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1.
PLoS Negl Trop Dis ; 15(8): e0009676, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34411102

RESUMEN

The scarce information about breeding sites of phlebotomines limits our understanding of the epidemiology of tegumentary leishmaniasis. Identifying the breeding sites and seasons of immature stages of these vectors is essential to propose prevention and control strategies different from those targeting the adult stage. Here we identified the rural breeding environments of immature stages of Ny. whitmani, vector species of Leishmania braziliensis in the north of Misiones province, Argentina; then we determined and compared the environmental and structural characteristics of those sites. We also identified the season of greatest emergence and its relationship with adult abundance. During a first collection period, between 28 and 48 emergence traps were set continuously for 16 months in six environments of the farm peridomicile and domicile: below house, chicken shed, experimental chicken shed, forest edge, pigsty and under fruit tree. Traps were checked and rotated every 40 nights. A total of 146 newly emerged individuals were collected (93.8% of them were Ny. whitmani), totaling an effort of 23,040 emergence trap-nights. The most productive environments were chicken shed and below house, and the greatest emergence was recorded in spring and summer. During a second collection period, emergence traps and light traps for adult capture were placed in the chicken shed and below house environments of eight farms. Emergence traps were active continuously during spring, summer, and early autumn. Environmental and structural characteristics of each environment were recorded. A total of 84 newly emerged phlebotomines (92.9% Ny. whitmani; 72,144 emergence trap-nights) and 13,993 adult phlebotomines (147 light trap-nights) were recorded in the chicken shed and below house environments. A positive correlation was also observed between trap success of newly emerged phlebotomines and of adults after 120 days. A high spatial variability was observed in the emergence of Ny. whitmani, with the number of newly emerged individuals being highest in soils of chicken sheds with the highest number of chickens and closest to forest edge. Moreover, below house was found to be as important as chicken sheds as breeding sites of Ny. whitmani. Management of the number of chickens in sheds, soil moisture and pH, and the decision of where to localize the chicken sheds in relation to the houses and the forest edge, might contribute to reduce the risk of human vector exposure and transmission of Leishmania.


Asunto(s)
Insectos Vectores/fisiología , Leishmaniasis/epidemiología , Psychodidae/fisiología , Animales , Argentina/epidemiología , Cruzamiento , Pollos , Femenino , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/parasitología , Leishmania/fisiología , Leishmaniasis/parasitología , Leishmaniasis/transmisión , Masculino , Psychodidae/crecimiento & desarrollo , Psychodidae/parasitología , Estaciones del Año
2.
J Med Entomol ; 58(4): 1917-1925, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-33822113

RESUMEN

Studies on experimental sand fly infection require the availability of colonies and laboratory conditions. In Brazil, Lutzomyia longipalpis (Diptera: Psychodidae) (Lutz and Neiva 1912) is responsible for the highest infection rates by Leishmania spp. and this species is one of the most suitable species for laboratory colonization. In this study, we describe a method for growing Lu. longipalpis in laboratory conditions (10 generations) from natural populations sampled from a region of high endemicity for visceral leishmaniasis in the state of Maranhão, Northeastern Brazil. Using two methods (individualized or grouped females), the colony's highest productivity occurred in the first four generations, where all stages presented with high frequency. Nonviable eggs represented more than 50% of the total eggs produced by engorged females, while pupae were more resistant to fungal contamination, with a mortality rate of only 2%. In both methods, there was a predominance of female emergence; however, the ratio between males and females did not show significant differences, IF (P = 0.8023) and GF (P = 0.1831). Using the method of individualized females, the F4 generation took the longest to appear (234 d; 64 ± 57 d); by grouped females, F3 took the longest to appear (102 d; 47 ± 20 d). This method provides sufficient numbers of insects to perform vector competence tests for Leishmania spp. that cause the cutaneous form of leishmaniasis, usually found in Lu. longipalpis sampled from the study location.


Asunto(s)
Insectos Vectores/crecimiento & desarrollo , Psychodidae/crecimiento & desarrollo , Animales , Bioensayo/métodos , Fertilidad , Laboratorios , Leishmania , Leishmaniasis/transmisión , Psychodidae/parasitología , Razón de Masculinidad
3.
Infect Immun ; 89(2)2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33139381

RESUMEN

Leishmania, the causative agent of leishmaniasis, is an intracellular pathogen that thrives in the insect gut and mammalian macrophages to complete its life cycle. Apart from temperature difference (26 to 37°C), it encounters several harsh conditions, including oxidative stress, inflammatory reactions, and low pH. Heat shock proteins (HSPs) play essential roles in cell survival by strategically reprogramming cellular processes and signaling pathways. HSPs assist cells in multiple functions, including differentiation, adaptation, virulence, and persistence in the host cell. Due to cyclical epidemiological patterns, limited chemotherapeutic options, drug resistance, and the absence of a vaccine, control of leishmaniasis remains a far-fetched dream. The essential roles of HSPs in parasitic differentiation and virulence and increased expression in drug-resistant strains highlight their importance in combating the disease. In this review, we highlighted the diverse physiological importance of HSPs present in Leishmania, emphasizing their significance in disease pathogenesis. Subsequently, we assessed the potential of HSPs as a chemotherapeutic target and underlined the challenges associated with it. Furthermore, we have summarized a few ongoing drug discovery initiatives that need to be explored further to develop clinically successful chemotherapeutic agents in the future.


Asunto(s)
Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Supervivencia Celular/fisiología , Proteínas de Choque Térmico/efectos adversos , Proteínas de Choque Térmico/uso terapéutico , Leishmania/crecimiento & desarrollo , Leishmaniasis/fisiopatología , Leishmaniasis/terapia , Animales , Humanos , Insectos Vectores/crecimiento & desarrollo , Psychodidae/crecimiento & desarrollo
4.
BMC Genomics ; 21(1): 608, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32887545

RESUMEN

BACKGROUND: Sand flies are the vectors of Leishmania parasites. To develop in the sand fly midgut, Leishmania multiplies and undergoes various stage differentiations giving rise to the infective form, the metacyclic promastigotes. To determine the changes in sand fly midgut gene expression caused by the presence of Leishmania, we performed RNA-Seq of uninfected and Leishmania infantum-infected Lutzomyia longipalpis midguts from seven different libraries corresponding to time points which cover the various Leishmania developmental stages. RESULTS: The combined transcriptomes resulted in the de novo assembly of 13,841 sand fly midgut transcripts. Importantly, only 113 sand fly transcripts, about 1%, were differentially expressed in the presence of Leishmania parasites. Further, we observed distinct differentially expressed sand fly midgut transcripts corresponding to the presence of each of the various Leishmania stages suggesting that each parasite stage influences midgut gene expression in a specific manner. Two main patterns of sand fly gene expression modulation were noted. At early time points (days 1-4), more transcripts were down-regulated by Leishmania infection at large fold changes (> 32 fold). Among the down-regulated genes, the transcription factor Forkhead/HNF-3 and hormone degradation enzymes were differentially regulated on day 2 and appear to be the upstream regulators of nutrient transport, digestive enzymes, and peritrophic matrix proteins. Conversely, at later time points (days 6 onwards), most of the differentially expressed transcripts were up-regulated by Leishmania infection with small fold changes (< 32 fold). The molecular functions of these genes have been associated with the metabolism of lipids and detoxification of xenobiotics. CONCLUSION: Overall, our data suggest that the presence of Leishmania produces a limited change in the midgut transcript expression profile in sand flies. Further, Leishmania modulates sand fly gene expression early on in the developmental cycle in order to overcome the barriers imposed by the midgut, yet it behaves like a commensal at later time points where a massive number of parasites in the anterior midgut results only in modest changes in midgut gene expression.


Asunto(s)
Mucosa Intestinal/metabolismo , Leishmania/patogenicidad , Psychodidae/genética , Transcriptoma , Animales , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Hormonas de Insectos/genética , Hormonas de Insectos/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Insectos Vectores/genética , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/parasitología , Psychodidae/crecimiento & desarrollo , Psychodidae/parasitología
5.
PLoS Negl Trop Dis ; 14(5): e0008324, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32463829

RESUMEN

Local anomalies in rainfall and temperature induced by El Niño and La Niña episodes could change the structure of the vector community. We aimed to estimate the effect of the El Niño-La Niña cycle in the potential distribution of cutaneous leishmaniasis (CL) vector species in Colombia and to compare the richness of the vectors with the occurrence of CL in the state of Norte de Santander. The potential distributions of four species were modeled using a MaxEnt algorithm for the following episodes: La Niña 2010-2011, Neutral 2012-2015 and El Niño 2015-2016. The relationship between the potential richness of the vectors and the occurrence of CL in Norte de Santander was evaluated with a log-binomial regression model. During the El Niño 2015-2016 episode, Lutzomyia ovallesi and Lutzomyia panamensis increased their distribution into environmentally suitable areas, and three vector species (Lutzomyia gomezi, Lutzomyia ovallesi and Lutzomyia panamensis) showed increases in the range of their altitudinal distribution. During the La Niña 2010-2011 episode, a reduction was observed in the area suitable for occupation by Lutzomyia gomezi and Lutzomyia spinicrassa. During the El Niño 2015-2016 episode, the occurrence of at least one CL case was related to a higher percentage of rural localities showing a richness of vectors = 4. The anomalies in rainfall and temperature induced by the episodes produced changes in the potential distribution of CL vectors in Colombia. In Norte de Santander, during Neutral 2012-2015 and El Niño 2015-2016 episodes, a higher probability of at least one CL case was related to a higher percentage of areas with a greater richness of vectors. The results help clarify the effect of the El Niño-La Niña cycle in the dynamics of CL in Colombia and emphasize the need to monitor climate variability to improve the prediction of new cases.


Asunto(s)
El Niño Oscilación del Sur , Insectos Vectores/crecimiento & desarrollo , Leishmaniasis Cutánea/epidemiología , Psychodidae/crecimiento & desarrollo , Animales , Colombia/epidemiología , Humanos
7.
Turkiye Parazitol Derg ; 43(3): 152-154, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31502807

RESUMEN

Urogenital myiasis is a parasitic infestation caused by larvae of Psychoda spp. and it is very rare in humans. A 10- year old female was presented with urogenital myiasis and 4th stage Larvae of Psychoda albipennis (Diptera: Psychodidae) were found in urine. The patient was complained of painful sensation, discomfort and burning while urination. Urinary tract antiseptics were prescribed for the patient and advised to drink plenty of water for hydration. Local health authorities should take proper measures to maintain hygienic conditions for the people under risk.


Asunto(s)
Enfermedades Urogenitales Femeninas/parasitología , Miasis/parasitología , Psychodidae/clasificación , Animales , Antiinfecciosos Urinarios/uso terapéutico , Niño , Ingestión de Líquidos , Femenino , Enfermedades Urogenitales Femeninas/terapia , Humanos , Larva , Libia , Miasis/terapia , Psychodidae/crecimiento & desarrollo , Orina/parasitología
8.
PLoS Negl Trop Dis ; 13(8): e0007667, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31425506

RESUMEN

BACKGROUND: Ochollo is a village in southern Ethiopia burdened with cutaneous leishmaniasis (CL), where Phlebotomus pedifer is the only vector for Leishmania aethiopica and hyraxes are confirmed reservoir hosts. A detailed description of the different players of transmission, and the ecology and seasonality of the vector needs to be established in order to accomplish efficient control programs. METHODS AND FINDINGS: Between March 2017 and February 2018, a monthly sandfly collection was carried out in different habitats and records of temperature and humidity were taken. Rodents and hyraxes were trapped in the dry and wet season. All samples were screened for Leishmania kinetoplast DNA (kDNA). Positive samples were further processed for determination of the Leishmania species and the species of the sandfly/small mammal that was found infected. Additionally, the species of 400 sandfly specimens from different habitats and seasons was identified. 17,190 Sergentomyia and Phlebotomus sandflies were caught and showed an overall kDNA prevalence of 2.6%, all were L. aethiopica infections only found in P. pedifer. The overall sandfly and P. pedifer abundance peaked in the dry season and was negatively correlated with the %RH. The kDNA prevalence varied over the months and was negatively correlated with the temperature. Total sandfly abundance did not differ between the sampled habitats, but P. pedifer was the distinct predominant species only in caves. Moreover, significantly more infected sandflies were found in caves. Only 1/192 rodents were kDNA positive, while 20.0% (5/25) of Heterohyrax brucei were found infected. CONCLUSIONS: This study suggests that caves may be a source of multiplication of the infection. If an outdoor control program would be considered, it would be useful to focus on caves in the wet season, when the sandfly abundance is lowest. The captured rodent species appear not important for transmission and the contribution of hyraxes in transmission should be further investigated.


Asunto(s)
ADN Protozoario/análisis , Reservorios de Enfermedades , Vectores de Enfermedades , Damanes/parasitología , Leishmania/genética , Leishmaniasis Cutánea/epidemiología , Psychodidae/parasitología , Animales , ADN Protozoario/genética , Transmisión de Enfermedad Infecciosa , Etiopía/epidemiología , Femenino , Humanos , Humedad , Leishmaniasis Cutánea/transmisión , Masculino , Carga de Parásitos , Prevalencia , Psychodidae/crecimiento & desarrollo , Estaciones del Año , Temperatura
9.
Sci Rep ; 9(1): 2469, 2019 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-30792449

RESUMEN

Sand flies are responsible for the transmission of leishmaniasis, a neglected tropical disease claiming more than 50,000 lives annually. Leishmaniasis is an emerging health risk in tropical and Mediterranean countries as well as temperate regions in North America and Europe. There is an increasing demand for predicting population dynamics and spreading of sand flies to support management and control, yet phenotypic diversity and complex environmental dependence hamper model development. Here, we present the principles for developing predictive species-specific population dynamics models for important disease vectors. Based on these principles, we developed a sand fly population dynamics model with a generic structure where model parameters are inferred using a surveillance dataset collected from Greece and Cyprus. The model incorporates distinct life stages and explicit dependence on a carefully selected set of environmental variables. The model successfully replicates the observations and demonstrates high predictive capacity on the validation dataset from Turkey. The surveillance datasets inform about biological processes, even in the absence of laboratory experiments. Our findings suggest that the methodology can be applied to other vector species to predict abundance, control dispersion, and help to manage the global burden of vector-borne diseases.


Asunto(s)
Leishmaniasis/transmisión , Vigilancia de la Población/métodos , Psychodidae/crecimiento & desarrollo , Animales , Teorema de Bayes , Clima , Chipre/epidemiología , Vectores de Enfermedades , Grecia/epidemiología , Leishmaniasis/epidemiología , Dinámica Poblacional , Psychodidae/parasitología , Procesos Estocásticos , Turquía
10.
Geospat Health ; 13(2)2018 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-30451468

RESUMEN

Historically leishmaniasis is most prevalent in established urban centres but this research shows that refugees and, most significantly, internally displaced persons are now commonly in areas characterized by the presence of fly habitats potentially leading to higher prominence of Leishmania infection. Areas engulfed by the Syrian civil war has thus caused the dispersal of humans into previously unpopulated areas amid habitats of the sand fly Phlebotomus papatasi that hosts the parasite Leishmania. The addition of new places of exposure to this disease add to difficulties with respect to diagnosis as well as provision of care and treatment. We used geospatial methodology adapting it to remotely identifying and analyzing sand fly habitats with the aim of measuring how common it is. Our methodology helps avoid the issue of resolution in satellite imagery by measuring likelihood rather than strictly known locations. We followed up this information with spatial analysis identifying which civilian populations are most prone to sand fly exposure, and therefore leishmaniasis, due to their geographical situation. Our results suggest that those most likely to be exposed to Leishmania are internally displaced persons, those camps less likely to receive medical relief and typically having temporary residents migrating elsewhere.


Asunto(s)
Insectos Vectores/crecimiento & desarrollo , Leishmaniasis/epidemiología , Psychodidae/crecimiento & desarrollo , Refugiados , Imágenes Satelitales , Análisis Espacial , Animales , Conflictos Armados , Ecosistema , Humanos , Estaciones del Año , Siria/epidemiología
11.
PLoS Negl Trop Dis ; 12(10): e0006846, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30273402

RESUMEN

BACKGROUND: Visceral leishmaniasis (VL) in the Indian subcontinent is a fatal disease if left untreated. Between 1994 to 2013, the Ministry of Health of Bangladesh reported 1,09,266 cases of VL and 329 VL related deaths in 37 endemic districts. Indoor residual spraying (IRS) using dichlorodiphenyltrichloroethane (DDT) was used by the national programme in the 1960s to control malaria. Despite findings of research trials demonstrating that the synthetic pyrethroid deltamethrin 5 WP was very effective at reducing vector densities, no national VL vector control operations took place in Bangladesh between 1999 to early 2012. In 2012, IRS using deltamethrin 5 WP was re-introduced by the national programme, which consisted of pre-monsoon spraying in eight highly endemic sub-districts (upazilas). The present study aims to evaluate the effectiveness of IRS on VL vectors, as well as the process and performance of the spraying activities by national programme staff. METHODS: Five highly endemic upazilas of Mymensingh district were purposively selected (Fulbaria, Trishal, Mukthagacha, Gaforgaon and Bhaluka) to conduct the present study using the WHO/TDR monitoring and evaluation tool kit. IRS operations, conducted by 136 squads/teams, and 544 spraymen, were observed using check lists and questionnaires included in the WHO/TDR monitoring and evaluation tool kit. A household (HH) acceptability survey of IRS was conducted in all study areas using a structured questionnaire in 600 HHs. To measure the efficacy of IRS, pre-IRS (two weeks prior) and post-IRS (at one and five months after), vector density was measured using CDC light traps for two consecutive nights. Bioassays, using the WHO cone-method, were carried out in 80 HHs (40 sprayed and 40 unsprayed) to measure the effectiveness of the insecticide on sprayed surfaces. RESULTS: Of the 544 spraymen interviewed pre-IRS, 60%, 3% and 37% had received training for one, two and three days respectively. During spraying activities, 64% of the spraying squads had a supervisor in 4 upazilas but only one upazila (Mukthagacha) achieved 100% supervision of squads. Overall, 72.8% of the spraying squads in the study upazilas had informed HHs members to prepare their houses prior to spraying. The required personal protective equipment was not provided by the national programme during our observations and the spraying techniques used by all sprayers were sub-standard compared to the standard procedure mentioned in the M&E toolkit. In the HH interviews, 94.8% of the 600 respondents said that all their living rooms and cattle sheds had been sprayed. Regarding the effectiveness measurements (i.e. reduction of vector densities), a total of 4132 sand flies were trapped in three intervals, of which 3310 (80.1%) were P. argentipes; 46.5% (1540) males and 53.5% (1770) females. At one month post-IRS, P. argentipes densities were reduced by 22.5% but the 5 months post-IRS reduction was only 6.4% for both male and female. The bioassay tests showed a mean corrected mortality of P. argentipes sand flies at one month post-IRS of 87.3% which dropped to 74.5% at 4 months post-IRS in three upazilas, which is below the WHO threshold level (80%). CONCLUSION: The national programme should conduct monitoring and evaluation activities to ensure high quality of IRS operations as a pre-condition for achieving a fast and sustained reduction in vector densities. This will continue to be important during the maintenance phase of VL elimination on the Indian subcontinent. Further research is needed to determine other suitable vector control option(s) when the case numbers are very low.


Asunto(s)
Aerosoles/administración & dosificación , Control de Insectos/métodos , Insecticidas/administración & dosificación , Leishmaniasis Visceral/prevención & control , Psychodidae/crecimiento & desarrollo , Animales , Bangladesh , Bioensayo , Composición Familiar , Investigación sobre Servicios de Salud , Humanos , Nitrilos/administración & dosificación , Aceptación de la Atención de Salud , Densidad de Población , Psychodidae/efectos de los fármacos , Piretrinas/administración & dosificación , Encuestas y Cuestionarios , Análisis de Supervivencia
12.
Proc Natl Acad Sci U S A ; 115(29): E6920-E6926, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-29967151

RESUMEN

Isoxazolines are oral insecticidal drugs currently licensed for ectoparasite control in companion animals. Here we propose their use in humans for the reduction of vector-borne disease incidence. Fluralaner and afoxolaner rapidly killed Anopheles, Aedes, and Culex mosquitoes and Phlebotomus sand flies after feeding on a drug-supplemented blood meal, with IC50 values ranging from 33 to 575 nM, and were fully active against strains with preexisting resistance to common insecticides. Based on allometric scaling of preclinical pharmacokinetics data, we predict that a single human median dose of 260 mg (IQR, 177-407 mg) for afoxolaner, or 410 mg (IQR, 278-648 mg) for fluralaner, could provide an insecticidal effect lasting 50-90 days against mosquitoes and Phlebotomus sand flies. Computational modeling showed that seasonal mass drug administration of such a single dose to a fraction of a regional population would dramatically reduce clinical cases of Zika and malaria in endemic settings. Isoxazolines therefore represent a promising new component of drug-based vector control.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Culicidae/crecimiento & desarrollo , Insecticidas/farmacología , Control de Mosquitos/métodos , Mosquitos Vectores/crecimiento & desarrollo , Psychodidae/crecimiento & desarrollo , Animales , Humanos
13.
PLOS Neglected Tropical Diseases ; 12(4): 1-14, Abr, 2018. ilus, tab, graf
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-SUCENPROD, Sec. Est. Saúde SP | ID: biblio-1065047

RESUMEN

Zoonotic Visceral leishmaniasis (ZVL) is a neglected tropical disease that in the Americas iscaused by the infection of Leishmania infantum and the domestic dog (Canis familiaris) isthe main parasite reservoir in urban areas. The parasite is mainly transmitted by populationsof the sibling species Lutzomyia longipalpis that has been spreading in countries including Brazil, Argentina, Paraguay and more recently Uruguay. Although bionomic parameters such as population survival and the duration of the gonotrophic cycle are critical in evaluating vector capacity, field studies have rarely been applied to sand fly populations. The present study sought to evaluate basic bionomic parameters related to the vectorial capacity ofthe (S)-9-methylgermacrene-B population of the Lu. longipalpis complex in a visceral leishmaniasis area of Sao Paulo state. The daily survival rate, the duration of the gonotrophic cycle and the dispersal pattern were evaluated through the mark- release-recapture method. A total of 1,547 males and 401 females were marked and released in five experiment scarried out between February 2013 and February 2014. The higher recapture rates occurred within 100 meters of the release point and the estimated daily survival rates varied between 0.69 and 0.89 for females and between 0.69 and 0.79 for males. The minimum duration of the gonotrophic cycle observed was five days. The absolute population size, calculate dranged from 900 to 4,857 females and from 2,882 to 9,543 males. Our results demonstrate a high survival rate of this vector population and low dispersal that could be associated with the presence of all necessary conditions for its establishment and maintenancein the peridomiciles of this area. Our findings contribute to the basic data necessary for the understanding of ZVL dynamics and the evaluation of the implementation of prevention and control measures...


Asunto(s)
Animales , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/transmisión , Psychodidae/crecimiento & desarrollo , Psychodidae/genética
14.
Parasit Vectors ; 11(1): 155, 2018 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-29514680

RESUMEN

BACKGROUND: Leishmaniasis represents an important public health problem in Brazil. The continuous process of urbanization and expansion of human activities in forest areas impacts natural habitats, modifying the ecology of some species of Leishmania, as well as its vectors and reservoirs and, consequently, changes the epidemiological pattern that contributes to the expansion of American cutaneous leishmaniasis in Brazil. Here, we discuss Lutzomyia (Nyssomyia) whitmani, the main vector of ACL, transmitting two dermotropic Leishmania species including Leishmania (Viannia) braziliensis and Leishmania (V.) shawi. METHODS: We used the maximum entropy niche modelling approach (MaxEnt) to evaluate the environmental suitability of L. (N.) whitmani and the transmission of ACL in Brazil, in addition to designing models for a future scenario of climate change. MaxEnt was used under the "auto-features" mode and the default settings, with 100-fold repetition (bootstrap). The logistic output was used with higher values in the habitat suitability map, representing more favourable conditions for the occurrence of L. (N.) whitmani and human cases of ACL. RESULTS: Two models were developed: the Lutzomyia (N.) whitmani model (LWM) and the American cutaneous leishmaniasis model (ACLM). LWM identified the species "preferential habitat" included regions with moderate annual precipitation (AP) between 1000-1600 mm, intermediate vegetation density (NDVI) values, mean temperature of the coldest quarter (MTCQ), between 15-21 °C, and annual mean temperature (AMT), between 19-24 °C. ACLM indicates that ACL is strongly associated with areas of intermediate density vegetation, areas with AP between 800-1200 mm, MTCQ above 16 °C and AMT below 23 °C. CONCLUSIONS: The models generated for L. (N.) whitmani and ACL indicated a satisfactory predictive capacity. Future projections of LWM indicate an expansion of climatic suitability for L. (N.) whitmani for the northern and southern regions of Brazil. Future projections of ACL indicate the ongoing process of disease expansion in the face of the predicted climatic changes and reinforce the broad geographical expanse of this disease in Brazil. The models were able to identify that a continuous process of environmental degradation favours the establishment of L. (N.) whitmani and the occurrence of ACL by a strong association of the vector(s) and ACL to areas of intermediate vegetation cover density.


Asunto(s)
Insectos Vectores/crecimiento & desarrollo , Leishmania/aislamiento & purificación , Leishmaniasis Cutánea/epidemiología , Psychodidae/crecimiento & desarrollo , Animales , Brasil/epidemiología , Cambio Climático , Exposición a Riesgos Ambientales , Humanos , Insectos Vectores/parasitología , Modelos Estadísticos , Psychodidae/parasitología , Temperatura
15.
Bull Soc Pathol Exot ; 111(5): 309-315, 2018.
Artículo en Francés | MEDLINE | ID: mdl-30950594

RESUMEN

Phlebotomine sandflies are bloodsucking insects responsible for the transmission of leishmaniasis. The average annual incidence in Morocco, of this pathology, was approximately estimated in 2014 as 7.8 per 100.000 inhabitants according to the Moroccan health information service records. The study of the composition of the Phlebotomian community and its seasonal dynamics are essential for determining the appropriate and adequate means of control at the prefecture of Meknes in Central Morocco. It is with this in mind that two capture sessions per month using sticky paper traps were conducted at the sites of sandflies. A total of 982 sandflies were captured. The identification of the specimens found via the Moroccan key revealed a percentage of 73.3% belonging to the subgenus Paraphlebotomus, 6.3% to the Phlebotomus subgenus, 16.2% to Larroussius, and 4.2% of Sergentomia subgenus. Phlebotomus sergenti, vector of human cutaneous leishmaniasis, was found as the more abundant with 73.3% followed by Larroussius longicuspis with 8.2%. The largest number of species was harvested in July and September with, respectively, 44.8 ph/m2/night and 48.7 ph/m2/night. This study also unveiled that the two high-risk Leishmanian months are July and September, hence, the need to strengthen efforts to monitor and control this disease during the vector activity period.


Les phlébotomes sont des insectes hématophages vecteurs de la leishmaniose. L'incidence moyenne annuelle de cette affection au Maroc a été approximativement estimée en 2014 à 7,8 pour 100 000 habitants selon les registres du service de l'information sanitaire marocaine. L'étude de la composition du peuplement phlébotomienne et celle de la dynamique saisonnière des espèces locales sont indispensables pour déterminer les moyens de lutte contre cette pathologie. Dans cette optique, deux séances de capture par mois en utilisant des pièges adhésifs ont été effectuées pour déterminer les espèces phlébotomiennes et leurs fluctuations saisonnières dans la préfecture de Meknès au centre du Maroc. Neuf cent quatre-vingt-deux phlébotomes ont été identifiés, dont 73,3 % du sous-genre, Paraphlebotomus, 6,3 % du sous-genre Phlebotomus, 16,2 % du sous-genre Larroussius et 4,2 % du sous-genre de Sergentomia. Phlebotomus sergenti, vecteur de la leishmaniose cutanée humaine, est le plus abondant avec 73,3 % suivi par Larroussius longicuspis avec 8,2 %. Le maximum d'espèces a été récolté aux mois de juillet et septembre avec respectivement 44,8 et 45,8 phlébotomes/m2 par nuit (ph/m2 par nuit). Cette étude montre que les deux mois à haut risque leishmanien se situent en juillet et septembre, d'où la nécessité de renforcer les efforts de lutte contre cette maladie durant ces périodes.


Asunto(s)
Leishmaniasis Cutánea/epidemiología , Phlebotomus , Animales , Mordeduras y Picaduras/epidemiología , Humanos , Insectos Vectores/crecimiento & desarrollo , Marruecos/epidemiología , Phlebotomus/crecimiento & desarrollo , Dinámica Poblacional , Vigilancia de la Población , Psychodidae/clasificación , Psychodidae/crecimiento & desarrollo , Sistema de Registros , Estaciones del Año
16.
Insect Biochem Mol Biol ; 93: 47-56, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29248738

RESUMEN

The aim of the study was to evaluate the potential of matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) for the species identification of sand flies at different developmental stages and map changes in their protein profiles during the course of whole life cycle. Specimens of six different species from laboratory colonies at larval and pupal stages were examined using MALDI-TOF MS. The protein profiles of larvae were stable from the L2 to L4 developmental stages and clearly distinguishable at the species level. In a validation study, 123 larvae of the six species were queried against reference database resulting in 93% correct species identification (log score values higher than 2.0). The spectra generated from sand fly pupae allow species identification as well and surprisingly, in contrast to biting midges and mosquitoes, they did not change during this developmental stage. For adults, thorax was revealed as the optimal body part for sample preparation yielding reproducible spectra regardless age and diet. Only variations were uncovered for freshly engorged females profiles of which were affected by blood signals first two days post bloodmeal. The findings demonstrate that in addition to adult species differentiation MALDI-TOF MS may also serve as a rapid and effective tool for species identification of juvenile stages of phlebotomine sand flies.


Asunto(s)
Psychodidae/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Femenino , Larva/clasificación , Larva/crecimiento & desarrollo , Psychodidae/crecimiento & desarrollo , Pupa/clasificación , Pupa/crecimiento & desarrollo , Especificidad de la Especie
17.
Bull Soc Pathol Exot ; 111(3): 148-151, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30793579

RESUMEN

This is the first record of a case of urinary myiasis in the Palestinian Territories caused by Clogmia albipunctata. Larvae were discharged through urine by a 28-year-old pregnant female whom complained of mild abdominal pain associated with burning sensation while urinating over the past 3 months. Detailed description of the larva was provided.


Il s'agit du premier cas de myiase urinaire dans les Territoires palestiniens due à Clogmia albipunctata. Les larves ont été excrétées dans les urines d'une patiente de 28 ans, enceinte, qui se plaignait de douleurs abdominales légères associées, les trois derniers mois, à une sensation de brûlure lors des mictions. Cet article présente également la description des larves.


Asunto(s)
Miasis/diagnóstico , Complicaciones Parasitarias del Embarazo/diagnóstico , Psychodidae , Infecciones Urinarias/diagnóstico , Dolor Abdominal/diagnóstico , Dolor Abdominal/parasitología , Adulto , Animales , Árabes , Femenino , Humanos , Larva , Miasis/orina , Embarazo , Psychodidae/crecimiento & desarrollo , Infecciones Urinarias/parasitología
18.
Acta Tropica ; 176(1): 455-462, Dez, 2017. map, tab, graf
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-SUCENPROD, Sec. Est. Saúde SP | ID: biblio-1059334

RESUMEN

Black fly and sandfly bites are related to the endemicity of pemphigus foliaceus (PF); however, an immune reaction against the salivary proteins from these flies still requires confirmation in the case of PF patients living in southeastern Brazil. Purpose: To georeference the distribution of Simuliidae (Diptera: Simuliidae) and Phlebotominae (Diptera: Psychodidae) and of PF cases in the northeastern region of São Paulo State, and to assess the humoral immune response against salivary gland extracts (SGEs) from biting flies in PF patients, relatives, and neighbours...


Asunto(s)
Humanos , Animales , Psychodidae/crecimiento & desarrollo , Psychodidae/genética , Pénfigo/clasificación , Pénfigo/diagnóstico , Simuliidae/crecimiento & desarrollo , Simuliidae/genética
19.
Parasite ; 24: 42, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29139377

RESUMEN

Laboratory colonies of phlebotomine sand flies are necessary for experimental study of their biology, behaviour and mutual relations with disease agents and for testing new methods of vector control. They are indispensable in genetic studies and controlled observations on the physiology and behaviour of sand flies, neglected subjects of high priority. Colonies are of particular value for screening insecticides. Colonized sand flies are used as live vector models in a diverse array of research projects, including xenodiagnosis, that are directed toward control of leishmaniasis and other sand fly-associated diseases. Historically, labour-intensive maintenance and low productivity have limited their usefulness for research, especially for species that do not adapt well to laboratory conditions. However, with growing interest in leishmaniasis research, rearing techniques have been developed and refined, and sand fly colonies have become more common, enabling many significant breakthroughs. Today, there are at least 90 colonies representing 21 distinct phlebotomine sand fly species in 35 laboratories in 18 countries worldwide. The materials and methods used by various sand fly workers differ, dictated by the availability of resources, cost or manpower constraints rather than choice. This paper is not intended as a comprehensive review but rather a discussion of methods and techniques most commonly used by researchers to initiate, establish and maintain sand fly colonies, with emphasis on the methods proven to be most effective for the species the authors have colonized. Topics discussed include collecting sand flies for colony stock, colony initiation, maintenance and mass-rearing procedures, and control of sand fly pathogens in colonies.


Asunto(s)
Insectos Vectores/crecimiento & desarrollo , Psychodidae/crecimiento & desarrollo , Animales , Pollos , Cricetinae , Femenino , Cobayas , Vivienda para Animales/clasificación , Vivienda para Animales/normas , India , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Insectos Vectores/fisiología , Masculino , Ratones , Oviposición , Psychodidae/clasificación , Psychodidae/parasitología , Psychodidae/fisiología , Conejos , Transportes/métodos
20.
Acta Trop ; 174: 102-105, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28705610

RESUMEN

The information in this protocol covers from the basic steps and material necessary to start a sand fly colony up to the specific details which are important to the success of a Nyssomyia neivai colony. The greatest problems in our colony of Ny. neivai were solved with specific care, for instance, using vermiculite and an adequate number of adults in oviposition containers; the control of fungus with the exact amount of diet for the larvae and humidity control; a second blood meal for females and control of the number of times animals are used for blood meals. Currently, our colony is at F22 generation.


Asunto(s)
Animales de Laboratorio/crecimiento & desarrollo , Cruzamiento/métodos , Larva/crecimiento & desarrollo , Psychodidae/crecimiento & desarrollo , Animales , Femenino
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