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1.
J Med Entomol ; 58(4): 1931-1935, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-33855452

RESUMEN

Sand fly larvae develop in sheltered humid habitats containing decaying organic matter on which they feed. Previously, we showed that gravid females of Phlebotomus papatasi Scopoli (Diptera: Psychodidae) are attracted to and stimulated to lay eggs on larval rearing medium containing larvae. That study, however, did not control for the possible effect of medium aging. Our goal in this study was to evaluate the effect of larval substrate conditioning on attraction and oviposition responses of Ph. papatasi sand flies while controlling for the effect of substrate aging. Initially, we confirmed that the pretreatment fresh larval food sources (to be used as larval conditioned and unconditioned media) did not differ with respect to their effect on attraction and oviposition responses. The larval conditioned medium was produced by rearing larvae to the second/third-instar stage over 3 wk using the same larval food source. To produce larval unconditioned medium, the same amount of fresh larval food was added to a control rearing cup that did not contain larvae but was aged under identical time and conditions. Two-choice bioassays were conducted to evaluate gravid female's attraction and oviposition response to larval conditioned and unconditioned media. We found that gravid females were significantly attracted (P < 0.05) to larval conditioned medium when compared with unconditioned medium under the same amount of time and conditions. However, no such difference was found with respect to oviposition response. Both attraction and oviposition responses were significantly increased for larval conditioned and unconditioned media in comparison to the initial fresh larval food source.


Asunto(s)
Alimentación Animal , Phlebotomus/crecimiento & desarrollo , Animales , Bioensayo , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/fisiología , Oviposición , Phlebotomus/fisiología
2.
J Med Entomol ; 57(4): 1301-1304, 2020 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-31953543

RESUMEN

Maintenance of laboratory colonies of insects and other arthropod pests offers significant research advantages. The availability, age, sex, housing conditions, nutrition, and relative uniformity over time of biological material for research facilitate comparison of results between experiments that would otherwise be difficult or impossible. A laboratory research colony of Phlebotomus papatasi (Scopoli), old world sand flies, was maintained with high-colony productivity for a number of years, but within a relatively short (4-6 mo) time period, colony productivity declined from over 10,000 flies per week to less than 100 per week. Mites and nematodes were both visible in the larval medium; however, the mites had been present throughout high productivity periods; therefore, it seemed reasonable to investigate the nematodes. PCR amplification of 18S rRNA yielded a clean cDNA sequence identified by BLAST search as Procephalobus sp. 1 WB-2008 (Rhabditida: Panagrolaimidae) small subunit ribosomal RNA gene, GenBank EU543179.1, with 475/477 nucleotide identities. Nematode samples were collected and identified as Tricephalobus steineri, (Andrássy, 1952) Rühm, 1956 (Rhabditida: Panagrolaimidae) based on morphological characteristics of the esophagus and the male copulatory apparatus. Mites (Tyrophagus putrescentiae [Acariformes: Acaridae]) may have played an additional predatory role in the loss of sand fly colony productivity. We hypothesized that the origin of the nematode infestation was rabbit dung from a local rabbitry used in preparation of the larval medium. Colony productivity was fully restored within 3 mo (two sand fly generational periods) by replacement of the rabbit dung from a clean source for use to prepare sand fly larval medium.


Asunto(s)
Interacciones Huésped-Parásitos , Phlebotomus/fisiología , Phlebotomus/parasitología , Rabdítidos/fisiología , Animales , Femenino , Larva/crecimiento & desarrollo , Larva/parasitología , Larva/fisiología , Masculino , Phlebotomus/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa , Dinámica Poblacional , ARN de Helminto/análisis , ARN Ribosómico 18S/análisis
3.
J Med Entomol ; 57(3): 852-861, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-31813978

RESUMEN

Most sand flies and mosquitoes require a bloodmeal for egg production, but when blood-sources are scarce, some of them can reproduce without it, so called facultative autogeny. The evolution of autogenous reproduction is thought to involve a trade-off between the benefit of reproducing in the absence of bloodmeal hosts versus the quantitative cost of reduced fecundity and/or or qualitative effect on reduced offspring development and survivorship. We blood-fed (BF) some Phlebotomous papatasi (Scopoli) sand fly females on mice while keeping others (from the same cohort) not BF. We then compared the fecundity of BF and non-blood-fed (NBF) females and also evaluated their egg mass and hatching rate, larval development rate and survivorship, pupa mass and eclosion rates, and progeny fecundity. Among NBF females, only 55% became gravid and produced three times less mature oocytes than BF ones. Autogenous females laid 3.5 and 5.7 times fewer eggs in individual and multi-female bioassays, respectively. Egg mass and hatching rate were not affected by blood-feeding. Individual-larvae bioassays suggested reduced survival during larval stages in the autogenous group. In multi-larvae bioassays, overall and especially pupae survival was significantly reduced in the autogenous group. Development rate was slower and pupal mass was reduced in progeny from autogenous mothers. These effects were particularly apparent at high larval density. Mothers' blood-feeding history did not affect daughter's fecundity. Studies on the costs of autogeny provides insights on the evolution of blood feeding. Moreover, it also provides insights regarding potential implications of autogeny to the emergence of vector-borne diseases.


Asunto(s)
Longevidad , Phlebotomus/fisiología , Animales , Conducta Alimentaria , Femenino , Fertilidad , Larva/crecimiento & desarrollo , Larva/fisiología , Masculino , Ratones , Ratones Endogámicos ICR , Phlebotomus/crecimiento & desarrollo , Pupa/crecimiento & desarrollo , Reproducción
4.
Methods Mol Biol ; 1971: 351-368, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30980314

RESUMEN

Sand fly colonies are of major importance for experimental studies on biology, behavior, vector competence, relationship with Leishmania parasites, and vector control. This chapter is intended to provide methods and techniques used to initiate, establish, and maintain sand fly colonies. Details on collecting sand flies for colonization, colony initiation, maintenance, and experimental infection of Phlebotomus spp. with Leishmania spp. are reported.


Asunto(s)
Insectos Vectores , Leishmania/crecimiento & desarrollo , Phlebotomus , Animales , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/parasitología , Phlebotomus/crecimiento & desarrollo , Phlebotomus/parasitología
5.
Parasitol Res ; 118(5): 1371-1384, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30911912

RESUMEN

Sand flies were collected in a location from Romania in order to estimate their abundance and seasonal variation in correlation with environmental and anthropic factors. From May to October 2017, eight premises with different animal species were sampled for sand flies in a household from Fundatura village, Vaslui County, in North-Eastern Romania. Animal-related data, shelter-related data, and climatic parameters were recorded. All (n = 150) collected sand flies were Phlebotomus perfiliewi. A mono-modal type of abundance trend has been recorded (a single peak at the beginning of August). The first day of capture was in mid-July. The total number of females during the peak season was significantly higher than the total number of males. The highest percentage of males was recorded at the beginning and at the end of the sand fly activity. Only the traps placed in the poultry enclosure built from clay and wood were positive. A strong positive correlation was recorded between the total number of collected sand flies and the minimum and the maximum temperature. The analysis of the climatic data shows that the first presence of sand flies was registered only after the average minimum temperature for the previous 7 days was above 15 °C.


Asunto(s)
Animales Domésticos/parasitología , Insectos Vectores/parasitología , Leishmaniasis Visceral/epidemiología , Phlebotomus/parasitología , Aves de Corral/parasitología , Estaciones del Año , Animales , Clima , Ambiente , Femenino , Leishmania infantum/crecimiento & desarrollo , Leishmania infantum/aislamiento & purificación , Masculino , Phlebotomus/crecimiento & desarrollo , Dinámica Poblacional , Rumanía/epidemiología , Temperatura
6.
Parasit Vectors ; 11(1): 214, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29587873

RESUMEN

BACKGROUND: Phlebotomus papatasi sand flies are major vectors of Leishmania major and phlebovirus infection in North Africa and across the Middle East to the Indian subcontinent. Population genetics is a valuable tool in understanding the level of genetic variability present in vector populations, vector competence, and the development of novel control strategies. This study investigated the genetic differentiation between P. papatasi populations in Egypt and Jordan that inhabit distinct ecotopes and compared this structure to P. papatasi populations from a broader geographical range. METHODS: A 461 base pair (bp) fragment from the mtDNA cytochrome b (cyt b) gene was PCR amplified and sequenced from 116 individual female sand flies from Aswan and North Sinai, Egypt, as well as Swaimeh and Malka, Jordan. Haplotypes were identified and used to generate a median-joining network, F ST values and isolation-by-distance were also evaluated. Additional sand fly individuals from Afghanistan, Iran, Israel, Jordan, Libya, Tunisia and Turkey were included as well as previously published haplotypes to provide a geographically broad genetic variation analysis. RESULTS: Thirteen haplotypes displaying nine variant sites were identified from P. papatasi collected in Egypt and Jordan. No private haplotypes were identified from samples in North Sinai, Egypt, two were observed in Aswan, Egypt, four from Swaimeh, Jordan and two in Malka, Jordan. The Jordan populations clustered separately from the Egypt populations and produced more private haplotypes than those from Egypt. Pairwise F ST values fall in the range 0.024-0.648. CONCLUSION: The clustering patterns and pairwise F ST values indicate a strong differentiation between Egyptian and Jordanian populations, although this population structure is not due to isolation-by-distance. Other factors, such as environmental influences and the genetic variability in the circulating Le. major parasites, could possibly contribute to this heterogeneity. The present study aligns with previous reports in that pockets of genetic differentiation exists between populations of this widely dispersed species but, overall, the species remains relatively homogeneous.


Asunto(s)
Citocromos b/genética , Variación Genética , Genética de Población , Haplotipos , Phlebotomus/clasificación , Phlebotomus/crecimiento & desarrollo , Filogeografía , Animales , Egipto , Insectos Vectores/clasificación , Insectos Vectores/genética , Insectos Vectores/crecimiento & desarrollo , Jordania , Phlebotomus/genética
7.
Parasit Vectors ; 11(1): 160, 2018 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-29523212

RESUMEN

BACKGROUND: Phlebotomus papatasi is a widely distributed sand fly species in different tropical and sub-tropical regions including the Middle East and North Africa. It is considered an important vector that transmits Leishmania major parasites, the causative agents of cutaneous leishmaniasis. The development of microsatellite markers for this sand fly vector is of high interest to understand its population structure and to monitor its geographic dispersal. RESULTS: Fourteen polymorphic microsatellite markers were developed with simple di-, tri- and tetra-nucleotide repeats. The F statistics calculated for the 14 markers revealed high genetic diversity; expected heterozygosity (He) ranged from 0.407 to 0.767, while observed heterozygosity (Ho) was lower and ranged from 0.083 to 0.514. The number of alleles sampled fall in the range of 9-29. Three out of 14 markers deviated from Hardy-Weinberg expectations, no significant linkage disequilibrium was detected and high values for inbreeding coefficient (FIS) were likely due to inbreeding. CONCLUSIONS: The development of these functional microsatellites enable a high resolution of P. papatasi populations. It opens a path for researchers to perform multi locus-based population genetic structure analyses, and comparative mapping, a part of the efforts to uncover the population dynamics of this vector, which is an important global strategy for understanding the epidemiology and control of leishmaniasis.


Asunto(s)
Distribución Animal , Etiquetas de Secuencia Expresada , Insectos Vectores/clasificación , Insectos Vectores/crecimiento & desarrollo , Repeticiones de Microsatélite , Phlebotomus/clasificación , Phlebotomus/crecimiento & desarrollo , África del Norte , Alelos , Animales , Variación Genética , Genotipo , Heterocigoto , Insectos Vectores/genética , Medio Oriente , Phlebotomus/genética
8.
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
9.
J Vector Borne Dis ; 54(3): 233-239, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29097638

RESUMEN

BACKGROUND & OBJECTIVES: Cutaneous leishmaniasis displays two epidemiological routes of transmission, zoonotic cutaneous leishmaniasis (ZCL) which includes animal reservoir hosts in the transmission cycle and anthroponotic cutaneous leishmaniasis (ACL), where human is the sole source of infection for the vector sandflies. About 10-13% of CL cases are reported each year from Adana province in Turkey. The aim of this study was to develop a predictive model for determining the spatial risk level of cutaneous leishmaniasis in the Adana province, southern part of Turkey, in relation to environmental factors. METHODS: Entomological survey was carried out between June 2015 and September 2016. Sandflies were collected from Karaisali district of the Adana province using light-traps and sticky papers. Sandfly fauna results were compared with environmental data obtained from field-survey, and examined with univariate and binary logistic regression in PASW statistical software. The ArcMap application of ArcGIS10.0. software was used for geographical adjustments to create maps and establish a risk model. RESULTS: In total five sandfly species were identified in the study area, and three of them (Phlebotomus tobbi, P. neglectus/syriacus and P. perfiliewi) were detected as potential vectors of cutaneous leishmaniasis. The results showed that enhanced vegetation index (EVI) and emissivity band 31 (EMIS31) values are related to the distribution of these three species. INTERPRETATION & CONCLUSION: The created risk maps may provide useful information to guide the control programme interventions and prevent the economic loses in the future insecticide applications. They could be used to better understand the distribution of vectors, and determine the epidemiology and risk level of the CL.


Asunto(s)
Demografía , Insectos Vectores/crecimiento & desarrollo , Leishmaniasis Cutánea/epidemiología , Phlebotomus/crecimiento & desarrollo , Animales , Sistemas de Información Geográfica , Factores de Riesgo , Topografía Médica , Turquía/epidemiología
10.
PLoS Negl Trop Dis ; 11(9): e0005890, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28873425

RESUMEN

BACKGROUND: A number of studies on visceral leishmaniasis (VL) vector control have been conducted during the past decade, sometimes came to very different conclusion. The present study on a large sample investigated different options which are partially unexplored including: (1) indoor residual spraying (IRS) with alpha cypermethrin 5WP; (2) long lasting insecticide impregnated bed-net (LLIN); (3) impregnation of local bed-nets with slow release insecticide K-O TAB 1-2-3 (KOTAB); (4) insecticide spraying in potential breeding sites outside of house using chlorpyrifos 20EC (OUT) and different combinations of the above. METHODS: The study was a cluster randomized controlled trial where 3089 houses from 11 villages were divided into 10 sections, each section with 6 clusters and each cluster having approximately 50 houses. Based on vector density (males plus females) during baseline survey, the 60 clusters were categorized into 3 groups: (1) high, (2) medium and (3) low. Each group had 20 clusters. From these three groups, 6 clusters (about 300 households) were randomly selected for each type of intervention and control arms. Vector density was measured before and 2, 4, 5, 7, 11, 14, 15, 18 and 22 months after intervention using CDC light traps. The impact of interventions was measured by using the difference-in-differences regression model. RESULTS: A total of 17,434 sand flies were collected at baseline and during the surveys conducted over 9 months following the baseline measurements. At baseline, the average P. argentipes density per household was 10.6 (SD = 11.5) in the control arm and 7.3 (SD = 8.46) to 11.5 (SD = 20.2) in intervention arms. The intervention results presented as the range of percent reductions of sand flies (males plus females) and rate ratios in 9 measurements over 22 months. Among single type interventions, the effect of IRS with 2 rounds of spraying (applied by the research team) ranged from 13% to 75% reduction of P. argentipes density compared to the control arm (rate-ratio [RR] ranged from 0.25 to 0.87). LLINs caused a vector reduction of 9% to 78% (RR, 0.22 to 0.91). KOTAB reduced vectors by 4% to 73% (RR, 0.27 to 0.96). The combination of LLIN and OUT led to a vector reduction of 26% to 86% (RR, 0.14 to 0.74). The reduction for the combination of IRS and OUT was 8% to 88% (RR, 0.12 to 0.92). IRS and LLIN combined resulted in a vector reduction of 13% to 85% (RR, 0.15 to 0.77). The IRS and KOTAB combination reduced vector densities by 16% to 86% (RR, 0.14 to 0.84). Some intermediate measurements for KOTAB alone and for IRS plus LLIN; and IRS plus KOTAB were not statistically significant. The bioassays on sprayed surfaces or netting materials showed favourable results (>80% mortality) for 22 months (IRS tested for 12 months). In the KOTAB, a gradual decline was observed after 6 months. CONCLUSIONS: LLIN and OUT was the best combination to reduce VL vector densities for 22 months or longer. Operationally, this is much easier to apply than IRS. A cost analysis of the preferred tools will follow. The relationship between vector density (males plus females) and leishmaniasis incidence should be investigated, and this will require estimates of the Entomological Inoculation Rate.


Asunto(s)
Control de Insectos/métodos , Insectos Vectores/crecimiento & desarrollo , Phlebotomus/crecimiento & desarrollo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Bangladesh , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Densidad de Población , Adulto Joven
11.
Parasit Vectors ; 9(1): 578, 2016 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-27842606

RESUMEN

BACKGROUND: Phlebotomus ariasi Tonnoir, 1921, is the predominant sand fly species in the Cevennes region and a proven vector of Leishmania infantum, which is the main pathogen of visceral and canine leishmaniasis in the south of France. Even if this species is widely present in Western Mediterranean countries, its biology and ecology remain poorly known. The main goals of this work are to investigate the phenotypic variation of P. ariasi at a local scale in a region characterized by climatic and environmental fluctuations, and to determine if slope and altitude could affect the sand fly phenotypes. RESULTS: Sand flies were captured along a 14 km-long transect in 2011 from May to October. At the same time, environmental data such as altitude and slope were also collected. Morphological analysis of P. ariasi wings was performed by a geometric morphometrics approach. We found morphological variation among local populations of P. ariasi. Strong shape and size variations were observed in the course of the season (particularly in June and July) for both genders. During June, we highlighted differences in wing phenotypes according to altitude for both sexes and to slope and station for females. CONCLUSIONS: The phenotypic variations observed in P. ariasi along the studied transect indicated these populations are subjected to environmental pressures. Nevertheless, it seems that sand flies are more sensitive to extrinsic factors in June and July, suggesting a phenotypic plasticity.


Asunto(s)
Insectos Vectores/anatomía & histología , Insectos Vectores/crecimiento & desarrollo , Phlebotomus/anatomía & histología , Phlebotomus/crecimiento & desarrollo , Alas de Animales/anatomía & histología , Animales , Biometría , Francia , Insectos Vectores/clasificación , Phlebotomus/clasificación , Filogeografía
12.
PLoS One ; 11(10): e0165155, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27783667

RESUMEN

The monthly distribution and abundance of sand flies are influenced by both biotic and abiotic factors. The present study aimed to evaluate the seasonal distribution of sand flies and the relation between their abundance and environmental parameters, including vegetation and climate. This study was conducted over a 2-year period (April 2012 to March 2014). Monthly distribution was evaluated through the weekly deployment of CDC light traps in the peridomicile area of 5 residences in an urban area of the municipality of Corumbá in the State of Mato Grosso do Sul, Brazil. Meteorological data were obtained from the Mato Grosso do Sul Center for Weather, Climate, and Water Resources. The spectral indices were calculated based on spatial resolution images (GeoEye) and the percentage of vegetal coverage. Differences in the abundance of sand flies among the collection sites were assessed using the Kruskal-Wallis test, and the strength of correlations between environmental variables was determined by calculating Spearman's correlation coefficients. Lutzomyia cruzi, Lu. forattinii, and Evandromyia corumbaensis were the most frequently found species. Although no significant association was found among these sand fly species and the tested environmental variables (vegetation and climate), high population peaks were found during the rainy season, whereas low peaks were observed in the dry season. The monthly distribution of sand flies was primarily determined by Lu. cruzi, which accounted for 93.94% of the specimens collected each month throughout the experimental period. The fact that sand flies were detected year-round indicates a continuous risk of infection to humans, demonstrating the need for targeted management and education programs.


Asunto(s)
Leishmaniasis Visceral/epidemiología , Phlebotomus/crecimiento & desarrollo , Animales , Brasil/epidemiología , Epidemias , Humanos , Humedad , Insectos Vectores/parasitología , Leishmaniasis Visceral/parasitología , Phlebotomus/fisiología , Densidad de Población , Estaciones del Año , Temperatura
13.
Parasit Vectors ; 9(1): 553, 2016 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-27756429

RESUMEN

BACKGROUND: In mosquitoes, it has previously been shown that rearing conditions of immature stages have an effect on the vector competence of adults. Here, we studied the impact of different larval rearing temperatures (27 °C versus 32 °C) on the sand fly Phlebotomus sergenti Parrot, 1917 and its susceptibility to two parasites: Leishmania tropica Wright, 1903, a dixenous trypanosomatid transmissible from sand flies to humans, and Psychodiella sergenti Lantova, Volf & Votypka, 2010, a monoxenous sand fly gregarine. RESULTS: Increased rearing temperature (32 °C) affected the larval developmental times and size of P. sergenti adults but had no effect on the susceptibility of P. sergenti to L. tropica. No differences were found in Leishmania infection rates or in the intensities of Leishmania infection. Interestingly, increased larval rearing temperature significantly suppressed the development of gregarines. All 117 control sand flies tested were infected with Ps. sergenti, and the mean number of gamonts per individual was 29.5. In contrast, only three of 120 sand flies maintained at 32 °C were infected and the mean number of gamonts per individual was just 0.04. CONCLUSIONS: We demonstrated that the increased rearing temperature of P. sergenti larvae had no impact on the development of L. tropica in adult sand flies but had a profound effect on the gregarine Ps. sergenti. We suggest that increasing the larval rearing temperature by 5 °C is a simple and effective way to clean sand fly colonies infected by gregarines.


Asunto(s)
Apicomplexa/fisiología , Leishmania tropica/fisiología , Phlebotomus/crecimiento & desarrollo , Phlebotomus/parasitología , Animales , Femenino , Interacciones Huésped-Parásitos , Control de Insectos , Insectos Vectores/parasitología , Larva/fisiología , Temperatura
14.
PLoS Negl Trop Dis ; 10(8): e0004868, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27537774

RESUMEN

BACKGROUND: Visceral leishmaniasis (VL) is a disease caused by two known vector-borne parasite species (Leishmania donovani, L. infantum), transmitted to man by phlebotomine sand flies (species: Phlebotomus and Lutzomyia), resulting in ≈50,000 human fatalities annually, ≈67% occurring on the Indian subcontinent. Indoor residual spraying is the current method of sand fly control in India, but alternative means of vector control, such as the treatment of livestock with systemic insecticide-based drugs, are being evaluated. We describe an individual-based, stochastic, life-stage-structured model that represents a sand fly vector population within a village in India and simulates the effects of vector control via fipronil-based drugs orally administered to cattle, which target both blood-feeding adults and larvae that feed on host feces. PRINCIPLE FINDINGS: Simulation results indicated efficacy of fipronil-based control schemes in reducing sand fly abundance depended on timing of drug applications relative to seasonality of the sand fly life cycle. Taking into account cost-effectiveness and logistical feasibility, two of the most efficacious treatment schemes reduced population peaks occurring from April through August by ≈90% (applications 3 times per year at 2-month intervals initiated in March) and >95% (applications 6 times per year at 2-month intervals initiated in January) relative to no control, with the cumulative number of sand fly days occurring April-August reduced by ≈83% and ≈97%, respectively, and more specifically during the summer months of peak human exposure (June-August) by ≈85% and ≈97%, respectively. CONCLUSIONS: Our model should prove useful in a priori evaluation of the efficacy of fipronil-based drugs in controlling leishmaniasis on the Indian subcontinent and beyond.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Insectos Vectores , Insecticidas/administración & dosificación , Leishmaniasis Visceral/prevención & control , Leishmaniasis/prevención & control , Phlebotomus , Pirazoles/administración & dosificación , Adulto , Animales , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/prevención & control , Control de Enfermedades Transmisibles/economía , Control de Enfermedades Transmisibles/estadística & datos numéricos , Simulación por Computador , Humanos , India/epidemiología , Insectos Vectores/efectos de los fármacos , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/parasitología , Leishmania donovani/efectos de los fármacos , Leishmaniasis/tratamiento farmacológico , Leishmaniasis/veterinaria , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/parasitología , Masculino , Modelos Estadísticos , Phlebotomus/efectos de los fármacos , Phlebotomus/crecimiento & desarrollo , Phlebotomus/parasitología , Pirazoles/uso terapéutico
15.
Zootaxa ; 4105(5): 455-82, 2016 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-27394791

RESUMEN

The egg exochorion, larval instars and pupa of the phlebotomine sand fly Micropygomyia (Coquillettimyia) chiapanensis (Dampf) are described and illustrated based on specimens collected in the locality of Farallón, municipality of Actopan, Veracruz, Mexico. Morphology of fourth instar larval mouthparts, particularly the incisor lobe and molar lobe shape of mandible, could be important for species identification of immature Phlebotominae. In this work is compared the pupal chaetotaxy of Mi. chiapanensis with other species previously described. The fourth instar larva of Mi. chiapanensis is compared with other species of this genus, the most important differentiating characters being the size, shape and position of the abdominal dorsal internal seta.


Asunto(s)
Larva/crecimiento & desarrollo , Phlebotomus/crecimiento & desarrollo , Pupa/crecimiento & desarrollo , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Femenino , Larva/anatomía & histología , Larva/clasificación , Masculino , México , Tamaño de los Órganos , Phlebotomus/anatomía & histología , Phlebotomus/clasificación , Pupa/anatomía & histología , Pupa/clasificación
16.
PLoS Negl Trop Dis ; 10(2): e0004381, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26863317

RESUMEN

Cutaneous leishmaniasis ranks among the tropical diseases least known and most neglected in Libya. World Health Organization reports recognized associations of Phlebotomus papatasi, Psammomys obesus, and Meriones spp., with transmission of zoonotic cutaneous leishmaniasis (ZCL; caused by Leishmania major) across Libya. Here, we map risk of ZCL infection based on occurrence records of L. major, P. papatasi, and four potential animal reservoirs (Meriones libycus, Meriones shawi, Psammomys obesus, and Gerbillus gerbillus). Ecological niche models identified limited risk areas for ZCL across the northern coast of the country; most species associated with ZCL transmission were confined to this same region, but some had ranges extending to central Libya. All ENM predictions were significant based on partial ROC tests. As a further evaluation of L. major ENM predictions, we compared predictions with 98 additional independent records provided by the Libyan National Centre for Disease Control (NCDC); all of these records fell inside the belt predicted as suitable for ZCL. We tested ecological niche similarity among vector, parasite, and reservoir species and could not reject any null hypotheses of niche similarity. Finally, we tested among possible combinations of vector and reservoir that could predict all recent human ZCL cases reported by NCDC; only three combinations could anticipate the distribution of human cases across the country.


Asunto(s)
Gerbillinae/crecimiento & desarrollo , Leishmania major/aislamiento & purificación , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/transmisión , Phlebotomus/crecimiento & desarrollo , Zoonosis/epidemiología , Zoonosis/transmisión , Animales , Reservorios de Enfermedades , Ecosistema , Gerbillinae/parasitología , Humanos , Libia , Phlebotomus/parasitología , Filogeografía , Topografía Médica
17.
J Med Entomol ; 53(3): 533-540, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26839335

RESUMEN

The adult female of the sand fly species Martinsmyia minasensis (Mangabeira, 1942) is described, and the characters of the genus Martinsmyia Galati, 1995 are defined. We performed morphometric analyses on the spermatheca and wings, and present data on the geographical distribution of M. minasensis, as well as an identification key to females of this genus. The specimens were measured, drawn, photographed, and compared with the similar species M. oliveirai. It was possible to distinguish between M. minasensis and M. oliveirai based on differences found in the common and individual ducts of the spermatheca, as well as wing shape and size.


Asunto(s)
Phlebotomus/anatomía & histología , Phlebotomus/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Femenino , Masculino , Tamaño de los Órganos , Phlebotomus/genética , Phlebotomus/crecimiento & desarrollo , Filogenia , Alas de Animales/anatomía & histología , Alas de Animales/crecimiento & desarrollo
18.
Parasit Vectors ; 9: 60, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26830689

RESUMEN

BACKGROUND: Cutaneous Leishmaniasis (CL) is one of the most neglected tropical diseases in Morocco. Leishmania major and L. tropica are the main culprits identified in all endemic foci across the country. These two etiological agents are transmitted by Phlebotomus papatasi and P. sergenti, the two most prevalent sand fly species in Morocco. Previous studies reflected gaps of knowledge regarding the environmental fingerprints that affect the distribution of these two potential vectors across Morocco. METHODS: The sand flies were collected from 48 districts across Morocco using sticky paper traps. Collected specimens were preserved in 70% ethanol for further processing and identification. Male and female densities were calculated in each site to examine their relations to the environmental conditions across these sites. The study used 19 environmental variables including precipitation, aridity, elevation, soil variables and a composite representing maximum, minimum and mean of day- and night-time Land Surface Temperature (LST), and Normalized Difference Vegetation Index (NDVI). RESULTS: A total of 11,717 specimens were collected during this entomological survey. These specimens represented 11 species of two genera; Phlebotomus and Sergentomyia. Correlations of the sand fly densities with the environmental variables were estimated to identify the variables which influence the distribution of the two potential vectors, Phlebotomus papatasi and P. sergenti, associated with all CL endemic foci across the country. The density of P. papatasi was most affected by temperature changes. The study showed a significant positive correlation between the densities of both sexes of P. papatasi and night-time temperatures. Both P. papatasi and P. sergenti showed a negative correlation with aridity, but, such correlation was only significant in case of P. papatasi. NDVI showed a positive correlation only with densities of P. sergenti, while, soil PH and soil water stress were negatively correlated with the densities of both males and females of only P. papatasi. CONCLUSIONS: Our results identified the sand fly species across all CL endemic sites and underlined the influences of night-time temperature, soil water stress and NDVI as the most important variables affecting the sand fly distribution in all sampled sites. This preliminary study considered the importance of these covariates to anticipate the potential distribution of P. papatasi and P. sergenti in Morocco.


Asunto(s)
Enfermedades Endémicas , Leishmaniasis Cutánea/epidemiología , Phlebotomus/clasificación , Phlebotomus/crecimiento & desarrollo , Filogeografía , Psychodidae/clasificación , Psychodidae/crecimiento & desarrollo , Animales , Ecología , Femenino , Masculino , Marruecos/epidemiología
19.
J Med Entomol ; 53(3): 717-720, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26810730

RESUMEN

Phlebotomine sand flies from three counties in Liberia were collected from January 2011 to July 2013. In total, 3,118 sand flies were collected: 18 species were identified, 13 of which represented new records for Liberia. An updated taxonomic checklist is provided with a brief note on sand fly biology, and the disease vector potential for species is discussed.


Asunto(s)
Insectos Vectores/clasificación , Phlebotomus/clasificación , Animales , Tamaño Corporal , Lista de Verificación , Insectos Vectores/anatomía & histología , Insectos Vectores/crecimiento & desarrollo , Liberia , Phlebotomus/anatomía & histología , Phlebotomus/crecimiento & desarrollo , Estaciones del Año
20.
J Med Entomol ; 53(3): 712-716, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26768941

RESUMEN

Morphological variations were observed in specimens of the sand fly species Sergentomyia bailyi Sinton 1931 collected from Pondicherry Union Territory, India. Examination of morphological characteristics showed differences in the length of sensilla chaeticum on antennal flagellomere 3 (A3) in males and females, in the size and shape of the spermathecae in females, and in the position of accessory spines on the gonostyle of males. In our previous study, DNA barcoding characterization of this sand fly species collected from Pondicherry UT revealed molecular variations within the S. bailyi population. This study confirms the existence of a species complex within S. bailyi population at Pondicherry UT.


Asunto(s)
Phlebotomus/anatomía & histología , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , India , Masculino , Tamaño de los Órganos , Phlebotomus/genética , Phlebotomus/crecimiento & desarrollo
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