps in an endemic area of American Cutaneous Leishmaniasis (ACL) in the periurban region of the municipality of Porto Alegre, Rio Grande do Sul State, Brazil. We analyzed by PCR methodology 560 specimens of Lutzomyia (Pintomyia) fischeri (520 females and 40 males). The wild sand flies were grouped into 56 pools (52 females and 4 males) of 10 each, and positive results were detected in 2 of the 52 female pools, representing a minimum infection rate of 0.38% based on the presence of at least 1 infected insect in the pool. This result associated with some local evidence such as anthopophily, spatial distribution in accordance with the transmission area and human case incidence, suggests that L. (P.)fischeri may be considered as a secondary vector of ACL in the studied locality.


Subject(s)
Disease Vectors , Leishmania/isolation & purification , Leishmaniasis, Cutaneous/transmission , Psychodidae/parasitology , Animals , Brazil , DNA, Protozoan/genetics , Female , Male , Multiplex Polymerase Chain Reaction/methods
6.
J Biomed Biotechnol ; 2010: 439174, 2010.
Article in English | MEDLINE | ID: mdl-20011070

ABSTRACT

The interaction between Leishmania and sand flies has been demonstrated in many Old and New World species. Besides the morphological differentiation from procyclic to infective metacyclic promastigotes, the parasite undergoes biochemical transformations in its major surface lipophosphoglycan (LPG). An upregulation of beta-glucose residues was previously shown in the LPG repeat units from procyclic to metacyclic phase in Leishmania (Viannia) braziliensis, which has not been reported in any Leishmania species. LPG has been implicated as an adhesion molecule that mediates the interaction with the midgut epithelium of the sand fly in the Subgenus Leishmania. These adaptations were explored for the first time in a species from the Subgenus Viannia, L. (V.) braziliensis with its natural vectors Lutzomyia (Nyssomyia) intermedia and Lutzomyia (Nyssomyia) whitmani. Using two in vitro binding techniques, phosphoglycans (PGs) derived from procyclic and metacyclic parasites were able to bind to the insect midgut and inhibit L. braziliensis attachment. Interestingly, L. braziliensis procyclic parasite attachment was approximately 11-fold greater in the midgut of L. whitmani than in L. intermedia. The epidemiological relevance of L. whitmani as a vector of American Cutaneous Leishmaniasis (ACL) in Brazil is discussed.


Subject(s)
Leishmania braziliensis/pathogenicity , Psychodidae/parasitology , Animals , Digestive System/metabolism , Digestive System/parasitology , Glycosphingolipids/chemistry , Glycosphingolipids/isolation & purification , Glycosphingolipids/metabolism , Host-Parasite Interactions/physiology , Life Cycle Stages , Microscopy, Fluorescence
7.
J Med Entomol ; 46(5): 1125-30, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19769044

ABSTRACT

This no-choice, laboratory study focuses on the feeding of dried, ground, homogeneous powdered, unprocessed fruit and leaves of Azadirachta indica and Melia azedarach to Lutzomyia longipalpis larvae to determine the effects on their mortality and metamorphosis. A. indica and M. azedarach fruit and leaves significantly increased larval mortality in comparison to larvae fed the untreated, standard diet. A. indica fruit and leaves blocked the molting of the larvae to the fourth instar, resulting in them remaining as third instars until the end of the experiment. M. azedarach fruit also blocked the molting of larvae, which remained permanently in the fourth instar. Feeding M. azedarach leaves resulted in greater molt inhibition. All insects in this group stopped their development as second-instar larvae. No antifeedant effect was detected for any experimental treatment. The results indicate that nontoxic, unprocessed materials obtained from A. indica and M. azedarach are potent development inhibitors of L. longipalpis larvae.


Subject(s)
Azadirachta , Melia azedarach , Metamorphosis, Biological/drug effects , Plant Extracts/pharmacology , Psychodidae/drug effects , Animals , Fruit , Larva/drug effects , Larva/growth & development , Plant Leaves , Psychodidae/growth & development
8.
Am J Trop Med Hyg ; 80(4): 593-5, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19346382

ABSTRACT

To identify Lutzomyia (Nyssomyia) neivai naturally infected by Leishmania a multiplex polymerase chain reaction (PCR) was used for the analysis of 450 specimens (270 females, 180 males) collected in an endemic periurban area of cutaneous leishmaniasis in Porto Alegre, Brazil. Insects were grouped into pools of 10 and positive results were achieved in 3/27 Lu. (N.) neivai female pools. Infection by L. (Viannia) braziliensis was confirmed after hybridizing PCR products with a subgenus-specific biotinylated probe. Considering the detection of three positive pools with at least one infected insect in each, an infection rate of 1.1% was estimated. Our results associated with epidemiologic data suggest a potential ability of Lu. (N.) neivai in transmitting L. braziliensis in Porto Alegre, where the first notifications of autochthonous cutaneous leishmaniasis in humans occurred in 2002, with an increase in the number of cases in recent years possibly as a consequence of deforestation and agricultural activities in the area.


Subject(s)
Leishmania braziliensis/isolation & purification , Polymerase Chain Reaction/methods , Psychodidae/parasitology , Animals , Brazil , DNA, Protozoan/analysis , Demography , Female , Leishmania braziliensis/genetics , Male
9.
Cad Saude Publica ; 24(12): 2948-52, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19082287

ABSTRACT

The article discusses habits related to the vectorial competence of Lutzomyia longipalpis, along with evidence confirming the importance of this sand fly species in the epidemiological chain of visceral leishmaniasis in Brazil. A new epidemiological profile for visceral leishmaniasis is also postulated, associated with domestic environments and the role of Lu. longipalpis in this process, its sylvatic origin, and its capacity to adapt to a wide range of habitats. Another sand fly species, Lu. cruzi, is mentioned as a vector of visceral leishmaniasis in some municipalities in Central Brazil, based on studies in endemic areas of the country.


Subject(s)
Insect Vectors/physiology , Leishmaniasis, Visceral/transmission , Psychodidae/physiology , Animals , Brazil/epidemiology , Humans , Insect Vectors/classification , Leishmaniasis, Visceral/epidemiology , Psychodidae/classification , Urbanization
10.
Neotrop Entomol ; 37(5): 597-601, 2008.
Article in English | MEDLINE | ID: mdl-19061048

ABSTRACT

The bacterial community associated with the midgut of three Brazilian Lutzomyia longipalpis (Lutz & Neiva) populations, two from endemic areas for visceral leishmaniasis (Jacobina, Bahia State and São Luís, Maranhão State) and one from a non-endemic area (Lapinha Cave, Minas Gerais State), was identified. Five groups, 35 females each, from each population were separated; a total of 175 females per collecting area were analyzed. The species identification was based on molecular and traditional bacteriological methods. All bacteria were either affiliated to non-Enterobacteriaceae, such as Acinetobacter, Burkholderia, Flavimonas, Pseudomonas and Stenotrophomonas, or and to Enterobacteriaceae, such as Citrobacter, Enterobacter, Escherichia, Klebsiella, Serratia, Pantoea, Morganella and Weeksella. Stenotrophomonas was found to be associated with all three populations studied. In addition, Serratia spp., which are well documented as laboratory contaminant of insects, were detected only in the Jacobina population. We also discuss the impact of the colonization of insect gut by bacteria on the development and transmission of pathogens.


Subject(s)
Psychodidae/microbiology , Animals , Brazil
11.
Cad. saúde pública ; 24(12): 2948-2952, dez. 2008.
Article in English | LILACS | ID: lil-499786

ABSTRACT

The article discusses habits related to the vectorial competence of Lutzomyia longipalpis, along with evidence confirming the importance of this sand fly species in the epidemiological chain of visceral leishmaniasis in Brazil. A new epidemiological profile for visceral leishmaniasis is also postulated, associated with domestic environments and the role of Lu. longipalpis in this process, its sylvatic origin, and its capacity to adapt to a wide range of habitats. Another sand fly species, Lu. cruzi, is mentioned as a vector of visceral leishmaniasis in some municipalities in Central Brazil, based on studies in endemic areas of the country.


São apresentados os hábitos que condicionam a competência vetorial de Lutzomyia longipalpis e discutidas as evidências que confirmam a importância deste flebotomíneo na cadeia de transmissão da leishmaniose visceral no Brasil. Discute-se, também, o novo perfil epidemiológico da leishmaniose visceral, associado à ambientes urbanos, e o papel desempenhado por Lu. longipalpis neste processo, sua origem silvestre e capacidade de adaptação. É citado outro flebotomíneo, Lu. cruzi, como transmissor em alguns municípios da região central do Brasil, com base em estudos realizados em áreas endêmicas.


Subject(s)
Animals , Humans , Insect Vectors/physiology , Leishmaniasis, Visceral/transmission , Psychodidae/physiology , Brazil/epidemiology , Insect Vectors/classification , Leishmaniasis, Visceral/epidemiology , Psychodidae/classification , Urbanization
12.
Mem. Inst. Oswaldo Cruz ; 103(8): 760-766, Dec. 2008. graf, tab
Article in English | LILACS | ID: lil-502294

ABSTRACT

Studies were undertaken on the phlebotomines in the municipalities of Bujari, Xapuri and Rio Branco in the state of Acre. The abundance of species on the ground and in the tree canopy was estimated by Standardized Index of Species Abundance. Of the 52 species identified, Lutzomyia (N.) antunesi, Lutzomyia (N.) whitmani, Lutzomyia (P.) davisi, Lutzomyia migonei, Lutzomyia (N.) umbratilis, Lutzomyia (N.) flaviscutellata, Lutzomyia (T.) ubiqui-talis, Lutzomyia (P.) hirsuta hirsuta, Lutzomyia (P.) paraensis and Lutzomyia (P.) ayrozai are known to be vectors of Leishmania, the causative agent of American cutaneous leishmaniasis. Lutzomyia (T.) auraensis, Lu. (N.) antunesi, Lu. (N.) whitmani and Lu. (P.) davisi accounted for 66.95 percent of the specimens collected. Lu. (N.) whitmani was the most abundant species, followed by Lu. (N.) antunesi and Lu. (P.) davisi. Lu. (N.) antunesi was the most abundant species in the soil as well as in the canopy. Lu. (N.) umbratilis occurred in all three municipalities and was the fifth most abundant species in the Chico Mendes Municipal Park in Rio Branco. It was collected on both the ground level as well as in the canopy; however, it was more frequently collected in the tree canopy. The present study suggests the existence of three transmission cycles of Leishmania in Acre, including the transmission of Leishmania (V.) guyanensis by Lu. (N.) umbratilis south of the Amazon River.


Subject(s)
Animals , Female , Humans , Insect Vectors/classification , Psychodidae/classification , Brazil/epidemiology , Ecosystem , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/transmission , Population Density
13.
Neotrop. entomol ; 37(5): 597-601, Sept.-Oct. 2008. tab
Article in English | LILACS | ID: lil-498321

ABSTRACT

A flora bacteriana encontrada no intestino de populações brasileiras de Lutzomyia longipalpis (Lutz & Neiva) provenientes de duas áreas endêmicas para leishmaniose visceral (Jacobina, BA e São Luís, MA) e de uma área não endêmica (Gruta da Lapinha, MG) é descrita. Cinco grupos de 35 fêmeas de cada população foram separados, no total de 175 fêmeas analisadas por área de coleta. A identificação das espécies foi baseada em métodos moleculares e em métodos bacteriológicos tradicionais. As bactérias encontradas foram classificadas como pertencentes ao grupo das não-Enterobacteriaceae, como Acinetobacter, Burkholderia, Flavimonas, Pseudomonas, ou ao grupo das Enterobacteriaceae, como Stenotrophomonas, Citrobacter, Enterobacter, Escherichia, Klebsiella, Serratia, Pantoea, Morganella e Weeksella. Stenotrophomonas esteve presente nas três populações analisadas. Além disso, Serratia spp., grupo bem documentado como contaminante laboratorial de insetos, foi detectado apenas na população de Jacobina. O impacto da colonização do intestino de insetos por bactérias no desenvolvimento e transmissão de patógenos é discutido.


The bacterial community associated with the midgut of three Brazilian Lutzomyia longipalpis (Lutz & Neiva) populations, two from endemic areas for visceral leishmaniasis (Jacobina, Bahia State and São Luís, Maranhão State) and one from a non-endemic area (Lapinha Cave, Minas Gerais State), was identified. Five groups, 35 females each, from each population were separated; a total of 175 females per collecting area were analyzed. The species identification was based on molecular and traditional bacteriological methods. All bacteria were either affiliated to non-Enterobacteriaceae, such as Acinetobacter, Burkholderia, Flavimonas, Pseudomonas and Stenotrophomonas, or and to Enterobacteriaceae, such as Citrobacter, Enterobacter, Escherichia, Klebsiella, Serratia, Pantoea, Morganella and Weeksella. Stenotrophomonas was found to be associated with all three populations studied. In addition, Serratia spp., which are well documented as laboratory contaminant of insects, were detected only in the Jacobina population. We also discuss the impact of the colonization of insect gut by bacteria on the development and transmission of pathogens.


Subject(s)
Animals , Psychodidae/microbiology , Brazil
14.
Mem Inst Oswaldo Cruz ; 103(8): 760-7, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19148413

ABSTRACT

Studies were undertaken on the phlebotomines in the municipalities of Bujari, Xapuri and Rio Branco in the state of Acre. The abundance of species on the ground and in the tree canopy was estimated by Standardized Index of Species Abundance. Of the 52 species identified, Lutzomyia (N.) antunesi, Lutzomyia (N.) whitmani, Lutzomyia (P.) davisi, Lutzomyia migonei, Lutzomyia (N.) umbratilis, Lutzomyia (N.) flaviscutellata, Lutzomyia (T.) ubiqui-talis, Lutzomyia (P.) hirsuta hirsuta, Lutzomyia (P.) paraensis and Lutzomyia (P.) ayrozai are known to be vectors of Leishmania, the causative agent of American cutaneous leishmaniasis. Lutzomyia (T.) auraensis, Lu. (N.) antunesi, Lu. (N.) whitmani and Lu. (P.) davisi accounted for 66.95% of the specimens collected. Lu. (N.) whitmani was the most abundant species, followed by Lu. (N.) antunesi and Lu. (P.) davisi. Lu. (N.) antunesi was the most abundant species in the soil as well as in the canopy. Lu. (N.) umbratilis occurred in all three municipalities and was the fifth most abundant species in the Chico Mendes Municipal Park in Rio Branco. It was collected on both the ground level as well as in the canopy; however, it was more frequently collected in the tree canopy. The present study suggests the existence of three transmission cycles of Leishmania in Acre, including the transmission of Leishmania (V.) guyanensis by Lu. (N.) umbratilis south of the Amazon River.


Subject(s)
Insect Vectors/classification , Psychodidae/classification , Animals , Brazil/epidemiology , Ecosystem , Female , Humans , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/transmission , Population Density
15.
Mem Inst Oswaldo Cruz ; 102(2): 149-53, 2007 May.
Article in English | MEDLINE | ID: mdl-17426877

ABSTRACT

The aim of the present study, in view of the widespread geographical distribution of Lutzomyia (Nyssomyia) whitmani s.l. in Brazil, in close association with the regions of transmission of Leishmania (Viannia) braziliensis and L. (V.) shawi, is to investigate the distribution of this sand fly species and American cutaneous leishmaniasis (ACL) in relationship to vegetation and landscape ecology throughout Brazil. Thematic maps were elaborated by the MapInfo programme, giving information on the spatial distribution of L. whitmani s.l., in accordance with types of vegetation and foci of ACL. With regards to the known areas of transmission of ACL in Brazil, it is notable that L. (N.) whitmani s.l. occurs in most of them, where it has been implicated as a possible vector of L. (V.) braziliensis. The presence of L. whitmani s.l. has been registered in 26 states, the one exception being Santa Catarina; in some states such as Roraima, Acre, Tocantins, and Mato Grosso do Sul this sand fly species has been recorded in a large number of municipalities. L. whitmani s.l. has been found in association with a variety of vegetation types, including the Amazonian forest, savanna ("campos cerrados"), and northeastern savanna ("caatingas nordestinas" or "savana estépica").


Subject(s)
Insect Vectors/physiology , Leishmania braziliensis , Leishmaniasis, Cutaneous/epidemiology , Psychodidae/physiology , Animals , Brazil/epidemiology , Ecosystem , Geography , Humans , Insect Vectors/parasitology , Leishmaniasis, Cutaneous/transmission , Population Dynamics , Psychodidae/parasitology , Trees
16.
Cad Saude Publica ; 23(3): 725-30, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17334585

ABSTRACT

The sand fly fauna in Itatiaia National Park, Rio de Janeiro, Brazil, was investigated in different habitats ranging from sylvatic areas to those altered by human activity related to ecotourism, specifically identifying species that have been suggested as potential leishmaniasis vectors. Sand flies were captured from June 2002 to March 2004, using CDC light traps and Shannon traps. A total of 1,256 sand fly specimens were captured, from species belonging to genera Lutzomyia and Brumptomyia: Brumptomyia guimaraesi, B. troglodytes, Lutzomyia (Lutzomyia) amarali, L. lanei, L. migonei, L. sallesi, L. edwardsi, L. tupynambai, L. (Pintomyia) pessoai, L. (P.) bianchigalatie, L. rupicola, L. (Psathyromyia) shannoni, L. pascalei, L. (Psychodopygus) matosi, L. (P.) davisi, L. (P.) hirsuta hirsuta, L. (P.) ayrozai, L. peresi, L. monticola, and L. misionensis. Worthy of special attention were four species that are considered potential vectors for cutaneous leishmaniasis in Brazil: L. ayrozai, L. hirsuta hirsuta, L. migonei, and L. davisi, representing 19.19% of the specimens captured in this study.


Subject(s)
Ecosystem , Insect Vectors/classification , Leishmaniasis, Cutaneous/transmission , Psychodidae/classification , Animals , Brazil , Humans , Insect Vectors/physiology , Psychodidae/physiology , Species Specificity
17.
Mem. Inst. Oswaldo Cruz ; 102(2): 149-153, Mar. 2007.
Article in English | LILACS | ID: lil-447550

ABSTRACT

The aim of the present study, in view of the widespread geographical distribution of Lutzomyia (Nyssomyia) whitmani s.l. in Brazil, in close association with the regions of transmission of Leishmania (Viannia) braziliensis and L. (V.) shawi, is to investigate the distribution of this sand fly species and American cutaneous leishmaniasis (ACL) in relationship to vegetation and landscape ecology throughout Brazil. Thematic maps were elaborated by the MapInfo programme, giving information on the spatial distribution of L. whitmani s.l., in accordance with types of vegetation and foci of ACL. With regards to the known areas of transmission of ACL in Brazil, it is notable that L. (N.) whitmani s.l. occurs in most of them, where it has been implicated as a possible vector of L. (V.) braziliensis. The presence of L. whitmani s.l. has been registered in 26 states, the one exception being Santa Catarina; in some states such as Roraima, Acre, Tocantins, and Mato Grosso do Sul this sand fly species has been recorded in a large number of municipalities. L. whitmani s.l. has been found in association with a variety of vegetation types, including the Amazonian forest, savanna ("campos cerrados"), and northeastern savanna ("caatingas nordestinas" or "savana estépica").


Subject(s)
Humans , Animals , Geography , Insect Vectors/physiology , Leishmania braziliensis , Leishmaniasis, Cutaneous/epidemiology , Psychodidae/physiology , Brazil/epidemiology , Ecosystem , Insect Vectors/parasitology , Leishmaniasis, Cutaneous/transmission , Population Dynamics , Psychodidae/parasitology , Trees
18.
Cad. saúde pública ; 23(3): 725-730, mar. 2007. ilus
Article in English | LILACS | ID: lil-442000

ABSTRACT

The sand fly fauna in Itatiaia National Park, Rio de Janeiro, Brazil, was investigated in different habitats ranging from sylvatic areas to those altered by human activity related to ecotourism, specifically identifying species that have been suggested as potential leishmaniasis vectors. Sand flies were captured from June 2002 to March 2004, using CDC light traps and Shannon traps. A total of 1,256 sand fly specimens were captured, from species belonging to genera Lutzomyia and Brumptomyia: Brumptomyia guimaraesi, B. troglodytes, Lutzomyia (Lutzomyia) amarali, L. lanei, L. migonei, L. sallesi, L. edwardsi, L. tupynambai, L. (Pintomyia) pessoai, L. (P.) bianchigalatie, L. rupicola, L. (Psathyromyia) shannoni, L. pascalei, L. (Psychodopygus) matosi, L. (P.) davisi, L. (P.) hirsuta hirsuta, L. (P.) ayrozai, L. peresi, L. monticola, and L. misionensis. Worthy of special attention were four species that are considered potential vectors for cutaneous leishmaniasis in Brazil: L. ayrozai, L. hirsuta hirsuta, L. migonei, and L. davisi, representing 19.19 percent of the specimens captured in this study.


A fauna flebotomínica do Parque Nacional de Itatiaia, Rio de Janeiro, Brasil, foi investigada, em diferentes ambientes, envolvendo áreas silvestres e os ambientes ecologicamente alterados, principalmente por atividades ligadas ao ecoturismo, identificando espécies potencialmente vetoras de leishmanioses. As coletas de flebotomíneos foram realizadas no referido parque, no período de junho de 2002 a março de 2004, com armadilhas luminosas do tipo CDC e armadilha de Shannon. Foram coletados 1.256 flebotomíneos, correspondendo às seguintes espécies: Brumptomyia guimaraesi, B. troglodytes, Lutzomyia (Lutzomyia) amarali, L. lanei, L. migonei, L. sallesi, L. edwardsi, L. tupynambai, L. (Pintomyia) pessoai, L. (P.) bianchigalatie, L. rupicola, L. (Psathyromyia) shannoni, L. pascalei, L. (Psychodopygus) matosi, L. (P.) davisi, L. (P.) hirsuta hirsuta, L. (P.) ayrozai, L. peresi, L. monticola e L. misionensis. Merecem especial atenção por sua importância epidemiológica L.ayrozai, L. hirsuta hirsuta, L. migonei e L. davisi, representando 19,19 por cento dos exemplares capturados.


Subject(s)
Humans , Animals , Male , Female , Disease Vectors , Leishmaniasis , Pest Control, Biological , Psychodidae , Brazil , Fauna , Insect Vectors
19.
Mem. Inst. Oswaldo Cruz ; 101(8): 851-856, Dec. 2006. tab, graf
Article in English | LILACS | ID: lil-440571

ABSTRACT

Lutzomyia longipalpis females received single and mixed infections with Endotrypanum and Leishmania. Two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. The principal comparisons were performed between (1) two strains of Endotrypanum, (2) cloned versus primary sample of one strain of Endotrypanum, (3) Endotrypanum versus Leishmania guyanensis, and (4) the pattern of flagellates behaviour by optical microscopy in females with single or mixed infection versus the identification of parasites isolated from digestive tracts by isoenzyme electrophoresis. Flagellates of Endotrypanum showed distinct patterns of infection suggesting that there is variation between and within strains. The distribution of Endotrypanum and L. guyanensis differed significantly in relation to the colonization of the stomodeal valve. In co-infection with L. guyanensis, a large number of flagellates were seen to be plentifully infecting the stomodeal valve in significantly more specimens than in females infected by Endotrypanum only. However, the electrophoretic profiles of isoenzymes of parasites recovered from all co-infected specimens corresponded to Endotrypanum. This suggests that the mere correlation sand fly infection-biochemical analysis of isolates may induce parasitological incorrect consideration.


Subject(s)
Animals , Female , Isoenzymes/analysis , Leishmania guyanensis/pathogenicity , Psychodidae/parasitology , Trypanosomatina/pathogenicity , Digestive System/parasitology , Electrophoresis, Agar Gel , Flow Cytometry , Host-Parasite Interactions , Leishmania guyanensis/enzymology , Leishmania guyanensis/isolation & purification , Trypanosomatina/enzymology , Trypanosomatina/isolation & purification
20.
J Med Entomol ; 43(2): 262-6, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16619609

ABSTRACT

The effects of azadirachtin A added to the standard diet on the development, mortality, and metamorphosis of Lutzomyia longipalpis Lutz & Neiva, 1912 were studied. Concentrations of 0.1, 1.0, and 10.0 microg of azadirachtin/mg of diet significantly increased larval mortality in comparison with nontreated insects. Concentrations 0.1 and 1.0 microg blocked the molt of larvae, which remained as third instars until the end of the experiment. The 10 microg/mg concentration resulted in greater molt inhibition. In this group, all insects stopped their development as second instars. Simultaneous addition of ecdysone (1 microg/mg) to the standard diet containing azadirachtin counteracted the effects of azadirachtin on mortality and inhibition of ecdysis. These results indicate that azadirachtin is a potent growth inhibitor of L. longipalpis.


Subject(s)
Ecdysone/pharmacology , Insecticides , Limonins/pharmacology , Psychodidae/drug effects , Analysis of Variance , Animals , Larva/drug effects , Larva/growth & development , Metamorphosis, Biological/drug effects , Molting/drug effects , Mortality , Psychodidae/growth & development , Pupa/drug effects , Pupa/growth & development , Time Factors
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