ABSTRACT
Lutzomyia longipalpis s.l. is a complex of sibling species and is the principal vector of American visceral leishmaniasis. The present review summarises the diversity of efforts that have been undertaken to elucidate the number of unnamed species in this species complex and the phylogenetic relationships among them. A wide variety of evidence, including chemical, behavioral and molecular traits, suggests very recent speciation events and complex population structure in this group. Although significant advances have been achieved to date, differential vector capacity and the correlation between structure of parasite and vector populations have yet to be elucidated. Furthermore, increased knowledge about recent epidemiological changes, such as urbanisation, is essential for pursuing effective strategies for sandfly control in the New World.
Subject(s)
Animals , Psychodidae/classification , Psychodidae/genetics , Species Specificity , Genes, Insect , Biodiversity , Insect Vectors/classification , Insect Vectors/genetics , Leishmaniasis, Visceral/transmission , Phylogeny , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , BrazilABSTRACT
The phlebotomine sandflies of the province of Chaco, Argentina, are poorly known, with reports from more than 40 years or captures related with outbreaks of leishmaniasis. In here, Mycropygomyia peresi (Mangabeira) is reported for the first time in Argentina, extending the known dstribution of Migonemyia migonei (França), Evandromyia sallesi (Galvão & Coutinho), Mycropygomyia quinquefer (Dyar), Brumptomyia brumpti (Larousse) y Nemapalpus spp to the province of Chaco. Mg. migonei, together with Nyssomyia neivai (Pinto), Evandromyia cortelezzii (Brèthes), and Psathyromyia shannoni (Dyar) also captured in Chaco, were incriminated as vectors of Leishmania in Argentina.
Subject(s)
Animals , Psychodidae , Argentina , DemographyABSTRACT
There are nearly 500 species of sandflies in Americas, 30 of which are vectors of leishmaniasis. Evandromyia cortelezzii (Brèthes), E. sallesi (Galvão & Coutinho) and E. corumbaensis (Galati et al) comprise the cortelezzii complex. These species are morphologically similar and many times misidentified. Due to the epidemiological importance recently attributed to this complex, a detailed study was carried out in order to correct wrongful information due to their misidentification, and update their geographical distribution. Evandromyia corumbaensis was found to have a regional distribution, while the other two species are widely distributed in the Brazilian territory.
Existem aproximadamente 500 espécies de flebotomíneos nas Américas, sendo 30 delas vetores de leishmanioses. Evandromyia cortelezzii (Brèthes), E. sallesi (Galvão & Coutinho) e E. corumbaensis (Galati et al) formam o complexo cortelezzii. Essas espécies são semelhantes morfologicamente e muitas vezes confundidas, gerando erros em sua identificação específica. Devido à importância epidemiológica recentemente atribuída a esse complexo, foi realizado estudo detalhado a fim de corrigir as impropriedades cometidas durante a identificação específica das mesmas e atualizar sua distribuição geográfica. Evandromyia corumbaensis tem distribuição regional, enquanto as demais estão amplamente distribuídas pelo território brasileiro.
Subject(s)
Animals , Psychodidae , Brazil , DemographyABSTRACT
A group of 18 research workers involved in different aspects of the biology of Lutzomyia longipalpis discussed whether or not it is important to give taxonomically valid names to populations that have been defined by biological, biochemical and molecular methods to be reproductively isolated. The type material of this medically important species has been lost and because of this it was recommended that a colony should be established from insects captured in the region of the type area and that their description should serve as the basis for future descriptions. It was pointed out that there is a lack of uniformity in the naming of closely related American sand flies and that some of the differences between populations of Lu. longipalpis are greater than those between accepted species. The majority of the participants agreed that the populations that have been defined in the literature as sibling species should be named.
Subject(s)
Animals , Insect Vectors/classification , Psychodidae/classification , ClassificationABSTRACT
The phlebotomine sandflies of the state of Alagoas are poorly known, with more than 40 years since the last report on sandflies in the state. In here, Psathyromyia brasiliensis (Costa Lima), Micropygomyia quinquefer (Dyar,) and Evandromyia termitophila (Martins, Falcão & Silva) are registered for the first time in Alagoas. This report increases to nine the number of species collected in the state, including Lutzomyia longipalpis (Lutz & Neiva), Migonemyia migonei (França), Nyssomyia whitmani (Antunes & Coutinho) and Nyssomyia intermedia (Lutz & Neiva), all vectors of Leishmania in Brazil.
A fauna flebotomínica do Alagoas é uma das menos conhecida, sem registro de informações há mais de 40 anos. O presente trabalho registra Psathyromyia brasiliensis (Costa Lima), Micropygomyia quinquefer (Dyar) e Evandromyia termitophila (Martins, Falcão & Silva) pela primeira vez em Alagoas. Aumenta, assim, para nove o número de espécies conhecidas no estado, incluindo-se Lutzomyia longipalpis (Lutz & Neiva), Migonemyia migonei (França), Nyssomyia whitmani (Antunes & Coutinho) e Nyssomyia intermedia (Lutz & Neiva), importantes vetores de Leishmania no Brasil.
Subject(s)
Animals , Psychodidae , Brazil , Psychodidae/classificationABSTRACT
Leishmania (Viannia) lainsoni is the Leishmania species that presents the most distinct biological (morphology, growth in axenic culture medium), biochemical (enzymatic electrophoresis profile), and molecular biology characteristics, when compared to other species of the Viannia subgenus. Development of promastigote forms of this parasite attached to the wall of the pyloric and hind gut regions of sand fly vectors is a solid characteristic that allows its positioning in the Viannia subgenus. However, taxonomic data from biochemical and molecular techniques on this Leishmania species are still not conclusive. It is evident the difficulty in taxonomically positioning this borderline Leishmania species. In this review we present the data accumulated since L. (Viannia) lainsoni has been described and we discuss its position in the Viannia subgenus.
Subject(s)
Humans , Animals , DNA, Kinetoplast/analysis , Leishmania/classification , Disease Reservoirs , Host-Parasite Interactions , Insect Vectors , Leishmania/physiologyABSTRACT
Lutzomyia (Lutzomyia) cruzi has been named as a probable vector of Leishmania chagasi in Corumbá, Mato Grosso do Sul, Brazil. Taxonomically L. cruzi is closely related to the L. longipalpis species complex. Females of L. cruzi and L. longipalpis are morphologically indistinguishable and associated males must be examined carefully to confirm identifications. Chemical analysis hexane extracts of male L. cruzi has revealed the presence of a 9-methylgermacrene-B (C16), a homosesquiterpene (mw 218) previously shown to be the sex pheromone of one of the members of the L. longipalpis species complex
Subject(s)
Animals , Male , Female , Psychodidae , Sesquiterpenes , Sex Attractants , Brazil , ChickensABSTRACT
In the last few years the number of human cases of American visceral leishmaniasis in the Metropolitan Region of Belo Horizonte (MRBH), Minas Gerais, Brazil has increased, indicating an elevation in the transmission rate of the disease. The total number of notified human cases in the MRBH since 1994, when the first case was identified, up to 1999 was 345 of which 223 (65 percent) were from the city itself, indicating an urbanization of the disease in this region of Minas Gerais. The age distribution of visceral leishmaniasis cases in the MRBH shows a higher prevalence in children from 0-4 years old, responsible for 28.9 percent of the notifications. Clinical and immunological findings from dogs infected with Leishmania chagasi are described. The majority of these animals showed no sign of the disease. Sera from all infected dogs showed detectable Leishmania-induced high titles of antibodies based on the results of an indirect fluorescent antibody test. Samples of isolated Leishmania from human and dogs were characterized as L. (L.) chagasi by biochemical and molecular techniques
Subject(s)
Humans , Animals , Dogs , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Leishmania infantum/isolation & purification , Leishmaniasis, Visceral/epidemiology , Brazil/epidemiology , Endemic Diseases , Fluorescent Antibody Technique, Indirect , Incidence , Leishmania infantum/immunology , Leishmaniasis, Visceral/veterinary , Prevalence , Urban PopulationABSTRACT
Relata-se a ocorrência, pela primeira vez, do vetor da leishmanioses visceral, Lutzomyia longipalpis, na área urbana de Campo Grande, Mato Grosso do Sul. Discute-se a importância deste encontro na transmissäo da doença nessa área
Subject(s)
Psychodidae , Leishmaniasis, Visceral/transmission , Brazil , Disease VectorsABSTRACT
The influence of altitude and latitude on some structure sizes of Lutzomyia intermedia was noted; several structures of insects collected in higher localities were greater, according to Bergmann's rule. This influence was more remarkable in two localities of the State of Espírito Santo, probably due to greater differences in altitude. Comparing insects from different latitudes, more differences were noted in comparisons of insects from low altitude localities than in those of material from higher altitudes. The small number of differences between insects collected in July and in December does not indicate a defined influence of season and temperature on the size of adults. The possible epidemiological implications of these variations are discussed.
Subject(s)
Animals , Male , Female , Altitude , Psychodidae/anatomy & histology , SeasonsABSTRACT
The present paper reports the experimental treatment of hamsters infected with Leishmania chagasi and Leishmania amazonensis with sodium stibogluconate (20mg/kg/day x 20 days). Only with L. chagasi did the treatment result in the complete elimination of parasites from the spleen. However, no parasitological cure was achieved in hamsters infected with L. amazonensis
Subject(s)
Animals , Cricetinae , Antimony Sodium Gluconate/therapeutic use , Leishmania , Leishmania mexicana , Leishmaniasis/drug therapy , Leishmaniasis, Cutaneous/drug therapyABSTRACT
A new species of sand fly from Santa Cruz, state of Rio de Janeiro, Brazil is described as Lutzomyia (Pressatia) mamedei.