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1.
Mem. Inst. Oswaldo Cruz ; 116: e200571, 2021. tab, graf
Article in English | LILACS | ID: biblio-1154878

ABSTRACT

Leishmania infantum chagasi is the causative agent and Lutzomyia longipalpis is the main vector of visceral leishmaniasis in the Americas. We investigated the expression of Leishmania genes within L. longipalpis after artificial infection. mRNAs from genes involved in sugar and amino acid metabolism were upregulated at times of high parasite proliferation inside the insect. mRNAs from genes involved in metacyclogenesis had higher expression in late stages of infection. Other modulated genes of interest were involved in immunomodulation, purine salvage pathway and protein recycling. These data reveal aspects of the adaptation of the parasite to the microenvironment of the vector gut and reflect the preparation for infection in the vertebrate.


Subject(s)
Animals , Psychodidae/parasitology , Leishmania infantum/genetics , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmaniasis, Visceral/transmission , Psychodidae/genetics , Brazil , Gene Expression , Reverse Transcriptase Polymerase Chain Reaction/methods , Leishmaniasis, Visceral/parasitology , Leishmaniasis, Visceral/epidemiology , Life Cycle Stages
2.
Hist. ciênc. saúde-Manguinhos ; 27(3): 741-761, set. 2020. tab, graf
Article in Portuguese | LILACS | ID: biblio-1134073

ABSTRACT

Resumo O artigo faz análise histórica da emergência da leishmaniose tegumentar americana como objeto do conhecimento e desafio médico-sanitário no Amazonas desde a década de 1970. Fornece visão geral dessa época, as medidas sanitárias e os estudos científicos realizados no contexto de implantação dos principais projetos de desenvolvimento regionais executados em nome da política de integração nacional do governo federal. Utiliza como metodologia a análise documental de leis, produção científica, relatórios de pesquisa, boletins epidemiológicos e jornais. Os resultados da pesquisa mostram que a doença surgiu no Amazonas associando o grande problema de saúde com mudanças político-econômicas e alterações socioambientais.


Abstract The history of the emergence of American cutaneous leishmaniasis in the Brazilian state of Amazonas since the 1970s is analyzed as an object of knowledge and a medical and public health challenge. An overview of the period is provided, including the public health measures and scientific studies undertaken in the context of the execution of large-scale regional developments pursued in the name of national integration by the federal government. The methodology uses documental analysis of laws, the scientific literature, research reports, epidemiological bulletins, and newspapers. The results show that American cutaneous leishmaniasis emerged as a major health problem in Amazonas in close association with the political, economic, and socioenvironmental changes seen in the period.


Subject(s)
Humans , Animals , Public Health/history , Leishmaniasis, Cutaneous/history , Conservation of Natural Resources , Leishmania/isolation & purification , Psychodidae/parasitology , Urbanization/history , Leishmania braziliensis/isolation & purification , Brazil/epidemiology , Insect Control/history , Leishmaniasis, Cutaneous/transmission , Leishmaniasis, Cutaneous/epidemiology , Leishmania guyanensis/isolation & purification , Industrial Development/history , Insect Vectors
3.
Rev. peru. med. exp. salud publica ; 37(1): 87-92, ene.-mar. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1101806

ABSTRACT

RESUMEN En el Perú, la leishmaniasis es una enfermedad metaxénica que representa un serio problema de salud pública, debido a su amplia distribución y al número de personas en riesgo de contraer la enfermedad, siendo la población vulnerable principalmente las personas de bajos recursos económicos. El estudio se realizó a partir de pacientes que fueron derivados al Instituto Nacional de Salud entre el 2006 y el 2011 para que se les realizara el diagnóstico especializado. La identificación de la especie de Leishmania infectante se desarrolló mediante el análisis de las curvas de disociación (HRMA) obtenidas a partir del ADN genómico de promastigotes y amastigotes, lo que permitió identificar las especies de Leishmania (Viannia) braziliensis, Leishmania (V.) guyanensis, Leishmania (V.) peruviana como las más prevalentes, además de Leishmania (V.) lainsoni y Leishmania (L.) amazonensis.


ABSTRACT In Peru, leishmaniasis is a metaxenic disease that represents a serious public health problem, due to its wide distribution and the number of people in danger of contracting the disease, being the vulnerable population mainly those with low economic resources. The study was conducted from patients who were derived to Peru's National Institute of Health between 2006 and 2011 so that the specialized diagnosis could be carried out. The identification of the species of infectious Leishmania was developed through the analysis of the High-Resolution Melting Analysis obtained from the genomic DNA of promastigotes and amastigotes, which allows to identify the species of Leishmania (Viannia) braziliensis, Leishmania (V.) guyanensis, Leishmania (V.) peruviana as more prevalent, in addition to Leishmania (V.) lainsoni and Leishmania (L.) amazonensis.


Subject(s)
Humans , Leishmaniasis , Leishmania , Peru/epidemiology , Leishmania braziliensis/isolation & purification , Leishmania braziliensis/genetics , Leishmaniasis/parasitology , Leishmaniasis/therapy , Leishmaniasis/epidemiology , Leishmania guyanensis/isolation & purification , Leishmania guyanensis/genetics , Leishmania/isolation & purification , Leishmania/genetics
4.
Mem. Inst. Oswaldo Cruz ; 115: e200157, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135268

ABSTRACT

BACKGROUND In Acre state, Brazil, the dissemination of cutaneous leishmaniasis has increased in recent years, with limited knowledge of the potential Leishmania spp. vectors involved. OBJECTIVES Here, data concerning the sandfly fauna of Brasiléia municipality, Leishmania DNA-detection rates and the identification of blood meal sources of insects captured in 2013-2015 are presented. METHODS Parasite detection in female sandflies was performed individually by multiplex polymerase chain reaction (PCR) (Leishmania kDNA/sandfly cacophony-gene), with the identification of Leishmania spp. by hsp70-PCR and sequencing. The identification of blood gut-content from fed females was performed by cyt b-PCR and sequencing. FINDINGS A total of 4,473 sandflies were captured. A subgroup of 864 non-blood-fed females evaluated for the presence of Leishmania DNA showed 2.9% positivity for Leishmania (Viannia) braziliensis and L. (V.) guyanensis. The identification of blood meal sources was performed in 96 blood-fed females, allowing the identification of 13 vertebrate species. In nine/96 fed females, DNA from L. (V.) shawi, L. (V.) guyanensis, L. (V.) braziliensis and Endotrypanum sp. was detected. MAIN CONCLUSIONS In Brumptomyia sp. and Evandromyia termitophila, the first report of Leishmania DNA-detection is provided in Acre; Nyssomyia shawi is implicated as potential vector of L. (V.) braziliensis and L. (V.) guyanensis for the first time in Brazil.


Subject(s)
Animals , Female , Psychodidae/parasitology , DNA/analysis , Insect Vectors/genetics , Leishmania/genetics , Psychodidae/classification , Brazil , Polymerase Chain Reaction , DNA, Protozoan/analysis , Leishmaniasis, Cutaneous/transmission , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification
5.
Rev. Soc. Bras. Med. Trop ; 53: e20190320, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057289

ABSTRACT

Abstract INTRODUCTION: This study aimed to investigate human exposure to Leishmania spp. infection and sandflies in an area endemic for the disease. METHODS: The presence of antibodies specific for Leishmania spp. and saliva of Lutzomyia spp. and that of L. infantum DNA in blood were evaluated. RESULTS: Antibodies against Leishmania spp. and sandfly saliva were observed in 20.8% and 37.7% of individuals, respectively. DNA of Leishmania spp. was amplified from the blood of one patient. CONCLUSIONS: The results suggest that Leishmania spp. infection may be underdiagnosed in this area.


Subject(s)
Humans , Animals , Male , Female , Adolescent , Adult , Aged , Young Adult , Psychodidae/parasitology , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmaniasis, Visceral/transmission , Brazil , Enzyme-Linked Immunosorbent Assay , Polymerase Chain Reaction , Leishmania/genetics , Leishmania/immunology , Leishmaniasis, Visceral/epidemiology , Middle Aged
6.
Int. j. odontostomatol. (Print) ; 14(3): 342-347, 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1114904

ABSTRACT

La Leishmaniasis es un grupo de enfermedades transmitidas por vectores y causada por la Leishmania, un parásito intracelular, que se presenta de preferencia en regiones tropicales y subtropicales. Se manifiesta mediante un amplio rango de formas clínicas como la cutánea, mucocutánea, y visceral, dependiendo de la especie y respuesta inmunológica del paciente. Se presenta el caso de un hombre de 35 años que acudió derivado a Unidad de Estomatología del Hospital Señor del Milagro, Salta, Argentina, presentando en la cavidad oral lesión, granulomatosa, ulcerada, dolorosa a la palpación, única, en paladar blando, de tres meses de evolución. Se realizaron estudios serológicos, parasitológicos y PCR. Los ELISAs lisados, PCRs y cultivos de materiales de lesiones fueron positivos, confirmando diagnóstico de leishmaniasis mucocutánea. El paciente fue derivado al Servicio de Dermatología donde recibió tratamiento con Antimoniato de Meglumina, con repuesta clínica favorable. El conocimiento de las manifestaciones orales puede llevar al diagnóstico clínico de leishmaniasis mucocutánea por parte del odontólogo, pudiendo entregar un tratamiento oportuno y a la vez ayudar al paciente, evitando complicaciones de esta enfermedad.


Leishmaniasis is a group of vector-borne diseases caused by Leishmania, an intracellular parasite, which occurs preferentially in tropical and subtropical regions. It manifests itself through a wide range of clinical forms such as cutaneous, mucocutaneous, and visceral, depending on the species and the patient's immune response. We present a case of a 35-year-old man who was referred to the Stomatology Unit of the Señor del Milagro Hospital, Salta, Argentina, presenting in the oral cavity lesion, granulomatous, ulcerated, painful on palpation, unique, soft palate with three months of evolution. Serological, parasitological and PCR studies were performed. Lysed ELISAs, PCRs and cultures of lesion materials were positive, confirming diagnosis of mucocutaneous leishmaniasis. The patient was referred to the Dermatology Service where he received treatment with Meglumine Antimony, with favorable clinical response. The knowledge of the oral manifestations can lead to the clinical diagnosis of mucocutaneous leishmaniasis by the dentist, being able to provide timely treatment and at the same time help the patient, avoiding complications of this disease.


Subject(s)
Humans , Male , Adult , Leishmaniasis, Mucocutaneous/diagnosis , Leishmaniasis, Mucocutaneous/parasitology , Mouth Diseases/diagnosis , Mouth Diseases/parasitology , Paracoccidioidomycosis/diagnosis , Enzyme-Linked Immunosorbent Assay , Polymerase Chain Reaction , Diagnosis, Differential , Histoplasmosis/diagnosis , Leishmania/isolation & purification , Mouth Mucosa/parasitology
7.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 2103-2106, Nov.-Dec. 2019. tab
Article in English | LILACS, VETINDEX | ID: biblio-1055126

ABSTRACT

Devido à ampla distribuição da leishmaniose visceral (LV) no Brasil e à importância dos cães no ciclo de transmissão dessa zoonose, o presente estudo teve como objetivo avaliar a ocorrência de Leishmania spp. e caracterizar a espécie circulante em diferentes tecidos biológicos de cães da Baixada Cuiabana, Mato Grosso, Brasil. Amostras de sangue, linfonodo e medula óssea foram coletadas de 205 cães para realização de análise parasitológica por citologia e análise molecular por meio da nested PCR (nPCR) e do sequenciamento . Dos 205 cães estudados, 34 (16,58%) animais foram positivos pela nPCR, dos quais 12 possuíam formas amastigotas de Leishmania spp. na citologia. Amostras positivas na nPCR foram sequenciadas e caracterizadas como Leishmania (Leishmania) infantum. A sensibilidade da nPCR nas amostras de medula óssea, linfonodo e sangue foi de 94,87%, 91,8% e 98%, respectivamente, enquanto a especificidade foi de 100% para todas as amostras. O presente estudo relata a ocorrência de LV canina em 16,58% dos cães analisados, caracterizando a L. infantum como agente causador. Entre as amostras avaliadas, a medula óssea foi a única a apresentar concordância substancial entre as técnicas de nPCR e citologia (k = 0,643), sendo considerada a amostra mais adequada para o diagnóstico da doença. Os resultados ampliam o conhecimento de espécies de Leishmania infectando cães no Brasil, destacando a importância da identificação etiológica em áreas com escassos dados moleculares.(AU)


Subject(s)
Animals , Dogs , Leishmania infantum/isolation & purification , Leishmania/isolation & purification , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/veterinary , Polymerase Chain Reaction/veterinary
8.
Rev. bras. parasitol. vet ; 28(4): 574-581, Oct.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1057998

ABSTRACT

Abstract Leishmaniases are a group of diseases of zoonotic importance caused by over 20 species of protozoa of the genus Leishmania, in which domestic dogs are considered to be the main reservoir for the disease. However, the involvement of other vertebrates as reservoirs for these parasites has also been investigated. Therefore, the objective of the present study was to carry out a systematic review with meta-analysis on occurrences of leishmaniasis in equids. The case reports described animals with cutaneous symptoms of leishmaniasis (papules, nodules, ulcers or crusts) that regressed spontaneously, located mainly on the head and limbs, from which three species of protozoa were identified in the lesions: Leishmania braziliensis, Leishmania infantum and Leishmania siamensis. In turn, the meta-analysis showed a combined prevalence of 25%, although with high heterogeneity among the studies, which was attributed to the use of different methods for diagnosing the disease. Leishmaniasis in equids is a benign disease but it should be included in the differential diagnosis of cutaneous diseases among these species. Seroepidemiological studies are important in investigating and monitoring suspected exposure of these hosts to the parasite, especially in endemic areas. However, there is also a need to standardize diagnostic methods.


Resumo As leishmanioses são um grupo de doenças de importância zoonótica causadas por mais de 20 espécies de protozoários do gênero Leishmania, sendo o cão doméstico considerado o principal reservatório da doença. No entanto, diversas pesquisas têm investigado o envolvimento de outros vertebrados como reservatórios do parasita. Portanto, o objetivo do presente estudo foi realizar uma revisão sistemática com meta-análise da ocorrência de leishmaniose em equídeos. Os relatos de caso descreviam animais com sintomas cutâneos de leishmaniose (pápulas, nódulos, úlceras, crostas) que regrediam espontaneamente, localizadas principalmente na cabeça e membros, sendo identificadas três espécies do protozoário nas lesões: Leishmania braziliensis, Leishmania infantum e Leishmania siamensis. Por sua vez, a meta-análise evidenciou uma prevalência combinada de 25%, porém com alta heterogeneidade entre os estudos, atribuída às diferenças nos métodos utilizados no diagnóstico da doença. A leishmaniose em equídeos é uma doença benigna, porém deve ser incluída no diagnóstico diferencial de doenças cutâneas nessas espécies. Os estudos soroepidemiológicos são importantes para investigar e monitorar a suspeita de exposição desses hospedeiros ao parasita, principalmente em áreas endêmicas, porém há necessidade de padronização dos métodos de diagnóstico.


Subject(s)
Animals , Leishmaniasis/veterinary , Horse Diseases/parasitology , Horses/parasitology , Leishmania/isolation & purification , Disease Reservoirs , Leishmania/classification
9.
Biomédica (Bogotá) ; 39(2): 252-264, ene.-jun. 2019. tab, graf
Article in English | LILACS | ID: biblio-1011438

ABSTRACT

Abstract Introduction: The study of the interaction between the parasite, the vector and the mammalian hosts, including man, allows to understand the behavior of the leishmaniases. Objective: To determine the presence of Lutzomyia species and to detect the Leishmania infection in Didelphis marsupialis in an endemic area for visceral leishmaniasis. Materials and methods: Phlebotomine fauna and individuals of D. marsupialis were collected with CDC and Tomahawk™ traps, respectively. The species of Lutzomyia were identified using the Young and Duncan key (1994). Ear and tail biopsies and blood samples from D. marsupialis were taken to identify the Leishmania species by amplifying a fragment of the gene associated with the 70 kD heat shock protein. Results: Seven Lutzomyia species were identified: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana and Lu. trinidadensis. The first three species have epidemiological importance in Colombia because of their implications in the transmission of the Leishmania parasite. Sixty-five tissue samples from 19 D. marsupialis individuals were negative for Leishmania spp. Conclusions: The presence of the Lutzomyia species that have been identified as vectors for Leishmania inside and around houses in the village of El Bledo, in El Carmen de Bolívar represents a risk of infection. Furthermore, the presence of Lu. panamensis is reported for first time in El Carmen de Bolívar in Colombia. Although the lack of detection of Leishmania spp. in D. marsupialis samples may suggest that D. marsupialis does not play an important role in the transmission cycle of Leishmania in this region, it is necessary to carry out further longitudinal studies to confirm this hypothesis.


Resumen Introducción. El estudio de la interacción entre el parásito, el vector y los huéspedes mamíferos, incluido el hombre, permite entender el comportamiento de la leishmaniasis. Objetivo. Determinar la presencia de especies del género Lutzomyia y detectar la infección por Leishmania spp. en Didelphis marsupialis en un área endémica de leishmaniasis visceral. Materiales y métodos. Se recolectaron flebotomíneos y D. marsupialis con trampas CDC y Tomahawk™, respectivamente. Las especies de Lutzomyia se identificaron usando la clave de Young y Duncan, 1994. Se tomaron biopsias de oreja, cola y muestras de sangre de D. marsupialis para diagnosticar Leishmania spp. mediante la amplificación de un fragmento del gen de la proteína de choque térmico de 70 kD. Resultados. Se identificaron siete especies de Lutzomyia: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana y Lu. trinidadensis. Las tres primeras especies son reconocidas como vectores en el país por estar implicadas en la transmisión de Leishmania spp. En total, 65 muestras de tejidos de oreja, cola y de sangre provenientes de 19 D. marsupialis fueron negativas para Leishmania spp. en la PCR-HSP70. Conclusiones. La presencia de flebotomíneos con importancia epidemiológica en la zona evaluada representa un riesgo de transmisión. Asimismo, Lu. panamensis es reportada por primera vez en El Bledo (Carmen de Bolívar). La ausencia de Leishmania spp. en D. marsupialis podría sugerir que esta especie no tiene un papel importante en el ciclo de transmisión de Leishmania en la vereda El Bledo, por lo que es necesario profundizar en estudios longitudinales para corroborar esta hipótesis.


Subject(s)
Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Young Adult , Psychodidae , Disease Reservoirs/parasitology , Didelphis , Insect Vectors , Leishmaniasis, Visceral/epidemiology , Psychodidae/parasitology , Rural Population , Species Specificity , Tail/parasitology , Blood/parasitology , Colombia/epidemiology , HSP70 Heat-Shock Proteins/genetics , Endemic Diseases , Didelphis/parasitology , Ear, External/parasitology , Housing , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Leishmaniasis, Visceral/transmission
10.
Braz. j. infect. dis ; 23(2): 111-120, Mar.-Apr. 2019. tab
Article in English | LILACS | ID: biblio-1011573

ABSTRACT

ABSTRACT Visceral leishmaniasis is a serious and debilitating infection with high fatality rate in tropical and subtropical countries. As clinical symptoms of visceral leishmaniasis are not so specific, confirmatory diagnostic methods with high sensitivity and specificity are needed. Noninvasive methods have been developed using urine as a clinical sample for visceral leishmaniasis diagnosis. In fact, there is a clear correlation between kidney impairment and Leishmania DNA in urine. However, it has been proved that Leishmania nucleic acid may also be isolated from patients without any sign of renal involvement. Even though urine has become a promissing biological sample, it is still not widely used due to several issues, such as (i) incomprehension of the whole renal pathophysiology process in visceral leishmaniasis, (ii) presence of many amplification inhibitors in urine, and (iii) lack of an efficient urinary DNA extraction method. In this article, we performed a literature review to bring a new perspective for Leishmania DNA isolation in urine.


Subject(s)
Humans , DNA, Protozoan/urine , Leishmania/genetics , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/urine , Polymerase Chain Reaction/methods , Reproducibility of Results , DNA, Protozoan/isolation & purification , Sensitivity and Specificity , Leishmania/isolation & purification
12.
Braz. j. med. biol. res ; 52(9): e8224, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019569

ABSTRACT

Leishmaniasis is a neglected disease that affects a large part of the world population. Knowing the sand fly fauna of a region is of fundamental importance for guiding health surveillance actions related to the prevention and control of leishmaniasis. A total of 86 specimens of sand flies (60 females and 26 males) were collected. Using the classification proposed by Galati (2003), the following species were identified: Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1920), Evandromyia cortelezzi (Brethes, 1923), Ev. sallesi (Galvão & Coutinho, 1939), Nyssomyia whitmani (Atunes & Coutinho, 1939), Psathyromyia lutziana (Costa Lima, 1932), Ev. lenti (Mangabeira, 1938), Brumptomyia sp. (França and Parrot, 1921), and Pressatia sp. (Mangabeira, 1942). Using PCR with internal transcribed spacer target to identify infected sand flies, five Lu. longipalpis females were infected with Leishmania spp. Despite the small number of specimens collected, considerable species diversity was found in the study area.


Subject(s)
Animals , Male , Female , Psychodidae/classification , Psychodidae/parasitology , RNA, Protozoan/genetics , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Brazil , Leishmaniasis/transmission , Polymerase Chain Reaction , DNA, Ribosomal Spacer/genetics , Leishmania/genetics
13.
São Paulo; s.n; 2018. 85 p.
Thesis in Portuguese | LILACS | ID: biblio-970056

ABSTRACT

Introdução. Leishmanioses são zoonoses que têm como agentes etiológicos tripanossomatídeos de várias espécies do gênero Leishmania. Elas são transmitidas aos hospedeiros vertebrados por Phlebotominae (Diptera, Psychodidae). As infecções por Leishmania podem se manifestar nas formas visceral (LV) e tegumentar (LT); ambas são sérios problemas de saúde pública no Brasil, que se encontra entre os países do mundo com as mais altas incidências. Dentre as atividades de controle das leishmanioses, as da vigilância entomológica estão voltadas para a redução da taxa de contato dos vetores com os hospedeiros vertebrados e identificar áreas de risco de transmissão. Neste sentido, a detecção de fêmeas de flebotomíneos naturalmente infectadas por Leishmania constitui-se numa das estratégias. Essa detecção pode ser realizada apenas por meio de análises moleculares ou estas serem precedidas de dissecção das fêmeas para observação da presença de flagelados em seus tratos digestórios. A observação dessas formas no trato digestório pode indicar a capacidade do parasita em resistir aos processos de sua eliminação, dependendo do local onde se encontra, e a que subgênero (Leishmania ou Viannia) pertence. No Brasil, a LV tem sido associada a espécie Leishmania (Leishmania) infantum. A LT tem como agentes espécies de ambos os subgêneros. O presente projeto teve como objetivo desenvolver um manual no qual são descritos os processos para se realizar a investigação da infecção natural por flagelados em fêmeas de flebotomíneos. Materiais e Métodos. Para a elaboração do manual foram examinadas fêmeas selvagens e outras provenientes de colônias alimentadas em hamsters infectados experimentalmente por Leishmania braziliensis e, posteriormente, dissecadas e examinadas em microscópio. Os parasitas utilizados nos experimentos de infecção em laboratório são oriundos de cultivos mantidos em laboratório. As espécies examinadas foram Lutzomyia longipalpis, Nyssomyia neivai e Pintomyia fischeri. Foram descritos os cuidados necessários à preservação dos espécimes em campo e transporte ao laboratório, de modo a tornar viável a dissecção e exame dos espécimes. As capturas realizadas em campo para o estudo permitiram tanto a obtenção dos espécimes como a elaboração do item que trata dos cuidados com as amostras. A documentação das múltiplas etapas de dissecção e exame dos espécimes necessários para o estudo foram realizados por meio de câmera fotográfica acoplada a microscópio óptico. Resultados. São apresentados na forma de manual. Neste são descritos e ilustrados aspectos das técnicas de captura, cuidados com os insetos no campo e laboratório, transporte de amostras vivas, o processo de dissecção da fêmea e a observação de seu tubo digestório para a investigação da presença de flagelados, e de estruturas de sua genitália, para a identificação da espécie de flebotomíneo. Apresenta-se ainda um protocolo a ser utilizado na preservação dos espécimes que forem encontrados infectados para posterior análise molecular e identificação específica do parasita. Conclusões. Com os tópicos apresentados no manual, espera-se contribuir com o programa vigilância epidemiológica das leishmanioses, em atividades da vigilância entomológica voltadas para a identificação de áreas de risco de transmissão dessas doenças e obter evidências que apontem para o potencial de espécies que possam estar atuando como vetores permissíveis de Leishmania spp


Introduction. Leishmaniases are zoonoses having trypanosomatids of several species of the genus Leishmania as etiological agents, transmitted to vertebrate hosts by the bite of females of Phlebotominae (Diptera, Psychodidae). These parasitoses can manifest in visceral (VL) and tegumentary (TL) forms, both being serious public health problems in Brazil, which is among the countries of the world with the highest incidence rates. Among the activities of control of leishmaniases, those of entomological surveillance are aimed at reducing the contact rate of the vectors with the vertebrate hosts and also to identify areas in risk of the disease transmission. In this sense, the detection of sand fly females naturally infected with Leishmania is one of the strategies. This detection can be carried out exclusively by means of molecular analyzes or these being preceded by dissection of the females to observe the presence of flagellates in their guts. The observation of flagellate forms in the gut indicates the ability of the parasites to resist the processes of their elimination, and also to identify the subgenus (Leishmania or Viannia) to which the parasites belong. In Brazil, the VL infection is attributed to Leishmania (Leishmania) infantum, while in TL, there are various agents belonging to both subgenera. Objective. To develop a manual in which the processes for the investigation of the natural infection by flagellates in sand fly females are described and illustrated. Material and Method. For the construction of the manual, observation of infection by flagellates was made through the dissection of wild or laboratory females of Lutzomyia longipalpis, Nyssomyia neivai and Pintomyia fischeri, experimentally infected with Leishmania braziliensis. The description of care in the preservation of the specimens in the field and in their transport to the laboratory, in order to make feasible the dissection, was made based on the collection undertaken in this project. The documentation was made by means of a photographic camera coupled to an optical microscope. Result. A manual is presented describing and illustrating aspects of collection techniques, insect care in the field and laboratory, transport of the live samples, the dissection process and observation, respectively, of the female gut for the investigation of the flagellate presence and genitalia structure for the identification of the phlebotomine species. Protocol is also presented to be used in the preservation of the specimens found infected for subsequent molecular analysis and the specific identification of the parasite. Conclusions. With the topics presented in this manual, we intend to contribute to the program of epidemiological surveillance of leishmaniases, in activities of entomological surveillance, in the identification of areas of risk of transmission of these diseases, as well as to obtain evidence about the potential of species that may act as permissible vectors of Leishmania spp


Subject(s)
Animals , Psychodidae , Leishmaniasis , Dissection , Research , Manuals as Topic , Leishmania/isolation & purification
14.
Mem. Inst. Oswaldo Cruz ; 112(10): 681-691, Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-894835

ABSTRACT

BACKGROUND Knowledge on synanthropic phlebotomines and their natural infection by Leishmania is necessary for the identification of potential areas for leishmaniasis occurrence. OBJECTIVE To analyse the occurrence of Phlebotominae in gallery forests and household units (HUs) in the city of Palmas and to determine the rate of natural infection by trypanosomatids. METHODS Gallery forests and adjacent household areas were sampled on July (dry season) and November (rainy season) in 2014. The total sampling effort was 960 HP light traps and eight Shannon traps. Trypanosomatids were detected in Phlebotominae females through the amplification of the SSU rDNA region, and the positive samples were used in ITS1-PCR. Trypanosomatid species were identified using sequencing. FINDINGS A total of 1,527 sand flies representing 30 species were captured in which 949 (28 spp.) and 578 (22 spp.) were registered in July and November, respectively. In July, more specimens were captured in the gallery forests than in the HUs, and Nyssomyia whitmani was particularly frequent. In November, most of the specimens were found in the HUs, and again, Ny. whitmani was the predominant species. Lutzomyia longipalpis was commonly found in domestic areas, while Bichromomyia flaviscutellata was most frequent in gallery forests. Molecular analysis of 154 pools of females (752 specimens) identified Leishmania amazonensis, L. infantum, and Crithidia fasciculata in Ny. whitmani, as well as L. amazonensis in Lu. longipalpis, Trypanosoma sp. and L. amazonensis in Pintomyia christenseni, and L. amazonensis in both Psathyromyia hermanlenti and Evandromyia walkeri. MAIN CONCLUSIONS These results show the importance of gallery forests in maintaining Phlebotominae populations in the dry month, as well as their frequent occurrence in household units in the rainy month. This is the first study to identify Leishmania, Trypanosoma, and Crithidia species in Phlebotominae collected in Palmas, Tocantins, Brazil.


Subject(s)
Animals , Female , Psychodidae/classification , Psychodidae/parasitology , Leishmania/isolation & purification , Forests , Grassland , Insect Vectors
15.
Biomédica (Bogotá) ; 37(supl.2): 83-97, jul.-set. 2017. tab, graf
Article in Spanish | LILACS | ID: biblio-888528

ABSTRACT

Resumen Introducción. La provincia de Pichincha, Ecuador, es un área endémica de leishmaniasis cutánea, en donde se han determinado como vectores los flebotomíneos antropofílicos con infección natural por Leishmania spp. Sin embargo, no se ha evaluado el papel en la transmisión de las especies zoofílicas. Objetivo. Evaluar la infección natural por Leishmania en dos especies de flebotomíneos zoofílicos, Lutzomyia reburra y Lu. barrettoi majuscula, y en una antropofílica, Lu. trapidoi, así como la endofagia y la sinantropía de estas especies en el noroccidente de Pichincha. Materiales y métodos. Los flebotomíneos se recolectaron en trampas de luz CDC colocadas en diferentes hábitats y altitudes en sitios que son focos de leishmaniasis cutánea. La infección con Leishmania spp. se detectó en el ADN genómico de hembras de las especies de flebotomíneos de interés. Se amplificó el gen espaciador interno de la transcripción del ARN ribosómico, unidad I (ITS1), y los genes de las topoisomerasas mitocondrial II (mtTOPOII) y nuclear II (TopoII). Se determinaron los porcentajes de positividad para Leishmania a escala espaciotemporal, la proporción de endofagia y el índice de sinantropía. Resultados. Se determinó la presencia de infección natural por Le. amazonensis en Lu. reburra (9,5 %) y Lu. b. majuscula (23,8 %); en Lu. trapidoi se detectaron Le. amazonensis, Le. brazilienis y Le. naiffilainsoni. Los flebotomíneos eran asinantrópicos y con baja endofagia. Conclusión. Se registró por primera vez la presencia de infección natural en Lu. reburra y Lu. barrettoi majuscula por Le. amazonensis, y se demostró la importancia de los flebotomíneos zoofílicos en el mantenimiento del ciclo de transmisión de Leishmania spp. en focos endémicos.


Abstract Introduction: The province of Pichincha in Ecuador is an endemic area of cutaneous leishmaniasis, where anthropophilic sand flies with natural infection by Leishmania, have been reported as vectors. However, the role in transmission of zoophilic species has not been evaluated. Objective: To evaluate natural infection by Leishmania in two zoophilic phlebotomine sand fly species, Lutzomyia reburra and Lu. barrettoi majuscula, and one anthropophilic species, Lu. trapidoi, as well as the endophagy and synanthropism of these species in the northwest of Pichincha. Materials and methods: Phlebotomines were collected using CDC light traps in different habitats and altitudes with presence of cutaneous leishmaniasis. Leishmania infection was detected using genomic DNA from females of the collected sand flies. We amplified the internal transcribed spacer gene of ribosomal RNA I (ITS1), the mitochondrial topoisomerase II gene (mtTOPOII), and the nuclear topoisomerase II gene (TopoII). Percentages of positivity for Leishmania, at spatio-temporal scale, proportion of endophagy and synanthropism index were calculated. Results: Natural infection was determined for Le. amazonensis in Lu. reburra (9.5%) and Lu. b. majuscula (23.8%), while in Lu. trapidoi we detected Le. amazonensis, Le. brazilienis and Le. naiffilainsoni. Phlebotomines were asynanthropic and with low endophagy. Conclusion: Natural infection with Le. amazonensis was recorded for the first time in Lu. reburra and Lu. b. majuscula, demonstrating the importance of zoophilic phlebotomines in the maintenance of the Leishmania transmission cycle in endemic foci.


Subject(s)
Animals , Female , Psychodidae/parasitology , Leishmaniasis, Cutaneous/transmission , Insect Vectors/parasitology , Leishmania/isolation & purification , Phylogeny , Species Specificity , Protozoan Proteins/genetics , Cell Nucleus/enzymology , DNA, Protozoan/analysis , Leishmaniasis, Cutaneous/parasitology , DNA Topoisomerases, Type II/genetics , DNA, Ribosomal Spacer/analysis , Ecuador , Feeding Behavior , Phylogeography , Leishmania/physiology , Leishmania/genetics , Mitochondria/enzymology
16.
Mem. Inst. Oswaldo Cruz ; 112(7): 517-519, July 2017.
Article in English | LILACS | ID: biblio-841810

ABSTRACT

The sandfly Trichophoromyia auraensis has recently evolved as a proven vector of Leishmania (Viannia) endemic to state of Acre in the north of Brazil. This note is intended to propose a correction in the report of the first occurrence of natural infection of Leishmania (Viannia) in this species. We and the other scientific groups reinforced that Tr. auraensis is a possible vector involved in the transmission of American cutaneous leishmaniasis in Acre, Brazil.


Subject(s)
Animals , Leishmaniasis, Cutaneous/parasitology , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Psychodidae , Psychodidae/parasitology , Brazil
17.
Mem. Inst. Oswaldo Cruz ; 112(4): 309-318, Apr. 2017. tab, graf
Article in English | LILACS | ID: biblio-841787

ABSTRACT

BACKGROUND Leishmaniases are a serious health problem in southeast Brazil, including the city of Belo Horizonte (BH), Minas Gerais state (MG), where there are high rates of incidence and mortality due to visceral leishmaniases. BH is divided into nine sanitary districts (SD) of which one, the Venda Nova SD, was selected for this study because it has high rates of positivity for canine leishmaniasis and high incidence of human leishmaniasis. OBJECTIVES This study aimed to survey the sand fly fauna in Venda Nova SD from August 2011 to July 2013 and perform a descriptive analysis of the vector population. METHODS The sampling was carried out using automatic HP light traps at all covered areas of the Venda Nova SD, in a total of eighteen light traps. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A simple environmental description was done for it area and Kernel estimation was used to infer vector density for each study site. FINDINGS A total of 2,427 sand fly specimens belonging to eight species and five genera were collected of which 95.3% were Lutzomyia longipalpis. The seasonal variation curve was delineated by this species. Lu. longipalpis was the most abundant at all collection points and in all months of the study, and exhibited a natural infection rate of 1.01% for Leishmania infantum and 1.77% for Leishmania braziliensis. MAIN CONCLUSIONS The results show the presence and adaptation of Lu. longipalpis to the anthropic environment of BH and reinforces its role as the main vector of L. infantum in the region.


Subject(s)
Humans , Animals , Male , Female , Dogs , Psychodidae/classification , Psychodidae/parasitology , Leishmaniasis/transmission , DNA, Protozoan/analysis , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Seasons , Brazil , Population Density
18.
Rev. bras. parasitol. vet ; 26(1): 17-27, Jan.-Mar. 2017. graf
Article in English | LILACS | ID: biblio-844132

ABSTRACT

Abstract This study aimed to detect parasites from Leishmania genus, to determine the prevalence of anti-Leishmania spp. antibodies, to identify circulating species of the parasite, and to determine epidemiological variables associated with infection in rats caught in urban area of Londrina, Paraná, Brazil. Animal capture was carried out from May to December 2006, serological and molecular methods were performed. DNA was extracted from total blood, and nested-PCR, targeting SSu rRNA from Leishmania genus, was performed in triplicate. The positive samples were sequenced twice by Sanger method to species determination. In total, 181 rodents were captured, all were identified as Rattus rattus and none showed clinical alterations. Forty-one of the 176 (23.3%) animals were positive for Leishmania by ELISA and 6/181 (3.3%) were positive by IFAT. Nine of 127 tested animals (7.1%) were positive by PCR; seven were identified as L. (L.) amazonensis, one as L. (L.) infantum. Four rats were positive using more than one test. This was the first description of synanthropic rodents naturally infected by L. (L.) amazonensis (in the world) and by L. (L.) infantum (in South Brazil). Regarding L. (L.) amazonensis, this finding provides new evidence of the urbanization of this etiological agent.


Resumo Esse estudo objetivou detectar parasitos do gênero Leishmania, determinar a prevalência de anticorpos anti-Leishmania spp., identificar as espécies circulantes do parasito e determinar variáveis epidemiológicas associadas com a infecção em ratos capturados em área urbana de Londrina, Paraná, Brazil. A captura dos animais ocorreu de maio a dezembro de 2006, métodos sorológicos e moleculares foram realizados. O DNA foi extraído do sangue total, uma nested-PCR cujo alvo foi o gene SSu rRNA do gênero Leishmania, foi realizado em triplicata. As amostras positivas foram sequenciadas duas vezes pelo método de Sanger para a determinação da espécie. No total, 181 roedores foram capturados, todos foram identificados como Rattus rattus e nenhum apresentou alterações clínicas. Quarenta e um dos 176 (23,3%) animais foram positivos no ELISA para Leishmania e 6/181 (3,3%) foram positivos na RIFI. Nove dos 127 animais testados (7,1%) foram positivos na PCR; sete foram identificadas como L. (L.) amazonensis, um como L. (L.) infantum. Quatro ratos foram positivos em mais de um teste. Essa é a primeira descrição de roedores sinantrópicos naturalmente infectados por L. (L.) amazonensis (no mundo) e por L. (L.) infantum (no Sul do Brasil). Com relação a L. (L.) amazonensis, esse resultado é uma nova evidência da urbanização desse agente etiológico.


Subject(s)
Animals , Rats/parasitology , Disease Reservoirs/veterinary , Antibodies, Protozoan/blood , Leishmania/isolation & purification , Urbanization , Brazil , Disease Reservoirs/parasitology , Leishmania infantum/isolation & purification , Leishmania infantum/immunology , Leishmania/immunology
19.
Mem. Inst. Oswaldo Cruz ; 112(2): 100-107, Feb. 2017. graf
Article in English | LILACS | ID: biblio-841760

ABSTRACT

BACKGROUND Leishmaniasis caused by Leishmania martiniquensis infection has been reported in human and domestic animals of Martinique Island, Germany, Switzerland, USA, Myanmar and Thailand. The peculiar clinical features of disseminated cutaneous and visceral forms co-existence render the urgent need of specific diagnostic tool to identify the natural sand fly vectors for effective prevention and control strategies. Loop-mediated isothermal amplification (LAMP) of 18S rRNA gene as well as polymerase chain reaction (PCR) of minicircle kinetoplast DNA gene (PCR-mkDNA) have never been applied to detect L. martiniquensis and L. siamensis in sand fly vectors. OBJECTIVE The present study was aimed to validate malachite green-LAMP (MG-LAMP) and PCR-mkDNA techniques to detect L. martiniquensis in sand fly vectors, compared with the conventional PCR of internal transcribed spacer 1 (PCR-ITS1). METHODS We compared the validity of LAMP of 18S rRNA gene and PCR-mkDNA, to PCR-ITS1 in simulation model of L. martiniquensis infection in Sergentomyia gemmea sand flies. Attributable to the sensitivity and specificity, PCR-mkDNA was consecutively applied to detect L. martiniquensis in 380 female sand fly individuals captured in the newly identified affected region of Lamphun Province, Thailand. FINDINGS AND MAIN CONCLUSIONS Results showed that PCR-mkDNA could detect at least one promastigote per sand fly, which was 10-time superior to LAMP and PCR-ITS1. In addition, PCR-mkDNA was more specific, able to differentiate L. martiniquensis from other viscerotropic Leishmania species, such as L. siamensis, L. (L.) donovani, and L. (L.) infantum. Consecutively, mass screening of L. martiniquensis in 380 female sand fly individuals by PCR-mkDNA was implemented in a new affected area of Thailand where a patient with leishmaniasis/HIV co-infection resides; however Leishmania DNA was undetected. In conclusion, PCR-mkDNA is a promising tool for molecular mass screening of L. martiniquensis infection in outbreak areas where several species of Leishmania and sand flies co-exist.


Subject(s)
Humans , Animals , Female , Leishmania/isolation & purification , Leishmania/classification , Leishmania/genetics , Thailand/epidemiology , DNA, Protozoan/genetics , DNA, Kinetoplast/genetics
20.
Mem. Inst. Oswaldo Cruz ; 112(1): 75-78, Jan. 2017. graf
Article in English | LILACS | ID: biblio-841757

ABSTRACT

Studies on the sandfly fauna to evaluate natural infection indexes are still limited in the Brazilian Amazon, a region with an increasing incidence of cutaneous leishmaniasis. Here, by using a multiplex polymerase chain reaction directed to Leishmania kDNA and hybridisation, we were able to identify L. (Viannia) subgenus in 12 out of 173 sandflies captured in the municipality of Rio Branco, Acre state, revealing a positivity of 6.94%. By sequencing the Leishmania 234 bp-hsp70 amplified products from positive samples, infection by L. (V.) braziliensis was confirmed in five sandflies: one Evandromyia saulensis, three Trichophoromyia auraensis and one Pressatia sp. The finding of L. (Viannia) DNA in two Ev. saulensis corresponds to the first record of possible infection associated with this sandfly. Moreover, our study reveals for the first time in Brazil, Th. auraensis and Pressatia sp. infected by L. (Viannia) parasites.


Subject(s)
Animals , Psychodidae/classification , Psychodidae/parasitology , Leishmaniasis, Cutaneous/transmission , Insect Vectors/classification , Insect Vectors/parasitology , Leishmania/isolation & purification , Leishmania/classification , Brazil , Multiplex Polymerase Chain Reaction
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