In vitro susceptibility to pentavalent antimony in Leishmania infantum strains is not modified during in vitro or in vivo passages but is modified after host treatment with meglumine antimoniate

BACKGROUND: Leishmaniasis is a common parasitic disease in Southern Europe, caused by Leishmania infantum. The failures of current treatment with pentavalent antimonials are partially attributable to the emergence of antimony-resistant Leishmania strains. This study analyses the in vitro susceptibility to pentavalent antimony of intracellular amastigotes from a range of L. infantum strains, derived from the same infected animal, during in vitro and in vivo passages and after host treatment with meglumine antimoniate. RESULTS: Sb(V)-IC50 values for strains from two distinct isolates from the same host and one stock after two years of culture in NNN medium and posterior passage to hamster were similar (5.0 ± 0.2; 4.9 ± 0.2 and 4.4 ± 0.1 mgSb(V)/L, respectively). In contrast, a significant difference (P < 0.01, t test) was observed between the mean Sb(V)-IC50 values in the stocks obtained before and after treatment of hosts with meglumine antimoniate (4.7 ± 0.4 mgSb(V)/L vs. 7.7 ± 1.5 mgSb(V)/L). Drug-resistance after drug pressure in experimentally infected dogs increased over repeated drug administration (6.4 ± 0.5 mgSb(V)/L after first treatment vs. 8.6 ± 1.4 mgSb(V)/L after the second) (P < 0.01, t test). CONCLUSIONS: These results confirm previous observations on strains from Leishmania/HIV co-infected patients and indicate the effect of the increasing use of antimony derivatives for treatment of canine leishmaniasis in endemic areas on the emergence of Leishmania antimony-resistant strains

Influencia de la edad en el parasitismo del ratón por el aspiculuris tetraptera y syphacia obvelata

Tesi de Llicenciatura per a la obtenció del Grau de Farmàcia. Facultat de Farmàcia. Universitat de Barcelona. Director: Jaime Gállego Berenguer. 1970

Agressivité du Simulium du complexe ornatum (Diptera, Simuliidae) en Catalogne (Espagne). Premiere mention

A l'heure actuelle, en Espagne, même si des Simulies sont incriminées chez l'homme, dans des lésions dues à des insectes hématophages, le lien direct entre ces piqûres et une espèce donnee de Simulie n'avait pas encore été éetabli pour ce pays. Une invasion récente (1993) de ces insectes dans la région de l'Alt Penedès, au nord-est de la province de Tarragone, permet aujourd'hui de combler cette lacune

Is leishmaniosis spreading to northern areas of the Iberian Peninsula? The examples of Lleida (NE Spain) and Andorra

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/46988The entomological and canine leishmaniosis surveys carried out in the northwest of Catalonia and in Andorra in the context of the European project Emerging Diseases in a changing European eNvironment (EDEN) are summarized. The aim of the study was to obtain data on the presence of leishmaniosis in these areas and the spatial distribution of their vectors

Is leishmaniasis endemic on the island of Minorca (Spain)?. A human visceral case after living 13 years in Minorca

Ecoepidemiologica studies performed in Minorca (Balearic Islands) seem to show that leishmaniasis is not endemic in this island, even in the presence of the vector. All cases of leishmaniasis in man or dog diagnosed in the island seem to come from other Spanish regions. A recent case of human visceral leishmaniasis in a man who had not left Minorca for 13 years calls into question this assumption or the time that Leishmania may persist asymptomatic in the host

First cases of gynandromorphism in Phlebotomus perniciosus Newstead, 1911 (Diptera, Psychodidae, Phlebotominae)

Two gynandromorphic specimens of Phlebotomus perniciosus Newstead, 1911 are described and illustrated for the first time The specimens were collected in the Northeast of the Iberian Peninsula (Spain)

El diagnóstico serológico de la leishmaniosis canina en la comarca del Priorat (Tarragona)

Se investiga la presencia de anticuerpos anti-Leishmania mediante una técnica de «Dot-ELISA» en 1.328 muestras de sangre procedentes de 902 perros de la comarca del Priorat (Cataluña), importante foco de leishmaniosis canina. El umbral de positividad para la mencionada técnica (11800) se establece a partir de los datos obtenidos al realizar en paralelo cultivo y serología. Los resultados serológicos obtenidos permiten observar una tasa de prevalencia de la infección de 10,2%. Tan sólo el 49,8 % de los sueros estudiados son totalmente negativos. Al 40 % restante se le detecta anticuerpos anti-Leishmania a títulos inferiores al umbral establecido cuyo posible significado se discute.The presence of anti-Leishmania antibodies is studied in 1328 blood samples from 902 dogs from the Priorat region (Catalonia), an important focus of canine leúhmaniosú, by a Dot-ELISA technique. The cut-off (1/800)is established through the data obtained by serology and culture in parallel. The prevalence of seropositives observed was 10,2 %. Only 49,8 % of sera were completely negative. The remaining 40% had anti-Leishmania antibodies at titres below the cut- off, the possible significance of which is discused

Application of microsatellite genotyping to the study of a restricted Leishmania infantum focus: different genotype compositions in isolates from dogs and sand flies

Leishmania infantum polymorphism was studied by DNA microsatellite analysis of 110 L. infantum stocks (94 from dogs, 15 from sand flies, and 1 from a human visceral case) from a rural leishmaniasis-endemic area (Priorat) in northeastern Spain. Three microsatellites of the eight present in three fragments (internal transcribed spacer, Lm4, and Lm2) of L. infantum nuclear DNA are polymorphic inside the focus, resulting in 17 genotypes. Isolates from dogs and sand flies had different allelic compositions and shared only four genotypes. Microsatellite analysis is useful for L. infantum genotyping and epidemiologic tracking. Its application with strains from dogs and vectors in an area endemic for leishmaniasis shows the heterogeneous distribution of L. infantum in hosts living in sympatric conditions

Factors influencing the presence of sand flies in Majorca (Balearic Islands, Spain) with special reference to Phlebotomus pernicious, vector of Leishmania infantum

Background: Although the Mediterranean island of Majorca is an endemic area of leishmaniosis, there is a lack of up-to-date data on its sand fly fauna, the last report dating from 1989. The aim of the present study was to provide information on the current sand fly distribution, the potential environmental factors favoring the presence of Phlebotomus perniciosus and which areas are at risk of leishmaniosis. Methods: In July 2008 sand fly captures were carried out in Majorca with sticky castor oil interception traps. The capture stations were distributed in 77 grids (5x5 km2) covering the entire island. A total of 1,882 sticky traps were set among 111 stations. The characteristics of the stations were recorded and maps were designed using ArcGIS 9.2 software. The statistical analysis was carried out using a bivariate and multivariate logistic regression model. Results: The sand fly fauna of Majorca is composed of 4 species: Phlebotomus perniciosus, P sergenti, P. papatasi and Sergentomyia minuta. P. perniciosus, responsible for Leishmania infantum transmission, was captured throughout the island (frequency 69.4 %), from 6 to 772 m above sea level. Through logistic regression we estimated the probability of P. perniciosus presence at each sampling site as a function of environmental and meteorological factors. Although in the initial univariate analyses the probability of P. perniciosus presence appeared to be associated with a wide variety of factors, in the multivariate logistic regression model only altitude, settlement, aspect, drainage hole construction, adjacent flora and the proximity of a sheep farm were retained as positive predictors of the distribution of this species. Conclusions: P. perniciosus was present throughout the island, and thereby the risk of leishmaniosis transmission. The probability of finding P. perniciosus was higher at altitudes ranging from 51 to 150 m.a.s.l., with adjacent garrigue shrub vegetation, at the edge of or between settlements, and in proximity to a sheep farm

Importance of individual analysis of environmental and climatic factors affecting the density of Leishmania vectors living in the same geographical area: the example of Phlebotomus ariasi and P. perniciosus in northeast Spain.

The aim of the present study was to determine the role of specific environmental and climatic factors affecting the distribution and density of Phlebotomus ariasi and P. perniciosus, the proven vectors for Leishmania infantum in Spain. An entomological study was carried out in July 2006 in the province of Lleida with sticky traps set in their diurnal resting places at altitudes ranging from 86 to 1,755 m above the mean sea level (339 sites were sampled). Bivariate analysis revealed that factors such as altitude, bioclimatic zone, temperature, precipitation, sampling site (site relative to settlement, site situation, site category), wall vegetation, particular environment (in this case a natural park), general environment, adjacent natural vegetation and land cover were significantly associated with sand fly densities. The multivariate model for P. perniciosus revealed that its density was affected by site and land cover. Specifically, paved driveways correlated negatively with vector density (Incidence Risk Ratio (IRR): 0.41) and arable land cover correlated positively (IRR: 4.59). In the case of P. ariasi, a significant correlation was observed with the altitude and bioclimatic zone, with density increasing at >800 m above the mean sea level (IRR: 3.40) and decreasing in the meso-Mediterranean bioclimatic zone (IRR: 0.08). Both species were mostly found in agricultural and forest areas far from domestic environments. However, the two species correlated differently with altitude, bio-climate, vegetation, temperature and precipitation, which emphasises the importance of their individual analysis in studies regarding risk of leishmaniasis transmission