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Leishmaniasis are worldwide diseases that occur in 98 countries including Brazil, transmitted by the bite of female phlebotomines during blood feeding. In Brazil it is known that some species of sand flies as Lutzomyia longipalpis sensun latum (vector of Leishmania infantum chagasi), Lutzomyia flaviscutellata (vector of Leishmania (Leishmania) amazonensis) and Lutzomyia antunesi [suspected vector of Leishmania (Viannia) lindenbergi] are incriminated of transmitting the parasite Leishmania for the vertebrate host. The phlebotomine-parasite is mediated by the attachment of the promastigote lipophosphoglycan (LPG) to the midgut epithelium. However, another mechanism that is LPG-independent and mediated by N-acetyl-galactosamine (GalNAc) seems to occur in some species of phlebotomines that are classified as permissive. The aim of this study was to characterize the carbohydrate residues that, probably, play a role in parasite attachment to the midgut of phlebotomine from colony and field populations from the Brazilian Amazonian region. We observed the presence of GalNAc, mannose, galactose and GlcNAc in all phlebotomine species. A binding assay between L. (L.) amazonensis and L. i.chagasi to the midguts of different species of phlebotomines was performed. The attachment of both Leishmania and vector species suggests the presence of GalNAc on the midgut surfaces. Thus, these results suggested that GalNAc is a possible binding sites of Leishmania in sand flies from the Brazilian Amazonian region.
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Acetilgalactosamina/metabolismo , Carboidratos/análise , Glicoconjugados/metabolismo , Glicoesfingolipídeos/metabolismo , Leishmania/fisiologia , Psychodidae/parasitologia , Acetilglucosamina/metabolismo , Animais , Brasil , Feminino , Galactose/metabolismo , Manose/metabolismo , Psychodidae/química , Psychodidae/fisiologiaRESUMO
The present study aimed to assess different light sources for sampling phlebotomines (Diptera: Psychodidae) from Bosque Rodrigues Alves, a forested park surrounded by the urban area of Belém in the Brazilian Amazon. Centers for Disease Control traps, baited with blue, green, and warm white light-emitting diodes (LEDs), as test group, and incandescent light, as control group, were used. The electromagnetic spectra and luminous intensities of the light sources were characterized. Fractional vegetation cover at each sampling site was also estimated. Abundance, richness, rarefaction curves, Shannon and Simpson diversity indices, phlebotomines/trap/hour, and phlebotomines/trap/night were estimated and compared. The light sources of the test group presented greater luminous intensity than the control, but were similar to each other. There were no differences in vegetation cover at each site. A total of 1,346 phlebotomines comprising 11 species were sampled. The most abundant species were as follows: Nyssomyia antunesi (Coutinho, 1939), Trichophoromyia ubiquitalis (Mangabeira, 1942), Bichromomyia flaviscutellata (Mangabeira, 1942), and Th. brachipyga (Mangabeira, 1942). Light traps with LEDs had richness, abundance, and Shannon diversity indices similar to those obtained with incandescent light. The warm white LED had a higher Simpson's index than the other light sources. Phlebotomine responses to incandescent light were similar to those to LEDs in most analyses, confirming the applicability of these light sources as alternative devices for entomological surveillance. Low consumption ensures greater autonomy of the traps, providing better operability during fieldwork.
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Psychodidae , Animais , Psychodidae/fisiologia , Brasil , Parques Recreativos , Insetos Vetores , FlorestasRESUMO
The present work assessed the experimental susceptibility of Nyssomyia antunesi and Lutzomyia longipalpis to Leishmania (Viannia) lainsoni and L. (V.) lindenbergi. A L. (Leishmania) chagasi-Lu. longipalpis combination was used as a susceptible control. Wild-caught Ny. antunesi and laboratory-bred Lu. longipalpis were membrane-fed on blood with a 5 × 106/mL log-phase promastigote culture suspension and dissected on days 2 and 8 post-blood meal (pbm) for analysis focused on the assessment of parasitoses, as well as placement and promastigote morphotyping. Survival curves were constructed. In all combinations, promastigotes were observed on day 8 pbm. For both Leishmania species, in Lu. longipalpis, the presence of parasites was observed up to the stomodeal valve, while in Ny. antunesi, the presence of parasites was observed up to the cardia. There were no significant differences in parasitosis between L. (V.) lainsoni and L. (V.) lindenbergi in either Ny. antunesi or Lu. longipalpis. Six morphological promastigote forms were distinguished in Giemsa-stained gut smears. The survival curves of all combinations decreased and were affected differently by several Lu. longipalpis-parasite combinations, as well with Lu. longipalpis-uninfected blood. These findings stress Lu. longipalpis as experimentally susceptible to Leishmania spp. and suggest the putative susceptibility of Ny. antunesi to L. (V.) lainsoni and L. (V.) lindenbergi.
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The ground-dwelling invertebrate fauna from an urban park in Belém, Amazonian Brazil, with particular reference to the subfamily Phlebotominae (Diptera: Psychodidae), were characterized. Sampling was performed from March 2022 to May 2023, with 10 emergence traps installed in 2 microhabitats, 5 in each 1: "M1," which included surrounding (up to 1.5â m) trees with tabular roots, and "M2," which included no trees with tabular roots. Invertebrates trapped in adhesive papers were assessed on 2 occasions/cycles (D21/D42). During 10 sampling cycles (10 traps/cycleâ =â 100 samples), 6,490 invertebrates were captured (M1, nâ =â 4,203; M2, nâ =â 2,287) and classified into 5 classes and 21 orders, with Diptera (nâ =â 2,309; 35.6%) being the most abundant. Twenty-nine specimens of the following phlebotomine species were captured: Nyssomyia antunesi (M1, nâ =â 10; M2, nâ =â 3), Trichophoromyia ubiquitalis (M1, nâ =â 6; M2, nâ =â 1), Th. brachipyga (M1, nâ =â 0; M2, nâ =â 2), Bichromomyia flaviscutellata (M1, nâ =â 2; M2, nâ =â 1) and 4 unidentified specimens (M1, nâ =â 2; M2, nâ =â 2). The male/female ratio was 1.08. Fractional vegetation cover was compared, and the physiochemical characteristics of the soil were compared between the microhabitats. Only temperature showed significant differences. A weak positive correlation was found between phlebotomines and other dipterans and between temperature and the amount of organic matter in the soil. Both sampled microhabitats were shown to be suitable for the development and maintenance of different invertebrates, mainly dipterans. The composition of ground-emerging phlebotomine species was similar to that previously surveyed with light traps, including species associated with the transmission of Leishmania spp.
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BACKGROUND: A cohort study for 2 years period analysed the prevalence, incidence and clinical-immunological features of canine Leishmania (L.) chagasi-infection in 316 mongrel dogs in a visceral leishmaniasis-endemic area in Pará State, Brazil. OBJECTIVE/METHODS: Diagnosis of infection was performed by the indirect fluorescent antibody test (IFAT-IgG), the leishmanin skin test (LST) and a parasite search (from the popliteal lymph node aspiration) at the beginning of the study and at 6, 12 and 24 months intervals. RESULTS: IFAT/LST revealed three immune profiles of infection: (I) IFAT(+) /LST(-) (81), (II) IFAT(-) /LST(+) (17) and (III) IFAT(+) /LST(+) (13). Prevalence of profiles I, II and III were 25.6, 5.4 and 4.1%, and an overall prevalence 35.1%. Incidence of profiles I, II and III were 5.4, 0.3 and 0.0%, and an overall incidence 5.7% dogs per month. Incidence at the age ranges <1 year, ≥1 year, <7 years and ≥7 years evidenced a highest rate in the age range <1 year (6.6% dogs per month). Parasitological diagnosis was positive in 19% dogs at the prevalence (85.7% profile I), and in 11% at the incidence (100% profile I). The clinical picture of 179 infected dogs showed 145 (81%) of profile I (82% subclinical); 21 (11.7%) of profile II (100% subclinical); and 13 (7.3%) of profile III (84.6% subclinical). Conversion from subclinical to sick dogs was higher (p < 0.05) in profile I (40.2%) than in profiles II (5.8%) and III (9%). Immunological conversion showed that only 3.2% of profile I dogs (prevalence) converted to LST(+) (two at the end of the first 6 months and 1 after 24 months), while 82.3% of profile II dogs converted to IFAT(+) (11 in the first 6 months, whereas three after 12 months). A 100% death rate was observed in dogs from profile I alone. CONCLUSION: These results reinforce the need of adopting preventive strategies against CVL as early as in the first semester of the dog's life.
Assuntos
Doenças do Cão , Leishmaniose Visceral , Humanos , Cães , Animais , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Brasil/epidemiologia , Estudos de Coortes , Prevalência , Incidência , Doenças do Cão/diagnósticoRESUMO
Individuals infected with Leishmania (L.) chagasi may present different asymptomatic and symptomatic stages of infection, which vary in the clinical-immunological profiles that can be classified as asymptomatic infection (AI), subclinical resistant infection (SRI), indeterminate initial infection (III), subclinical oligosymptomatic infection (SOI), and symptomatic infection (SI) (=American visceral leishmaniasis, AVL). However, little is known about the molecular differences between individuals having each profile. Here, we performed whole-blood transcriptomic analyses of 56 infected individuals from Pará State (Brazilian Amazon), covering all five profiles. We then identified the gene signatures of each profile by comparing their transcriptome with those of 11 healthy individuals from the same area. Symptomatic individuals with SI (=AVL) and SOI profiles showed higher transcriptome perturbation when compared to those asymptomatic III, AI and SRI profiles, suggesting that disease severity may be associated with greater transcriptomic changes. Although the expression of many genes was altered on each profile, very few genes were shared among the profiles. This indicated that each profile has a unique gene signature. The innate immune system pathway was strongly activated only in asymptomatic AI and SRI profiles, suggesting the control of infection. In turn, pathways such as MHC Class II antigen presentation and NF-kB activation in B cells seemed to be specifically induced in symptomatic SI (=AVL) and SOI profiles. Moreover, cellular response to starvation was down-regulated in those symptomatic profiles. Overall, this study revealed five distinct transcriptional patterns associated to the clinical-immunological (symptomatic and asymptomatic) profiles of human L. (L.) chagasi-infection in the Brazilian Amazon.
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BACKGROUND: The aims of the present study were to evaluate and compare the efficacy of blood-feeding in phlebotomines through industrially processed membranes from the small intestine of pigs (used for the production of commercial sausages) and the skin of euthanized chicks. METHODS: Laboratory-bred Lutzomyia longipalpis and different field-caught phlebotomine species were subjected to the artificial feeding systems under similar conditions. Paired tests were performed using the control (skin from euthanized chicks) and test membranes (pig small intestine). The feeding rates were compared by paired t-test, and Pearson correlation was used to examine the relationship between the thickness of the membranes and feeding rate. RESULTS: The feeding rate was greater with the test membrane than with the control membrane for L. longipalpis (t-test, t = -3.3860, P = 0.0054) but not for the most frequent field-caught species, Nyssomyia antunesi (t-test, t = 0.7746, P = 0.4535). The average thicknesses of the control and test membranes were 184 ± 83 µm and 34 ± 12 µm, respectively (Mann-Whitney U-test, U = 0.00, Z = 2.8823, P = 0.0039); however, there was no correlation between feeding rate and membrane thickness. A moderate positive correlation was observed between the number of phlebotomines that fed and the total number of phlebotomines in the cage for each type of membrane and for each species. CONCLUSIONS: The test membrane is a viable alternative for the artificial blood-feeding of phlebotomines, and is thus a potential substitute for the skin of animals that are euthanized for this purpose. Feeding rate was independent of membrane thickness.
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Substitutos Sanguíneos , Psychodidae , Animais , Suínos , Insetos Vetores , Apoio Nutricional , BrasilRESUMO
Present work aimed to identify blood feeding sources and attempt to detect Leishmania DNA in Nyssomyia antunesi, suspected vector of Leishmania sp., from a park in the urban center of Belém, the capital of Pará State, in the Brazilian Amazon. Entire bodies and gut contents of Ny. antunesi engorged females, previously captured in the urban park with Centers for Disease Control (CDC) light traps and aspiration on tree bases, were subjected to Leishmania and vertebrate DNA detection through amplification of the Leishmania mini-exon and vertebrate cytochrome b (cyt b) gene regions, respectively. The quality of DNA extraction from entire bodies was ensured through amplification of the dipteran cyt b region. The vertebrate cyt b amplicons were sequenced and compared with those available on GenBank. A maximum likelihood phylogenetic tree was constructed to assess the clustering patterns of these sequences. Leishmania DNA was not detected. The sequences of 13 vertebrate cyt b amplicons were considered informative, exhibiting similarity and clustering with the following six vertebrate species: Dasyprocta leporina (1), Cuniculus paca (1), Tamandua tetradactyla (4), Choloepus didactylus (4), Pteroglossus aracari aracari (2), Homo sapiens (1). The samples of D. leporina and C. paca were obtained from the CDC canopy, whereas the others were by aspiration from tree bases. The present results revealed the eclectic and opportunist blood-feeding behavior of Ny. antunesi, with birds and mammals, these last ones acting as potential reservoirs for Leishmania species, distributed throughout the vertical forest strata.
Assuntos
Kinetoplastida , Leishmania , Psychodidae , Animais , Brasil , Citocromos b/genética , Feminino , Insetos Vetores , Leishmania/genética , Mamíferos , FilogeniaRESUMO
This was an open cohort prospective study (2016−2018) that analyzed the prevalence and incidence rates of human Leishmania (L.) infantum chagasi-infection and the evolution of their clinical-immunological profiles in distinct urban and rural scenarios of American visceral leishmaniasis (AVL) in Pará State, in the Brazilian Amazon. These infection profiles were based on species-specific DTH/IFAT-IgG assays and clinical evaluation of infected individuals, comprising five profiles: three asymptomatic, Asymptomatic Infection [AI], Subclinical Resistant Infection [SRI], and Indeterminate Initial Infection [III]; and two symptomatic, Subclinical Oligosymptomatic Infection [SOI] and Symptomatic Infection [SI = AVL]. The two distinct scenarios (900 km away) were the urban area of Conceição do Araguaia municipality and the rural area of Bujaru municipality in the southeast and northeast of Pará State. Human populations were chosen based on a simple convenience sampling design (5−10% in each setting), with 1723 individuals (5.3%) of the population (32,464) in the urban area and 1568 individuals (8.9%) of the population (17,596) in the rural one. A serological survey (IFAT-IgG) of canine infection was also performed in both scenarios: 195 dogs in the urban area and 381 in the rural one. Prevalence and incidence rates of human infection were higher in the urban area (20.3% and 13.6/100 person-years [py]) than in the rural setting (14.1% and 6.8/100-py). The AI profile was the most prevalent and incident in both urban (13.4% and 8.1/100-py) and rural (8.3% and 4.2/100-py) scenarios, but with higher rates in the former. An III profile case evolved to SOI profile after four weeks of incubation and another to SI (=AVL) after six. The prevalence of canine infection in an urban setting (39.2%) was also higher (p < 0.05) than that (32%) in the rural zone. AVL urbanization in Pará State, in the Brazilian Amazon, has led to infection rates significantly higher than those in rural sites, requiring more intense control measures.
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Visceral leishmaniasis (VL), also known as kala-azar, is an anthropozoonotic disease affecting human populations on five continents. Aetiologic agents belong to the Leishmania (L.) donovani complex. Until the 1990s, three leishmanine parasites comprised this complex: L. (L.) donovani Laveran & Mesnil 1903, L. (L.) infantum Nicolle 1908, and L. (L.) chagasi Lainson & Shaw 1987 (=L. chagasi Cunha & Chagas 1937). The VL causal agent in the New World (NW) was previously identified as L. (L.) chagasi. After the development of molecular characterization, however, comparisons between L. (L.) chagasi and L. (L.) infantum showed high similarity, and L. (L.) chagasi was then regarded as synonymous with L. (L.) infantum. It was, therefore, suggested that L. (L.) chagasi was not native to the NW but had been introduced from the Old World by Iberian colonizers. However, in light of ecological evidence from the NW parasite's enzootic cycle involving a wild phlebotomine vector (Lutzomyia longipalpis) and a wild mammal reservoir (the fox, Cerdocyon thous), we have recently analyzed by molecular clock comparisons of the DNA polymerase alpha subunit gene the whole-genome sequence of L. (L.) infantum chagasi of the most prevalent clinical form, atypical dermal leishmaniasis (ADL), from Honduras (Central America) with that of the same parasite from Brazil (South America), as well as those of L. (L.) donovani (India) and L. (L.) infantum (Europe), which revealed that the Honduran parasite is older ancestry (382,800 ya) than the parasite from Brazil (143,300 ya), L. (L.) donovani (33,776 ya), or L. (L.) infantum (13,000 ya). In the present work, we have now amplified the genomic comparisons among these leishmanine parasites, exploring mainly the variations in the genome for each chromosome, and the number of genomic SNPs for each chromosome. Although the results of this new analysis have confirmed a high genomic similarity (~99%) among these parasites [except L. (L.) donovani], the Honduran parasite revealed a single structural variation on chromosome 17, and the highest frequency of genomic SNPs (more than twice the number seen in the Brazilian one), which together to its extraordinary ancestry (382,800 ya) represent strong evidence that L. (L.) chagasi/L. (L.) infantum chagasi is, in fact, native to the NW, and therefore with valid taxonomic status. Furthermore, the Honduran parasite, the most ancestral viscerotropic leishmanine parasite, showed genomic and clinical taxonomic characteristics compatible with a new Leishmania species causing ADL in Central America.
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The clinical-immunological spectrum of human Leishmania (L.) infantum chagasi-infections in the Brazilian Amazon has been defined using DTH/IFAT-IgG immune assays and the clinical statuses of infected individuals, revealing five profiles: three asymptomatic [Asymptomatic Infection (AI), Subclinical Resistant Infection (SRI), and Indeterminate Initial Infection (III)], and two symptomatic profiles [Subclinical Oligosymptomatic Infection (SOI) and Symptomatic Infection (SI = American visceral leishmaniasis/AVL)]. We evaluated the diagnostic potential of urine qPCR over the entire spectrum of infection. Resine Instagene Matrix® was used for DNA extraction from urinary sediment, with amplification carried out using SYBR® Green Taq with the RV1 and RV2 primers. We examined urine samples from 151 individuals from an endemic area of AVL in Pará State in the Brazilian Amazon, including: 91 (60.3%) with diagnoses of previous infections [13 (14.3%) sharing the AI profile, 13 (14.3%) with the SRI profile, 43 (47.2%) with III, 12 (13.2%) with SI (treated AVL), and 10 (11%) with SI (untreated AVL)]; sixty (39.7%) were DTH(-)/IFAT-IgG(-) (the uninfected group). The urine qPCR was positive in 61.5% of both the AI and SRI profiles, 65% of the III profile, 50% of treated AVL, 100% of untreated AVL, and 6.7% of the uninfected group. Those results confirmed the urine qPCR diagnosis in 100% of untreated AVL cases as well as in more than 60% of the cases with asymptomatic AI, SRI, and III profiles - indicating it as a promising tool for monitoring the evolution of human L. (L.) infantum chagasi-infections in endemic areas.
Assuntos
Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Assintomáticas , Brasil , Feminino , Humanos , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/urina , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Adulto JovemRESUMO
This work reports on the whole-genome sequencing of Leishmania infantum chagasi from Honduras (Central America) and Brazil (South America).
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The clinical-immunological spectrum of human Leishmania (L.) infantum chagasi-infection in Amazonian Brazil has recently been reviewed based on the combined use of the delayed-type hypersensitivity (DTH) and indirect fluorescence antibody test (IFAT-IgG/IgM), both with homologous L. (L.) infantum chagasi-antigens, and associated with the clinical evaluation of infected individuals. This diagnostic approach has allowed to identify the broadest clinical-immunological spectrum of human L. (L.) infantum chagasi-infection composed by five clinical-immunological profiles of infection: three asymptomatic, 1) Asymptomatic Infection (AI) [DTH+/++++, IFAT-], 2) Subclinical Resistant Infection (SRI) [DTH+/++++, IFAT+/++], and 3) Indeterminate Initial Infection (III) [DTH-, IFAT+/++], and two symptomatic ones, 4) Symptomatic Infection (SI) [=American visceral leishmaniasis - AVL] and, 5) Subclinical Oligosymptomatic Infection (SOI), both with the same immune profile [DTH-, IFAT+++/++++]. Herein, we confirm for the third time the preclinical diagnosis of AVL through IgM-antibody response in an early asymptomatic case of infection (profile III), a 17-year-old boy who evolved to AVL (=profile SI) six weeks after the initial infection diagnosis, confirming that the combined use of DTH and IFAT-(IgG/IgM) assays associated with the clinical evaluation of infected individuals is potentially useful for monitoring human L. (L.) infantum chagasi-infection in endemic areas as well as optimizing AVL control.
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In urban ecotourism parks, the life cycle of American cutaneous leishmaniasis (ACL) agents can remain established, where phlebotomines may comprise potential risks for visitors. The present study aimed to survey the phlebotomine fauna of a forest park 'Bosque Rodriques Alves-Jardim Botânico da Amazônia' (BRAJBA), in the urban area of Belém, Brazil. The park was monthly surveyed in 2018 using CDC light traps placed in ground and canopy strata. Leishmania spp. isolated from dissected females were characterized by polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP) analysis. Fluctuations in specimen capture were correlated with rainfall. Nyssomyia antunesi (Coutinho, 1939) was predominant for all surveyed ecotopes and capture methods in both areas. Females of Ny. antunesi resting on tree bases were observed attempting to bite researchers during early morning. One Bichromomyia flaviscutellata (Mangabeira, 1942) and one Trichophoromyia brachipyga (Mangabeira, 1942) were found naturally infected by flagellates. Only the strain from Th. brachipyga was isolated and characterized as Leishmania (Viannia) lainsoni Silveira, Shaw, Braga and Ishikawa, 1987. Monthly fluctuations of the three most abundant species, Ny. antunesi, Trichophoromyia ubiquitalis (Mangabeira, 1942) and Th. brachypiga, had statistically significant negative correlations with rainfall. The present study provided further information to better understand ACL ecology in the Belém urban area, where the urban parks surveyed appeared to offer potential risk of contracting the disease, thus requiring environmental management. These observations highlighted the need for including Ny. antunesi, Bi. flaviscutellata, Th. ubiquitalis, and Th. brachypiga in the priority list for continuous entomological surveillance.
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Leishmania/isolamento & purificação , Leishmaniose Cutânea/transmissão , Psychodidae/fisiologia , Animais , Brasil , Cidades , Insetos Vetores/parasitologia , Insetos Vetores/fisiologia , Parques Recreativos , Psychodidae/parasitologia , Especificidade da EspécieRESUMO
In the present study, we reported the natural infection by Leishmania sp. in a domestic cat, in which the amastigote forms of the parasite were observed within a lesion on its ear-tip. Fragment of the lesion was obtained and cultured in NNN medium, and PCR-RFLP analysis of the isolated sample was performed, which revealed that the profile was compatible with Leishmania (L.) amazonensis. This is the first proven case of a cat infected by L. (L.) amazonensis reported in Belém city, Pará state, northern Brazil.
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Alopurinol/uso terapêutico , Azitromicina/uso terapêutico , Doenças do Gato/diagnóstico , Leishmania mexicana/isolamento & purificação , Leishmaniose Cutânea/veterinária , Dermatopatias/veterinária , Tripanossomicidas/uso terapêutico , Animais , Brasil , Doenças do Gato/tratamento farmacológico , Doenças do Gato/parasitologia , Gatos , Diagnóstico Diferencial , Feminino , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Dermatopatias/diagnóstico , Dermatopatias/tratamento farmacológico , Dermatopatias/parasitologiaRESUMO
Males of cryptic or closely related species present great morphological variation in their genitalia, whereas females, such as those of the Chagasi Series of the Psychodopygus Mangabeira, 1941 genus, are more similar. Therefore, our aim was to study the fine structure of the male genitalia of five species of the Chagasi Series to better understand the variation in their morphology and its influence on the copulatory process. The sand fly species were captured in the following Brazilian states: Psychodopygus chagasi (Costa Lima, 1941) (Rondônia), Psychodopygus complexus (Mangabeira, 1941) (Tocantins), Psychodopygus squamiventris maripaensis (Floch & Abonnenc, 1946) (Amapá), Psychodopygus squamiventris squamiventris (Lutz & Neiva, 1912) (Amazonas), and Psychodopygus wellcomei Fraiha, Shaw & Lainson, 1971 (Pará and Ceará). Insects were stored in ethanol 70% (then dehydrated) and dry after they were sputtered with gold. The samples were observed under a scanning electron microscope. Microtrichiae, two types of trichoid sensilla, coeloconic and chaetic sensillae, were observed on the antenna of all species, with no difference between them. Only on the anepimeron of P. squamiventris squamiventris a modified 'racket'-like scale was observed. As for the male genitalia, the setae and structures of each species were fully described, such as the small setae on the paramere apex of the P. squamiventris subspecies, and the grooves present in this region and on the paramere lobe of P. complexus and P. wellcomei, which are impossible to observe with optic microscopy. New information is thus provided on the male genitalia, which can contribute to future bionomic studies of these species.
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Insetos Vetores/ultraestrutura , Psychodidae/ultraestrutura , Animais , Brasil , Genitália Masculina/ultraestrutura , Leishmaniose Cutânea , MasculinoRESUMO
INTRODUCTION: American cutaneous leishmaniasis (ACL) is regarded as a public health problem in the Oiapoque basin, between Brazil and French Guiana. METHODS: Data on ACL occurrence/epidemiological profile and etiology were sourced from Brazilian health services and a reference laboratory. Rainfall correlation was also analyzed. RESULTS: Majority of the ACL cases were observed in adult men working as gold miners. ACL incidence peaks appeared to be linked to periods 2 months after the dry season. Migratory flow was found to be a non-negligible complicating factor in epidemiological surveillance. CONCLUSIONS: Binational strategies are required to minimize exposure for high-risk populations.
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Leishmaniose Cutânea/epidemiologia , Adulto , Idoso , Brasil/epidemiologia , Feminino , Guiana Francesa/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estações do Ano , Adulto JovemRESUMO
Trichophoromyia iorlandobaratai sp. n. Vasconcelos dos Santos, Santos Neto, Sánchez Uzcátegui & Galardo is described and illustrated on the basis of male specimens collected in the municipality of Itaituba, Pará State, Brazilian Amazonia. This species can be differentiated from other morphologically similar species within Trichophoromyia by means of the male characters such as the ratio between the aedeagal ducts/sperm pump, shape and distribution of setae in the gonocoxite, and particularly the distinct shape of paramere.
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Psychodidae/anatomia & histologia , Psychodidae/classificação , Animais , Brasil , MasculinoRESUMO
A major challenge of eco-epidemiology is to determine which factors promote the transmission of infectious diseases and to establish risk maps that can be used by public health authorities. The geographic predictions resulting from ecological niche modelling have been widely used for modelling the future dispersion of vectors based on the occurrence records and the potential prevalence of the disease. The establishment of risk maps for disease systems with complex cycles such as cutaneous leishmaniasis (CL) can be very challenging due to the many inference networks between large sets of host and vector species, with considerable heterogeneity in disease patterns in space and time. One novelty in the present study is the use of human CL cases to predict the risk of leishmaniasis occurrence in response to anthropogenic, climatic and environmental factors at two different scales, in the Neotropical moist forest biome (Amazonian basin and surrounding forest ecosystems) and in the surrounding region of French Guiana. With a consistent data set never used before and a conceptual and methodological framework for interpreting data cases, we obtained risk maps with high statistical support. The predominantly identified human CL risk areas are those where the human impact on the environment is significant, associated with less contributory climatic and ecological factors. For both models this study highlights the importance of considering the anthropogenic drivers for disease risk assessment in human, although CL is mainly linked to the sylvatic and peri-urban cycle in Meso and South America.
Assuntos
Ecologia , Ecossistema , Florestas , Leishmaniose Cutânea/epidemiologia , Guiana Francesa/epidemiologia , Humanos , Prevalência , Estações do Ano , América do Sul/epidemiologiaRESUMO
In the border region between Brazil and French Guiana, American cutaneous leishmaniasis is a worrisome public health issue, and entomological studies are required there to better identify classical and putative emerging transmission patterns. The present study aimed to detect and characterize Leishmania DNA in the phlebotomine population of Oiapoque (Amapá State, Brazil). Phlebotomines were captured in anthropized and wild environments in the outskirts of Oiapoque municipality, using CDC light traps installed in vertical (ground/canopy level) and horizontal (peridomicile/extradomicile/forest-edge/forest) strata. Captured specimens were identified according to their morphology. Females were processed for Leishmania DNA detection and characterization using a multiplex polymerase chain reaction targeting kinetoplast DNA (kDNA) and the phlebotomine cacophony gene. The kDNA positive samples were characterized by cloning and sequencing the Leishmania 234 bp-hsp70 gene. Among the 3957 phlebotomine specimens captured, 26 pooled female samples were positive for Leishmania (Viannia) spp. DNA. Sequencing analysis allowed species-specific identification of L. (V.) braziliensis DNA in Trichophoromyia ininii, Bichromomyia flaviscutellata, Nyssomyia umbratilis, and Evandromyia infraspinosa, and L. (V.) guyanensis DNA in Ny. umbratilis. A pooled sample of Ny. umbratilis was positive for both L. (V.) braziliensis and L. (V.) guyanensis DNA. The present study provided additional information regarding ACL ecology in Oiapoque, highlighting the presence of L. (V.) braziliensis DNA in different phlebotomine species. The epidemiological implications of these findings and the determinant incrimination of L. (V.) braziliensis as proven vectors in that region must be clarified. In this regard, studies on Leishmania spp. infection and suggestive anthropophilic behavior of associated phlebotomines need to be prioritized in entomological surveillance.