Multiple and spectrally robust photonic magic angles in reconfigurable α-MoO3 trilayers.

The emergence of a topological transition of the polaritonic dispersion in twisted bilayers of anisotropic van der Waals materials at a given twist angle-the photonic magic angle-results in the diffractionless propagation of polaritons with deep-subwavelength resolution. This type of propagation, generally referred to as canalization, holds promise for the control of light at the nanoscale. However, the existence of a single photonic magic angle hinders such control since the canalization direction in twisted bilayers is unique and fixed for each incident frequency. Here we overcome this limitation by demonstrating multiple spectrally robust photonic magic angles in reconfigurable twisted α-phase molybdenum trioxide (α-MoO3) trilayers. We show that canalization of polaritons can be programmed at will along any desired in-plane direction in a single device with broad spectral ranges. These findings open the door for nanophotonics applications where on-demand control is crucial, such as thermal management, nanoimaging or entanglement of quantum emitters.

Head trauma in the haemophilic child and management in a paediatric emergency department: Descriptive study.

INTRODUCTION: Haemophilia is one of the most common inherited bleeding disorders in the Emergency Department (ED). The most dangerous site of bleeding is the central nervous system. AIMS: To describe the characteristics of haemophiliacs arrived to our ED following a head trauma and to analyse the incidence of intracranial haemorrhage (ICH). MATERIALS AND METHODS: Retrospective, analytical, observational study, conducted in a Paediatric ED. We included haemophilic patients aged from birth to 16 years who consulted after a head trauma over a 6-year period. Data collected included age, type of haemophilia and head trauma, symptoms, prophylaxis status, CT imaging, treatment and number of visits to the ED. RESULTS: About 46 males and 85 episodes were analysed. The median age was 2.38 years. Severe haemophilia A was the most frequent type of disease (50%). All head injuries were mild, and the most frequent mechanism was a collision with an object (38.8%). In 62 episodes (72.9%) the patients were asymptomatic. The rest 23 events had symptomatology, being the most common headache (26%), emesis (21.7%) and drowsiness (17.4%). Head CT was obtained in 31 episodes, founding altered results in 10 (6 of them corresponding to ICH). All the patients with ICH had symptomatology. About 37 episodes required admission. CONCLUSION: Intracranial haemorrhage is one of the most dangerous events in haemophiliacs and it may occur after a head trauma. Our study suggests that, in case of head trauma, CT must be obtained in symptomatic patients and in those with additional risk factors. Asymptomatic patients must have prolonged observation.

Cutaneous leishmaniasis by Leishmania infantum: behind granulomatous lesions of unknown aetiology.

BACKGROUND: Cutaneous leishmaniasis (CL) is underestimated in Spain as in other European countries due to the polymorphism of its clinical manifestations and histopathological features discouraging doctors from suspecting leishmaniasis. Mucosal manifestations (ML) are misdiagnosed due to the fact that they often mimic cancer. OBJECTIVES: Given that leishmaniasis may be masked as different granulomatous diseases in Leishmania infantum endemic areas, the aim of this study was to verify this misdiagnosing and contributes to the improvement of CL/ML diagnosis. METHODS: A retrospective study involving formalin-fixed paraffin-embedded tissue biopsies with histopathological features of granulomatous lesions of unknown origin (GLUO) detected in 17 patients. This study included 13 patients with CL that was used as positive controls, nine patients with other confirmed diseases used as negative controls and seven patients with histological features suggestive of CL or ML without confirmation. Molecular analysis was blindly performed using two different PCR techniques. RESULTS: The PCR detected 15 CL cases in which the diagnosis was neither clinically nor histologically suspected. Leishmaniasis was confirmed in seven suspected patients in whom the classical techniques failed to detect the parasite. L. infantum was identified in all cases. A systematic review of CL cases in GLUO patients from European countries identified 45 reported cases. CONCLUSIONS: In L. infantum endemic areas, a high percentage of GLUO are due to Leishmania infection. The main consequences are delayed diagnosis and underestimation of the real incidence. PCR performed on paraffin-embedded tissue proved to be a reliable tool for diagnosis of CL/ML and must be performed routinely in any granulomatous dermatitis, even when the morphological features are no stereotypical of leishmaniasis.

Comparison of PCR-based methods for the diagnosis of cutaneous leishmaniasis in two different epidemiological scenarios: Spain and Morocco.

BACKGROUND: Cutaneous leishmaniasis (CL) is a disfiguring and stigmatising disease occurring in more than 70 countries across the world including Spain and Morocco. The use of sensitive tests that can differentiate Leishmania species is advised. OBJECTIVE: To evaluate the influence of the epidemiological scenario on the reliability of the PCR techniques and contribute to the selection of the most efficient one for CL diagnosis. METHODS: The sensitivities of parasitological methods and four PCRs were compared in cutaneous samples from 77 patients from Spanish (PSH) and Moroccan hospitals (PMH). Exudates and fresh or paraffin-embedded tissue biopsies were used. RESULTS: None of the PCRs used in this study allowed the diagnosis of all CL cases, showing also some drawbacks. Lmj4/Uni21-PCR displayed the best sensitivity with PMH, but it did not provide positive results in PSH with CL confirmed by other PCRs. Conversely, JW13/JW14-PCR and L. infantum-PCR-ELISA displayed good sensitivities with PSH that were not achieved with PMH. Nested-ITS-1-PCR did not show enough sensitivity with paraffin-embedded tissue biopsies. False-negative results were obtained in 19% of PSH due to unspecific hybridizations of ITS-1 primers with human chromosome1. CONCLUSIONS: PCR should be routinely used in patients with cutaneous lesions compatible with CL and furthermore, the combination of two PCR techniques is advisable. The selection of these PCRs will be influenced by the epidemiological scenario: In areas where L. infantum is endemic, the use of the PCR-ELISA joint with JW13/JW14-PCR seems an appropriate choice, whereas in areas such as Morocco, Lmj4/Uni21 and ITS-1 provide satisfactory results.

Phlebotomus langeroni Nitzulescu (Diptera, Psychodidae) a new vector for Leishmania infantum in Europe.

Burrows of the wild rabbit, Oryctolagus cuniculus, a lagomorph that has been recently suggested as a Leishmania infantum reservoir, constitute an unspoilt biotope in phlebotomine studies in Europe. We hypothesize that Phlebotomus langeroni, a proven vector of L. infantum in North Africa, is associated with rabbits and may have been overlooked in Europe. Sandfly captures were carried out with CDC light traps in an L. infantum endemic area of southern Spain with a high density of lagomorphs and a large numbers of burrows. The stable, permanent, and highly abundant presence of P. langeroni was assessed. After morphological identification, this sandfly species was characterized by comparing it with P. perniciosus and other P. langeroni populations from North Africa through molecular techniques. P. langeroni had not been found in southern Spain to date, despite being a highly investigated area, except for this particular biotope. Its activity period turned out to begin in mid-July, ending in late October, accounting for a maximum activity during this month. This study shows that P. langeroni is associated with the existence of rabbit burrows and has been overlooked in Europe. L. infantum DNA was found in almost half of the female specimens (47.6%) captured inside a biotope where wild rabbits are infected as well.

SiGe layer thickness effect on the structural and optical properties of well-organized SiGe/SiO2 multilayers.

In this work, we report on the production of regular (SiGe/SiO2)20 multilayer structures by conventional RF-magnetron sputtering, at 350 °C. Transmission electron microscopy, scanning transmission electron microscopy, raman spectroscopy, and x-ray reflectometry measurements revealed that annealing at a temperature of 1000 °C leads to the formation of SiGe nanocrystals between SiO2 thin layers with good multilayer stability. Reducing the nominal SiGe layer thickness (t SiGe) from 3.5-2 nm results in a transition from continuous SiGe crystalline layer (t SiGe ∼ 3.5 nm) to layers consisting of isolated nanocrystals (t SiGe ∼ 2 nm). Namely, in the latter case, the presence of SiGe nanocrystals ∼3-8 nm in size, is observed. Spectroscopic ellipsometry was applied to determine the evolution of the onset in the effective optical absorption, as well as the dielectric function, in SiGe multilayers as a function of the SiGe thickness. A clear blue-shift in the optical absorption is observed for t SiGe ∼ 2 nm multilayer, as a consequence of the presence of isolated nanocrystals. Furthermore, the observed near infrared values of n = 2.8 and k = 1.5 are lower than those of bulk SiGe compounds, suggesting the presence of electronic confinement effects in the nanocrystals. The low temperature (70 K) photoluminescence measurements performed on annealed SiGe/SiO2 nanostructures show an emission band located between 0.7-0.9 eV associated with the development of interface states between the formed nanocrystals and surrounding amorphous matrix.

The sesquiterpene (-)-α-bisabolol is active against the causative agents of Old World cutaneous leishmaniasis through the induction of mitochondrial-dependent apoptosis.

Cutaneous leishmaniasis treatment remains challenging due to the absence of a satisfactory treatment. The screening of natural compounds is a valuable strategy in the search of new drugs against leishmaniasis. The sesquiterpene (-)-α-bisabolol is effective in vivo against visceral leishmaniasis due to Leishmania infantum, but its mechanism of action remains elusive. The aim of this study is to validate this promising compound against the causative species of Old World cutaneous leishmaniasis and to get an insight into its antileishmanial mode of action. The compound was evaluated on L. tropica promastigotes and intracellular amastigotes using bone marrow-derived macrophages and its cytotoxicity was evaluated on L929 fibroblasts. The reactive oxygen species generation was evaluated using a sensitive probe. Mitochondrial depolarization was assessed evaluating the fluorescence due to rhodamine 123 in a flow cytometer. Apoptosis was investigated by measuring the fluorescence due to annexin V and propidium iodide in a flow cytometer. The ultrastructure of treated promastigotes and intracellular amastigotes was analysed through transmission electron microscopy. (-)-α-Bisabolol was active against L. tropica intracellular amastigotes displaying an inhibitory concentration 50 % of 25.2 µM and showing low cytotoxicity. This compound induced time and dose-dependent oxidative stress, mitochondrial depolarization and phosphatidilserine externalization (a marker of apoptosis). These effects were noticed at a low concentration and short exposure time. In the ultrastructural analyses, the treated parasites showed mitochondrial disruption, presence of electron-dense structures and chromatin condensation. These results suggest that this natural compound induces oxidative stress and mitochondrial-dependent apoptosis on Leishmania without disturbing the plasma membrane.

Differential ecological traits of two Phlebotomus sergenti mitochondrial lineages in southwestern Europe and their epidemiological implications.

OBJECTIVES: The introduction of leishmaniasis in a new area requires a well-established population of the sandfly vector species of the parasite. No autochthonous cases of anthroponotic cutaneous leishmaniasis have been detected in southwestern Europe, and Leishmania infantum is the only causative agent of leishmaniasis in this area. Phlebotomus sergenti, the main vector of Leishmania tropica, is commonly found in the Iberian Peninsula at sufficient densities to be able to act as a vector. It is characterised by high genetic diversity and classified in four mitochondrial lineages. Our aim was to analyse the composition and distribution of P. sergenti mitochondrial lineages in southwestern Europe given the possibility of phenotypic differences of biomedical importance between them. METHODS: Sandflies were captured in the Iberian Peninsula and on the Canary and Balearic Islands. Mitochondrial lineage identification of 137 P. sergenti was performed using a novel PCR-RFLP that avoids the necessity of gene sequencing. RESULTS: Two lineages were evidenced, the typical Iberian one (lineage I) and another, held in common with North Africa (lineage III), that show a distinctive distribution. P. sergenti lineage I shows a better correlation to the bioclimatic diversity in southwestern Europe. Conversely, P. sergenti lineage III prefers warmer temperatures and less precipitation, which are typical of the Mediterranean. CONCLUSION: Lineage I seems to have adaptive advantages given its wider tolerance to temperature and altitude than lineage III, and it would seem more suitable to lead a potential geographical expansion towards the rest of Europe.

Leishmania infantum in wild rodents: reservoirs or just irrelevant incidental hosts?

Wild rodents constitute a very large biomass of potential reservoirs for Leishmania spp. Therefore, an epidemiological study was carried out in a well-known focus of canine leishmaniasis from southern Spain, with the objective of detecting and characterizing Leishmania infantum infection in wild rodents. Blood, liver, spleen, bone marrow, and skin from 37 rodents (24 Apodemus sylvaticus, 9 Rattus rattus, and 4 Mus musculus) were analyzed by optical microscopy, culture, and two different polymerase chain reactions. L. infantum DNA was found in 27% (10 out of 37) of the trapped rodents, in a variety of tissues: bone marrow, spleen, or healthy skin (ear lobe). High prevalences of L. infantum infection were found in the three investigated rodent species. The presence of other trypanosomatids was also evidenced. These rodent species are abundant, widely distributed in Europe, and have a long enough lifespan to overcome the low sandfly activity season. They live in a suitable habitat for sandflies and serve as blood sources for these insects, which can become infected when induced to feed on Leishmania-infected animals. Whether they are reservoirs or just irrelevant incidental hosts, it is clear that the epidemiology of L. infantum is more complex than previously thought, and so is its control. The classic epidemiological cycle dog-sandfly-human is turning into a network of animal species that collaborate with the dog in the maintenance of the parasite under natural conditions and probably showing local differences.

Changing trends in the epidemiology of hip fracture in Spain.

UNLABELLED: Temporal trends in hip fracture incidence have recently been reported in some developed countries. Such data in Spain has previously been incomplete; this study reports the stratified incidence of hip fractures in people over 65 in Spain during the last 14 years. INTRODUCTION: The main objective is to establish whether temporal trends in hip fracture incidence in Spain exist. METHODS: Ecological study with data from hospital discharges nationwide. The study includes patients aged ≥ 65 years during a 14-year period (1997-2010). The analysis compares two periods of four years: 1997-2000 (P1) and 2007-2010 (P2). RESULTS: There were 119,857 fractures in men and 415,421 in women. Comparing periods (P1 vs P2) over 10 years, the crude incidence rate/100,000 inhabitant/year increased an average of 2.3%/year in men and 1.4% in women. After adjustment, the rate increased an average of 0.4%/year in men (p < 0.0001), but decreased 0.2%/year in women (p < 0.0001). In men, younger than 85, the decrease was not significant except in 70-74 years, and from 80 years, the adjusted rate increases significantly (p < 0.0001). In women under 80 years of age, the decrease in adjusted rate was significant; there was no change in 80-84 years, and the adjusted rate increased significantly in individuals 85 years and older (p < 0.0001). Mortality rates declined by 22% in both sexes, and the index of overaging population rises 30.1 % in men and 25.2% in women. CONCLUSIONS: This study supports other international studies by showing changes in the incidence of hip fractures after age-population adjustment, which denotes a decrease in the younger age groups and among women and shows an increase in both groups over 85 years. The increase in the crude incidence rate of hip fracture in Spain reflects changes in population structure.

Epidemiology and molecular identification of Anisakis pegreffii (Nematoda: Anisakidae) in the horse mackerel Trachurus trachurus from northern Morocco.

Anisakis infection parameters were studied in horse mackerel (Trachurus trachurus) taken from two areas of northern Morocco (Tetouan and Tangier), which showed a mean prevalence of 54.9%. Identification of the ITS1-5.8S-ITS2 fragment by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) showed A. pegreffii to be the dominant species; no A. simplex s.s. were detected. The presence of A. pegreffii in horse mackerel was not influenced by the sex (P = 0.46) or catch area (Atlantic versus Mediterranean, P = 0.52) of the fish, but was significantly related to their length, weight, liver weight and gonad weight, and to the season of their capture (P < 0.05). A low prevalence (8.6%) and mean intensity (1.0) was detected in the muscle, probably related to the reduced ability of A. pegreffii to penetrate muscle. The risk of the presence of A. pegreffii in the muscle was fivefold higher in fish caught during the summer than during any other season. Susceptible members of the human population can minimize the risk of infection by avoiding the consumption of larger horse mackerel specimens during the summer.

Predicting the risk of an endemic focus of Leishmania tropica becoming established in South-Western Europe through the presence of its main vector, Phlebotomus sergenti Parrot, 1917.

The aim of the study was the construction of risk maps for exposure to Phlebotomus sergenti, the main vector of Leishmania tropica, with a view to identifying hot spots for the potential establishment of this parasite in the southwest of Europe. Data were collected on the presence/absence of this vector and the ecological and climatic characteristics of 662 sampling sites located in the southeast, centre and northeast of the Iberian Peninsula (south-western Europe). The environmental factors associated with the distribution of P. sergenti were determined. The best predictors for the presence of this dipteran were 'altitude', 'land use', 'land surface temperature', 'aspect', 'adjacent land cover', 'absence of vegetation in wall' and the 'absence of PVC pipes in the drainage holes of retaining walls'. Risk maps for exposure to the vector were drawn up based on these variables. The validation of the predictive risk model confirmed its usefulness in the detection of areas with a high risk of P. sergenti being present. These locations represent potential hot spots for an autochthonous focus of L. tropica becoming established. The risk maps produced for P. sergenti presence revealed several areas in the centre and south of the Iberian Peninsula to be the most prone to this process, which would make it possible for the disease to enter south-western Europe.

Twist-tunable polaritonic nanoresonators in a van der Waals crystal.

Optical nanoresonators are key building blocks in various nanotechnological applications (e.g., spectroscopy) due to their ability to effectively confine light at the nanoscale. Recently, nanoresonators based on phonon polaritons (PhPs)-light coupled to lattice vibrations-in polar crystals (e.g., SiC, or h-BN) have attracted much attention due to their strong field confinement, high quality factors, and their potential to enhance the photonic density of states at mid-infrared (mid-IR) frequencies, where numerous molecular vibrations reside. Here, we introduce a new class of mid-IR nanoresonators that not only exhibit the extraordinary properties previously reported, but also incorporate a new degree of freedom: twist tuning, i.e., the possibility of controlling their spectral response by simply rotating the constituent material. To achieve this result, we place a pristine slab of the van der Waals (vdW) α-MoO3 crystal, which supports in-plane hyperbolic PhPs, on an array of metallic ribbons. This sample design based on electromagnetic engineering, not only allows the definition of α-MoO3 nanoresonators with low losses (quality factors, Q, up to 200), but also enables a broad spectral tuning of the polaritonic resonances (up to 32 cm-1, i.e., up to ~6 times their full width at half maximum, FWHM ~5 cm-1) by a simple in-plane rotation of the same slab (from 0 to 45°). These results open the door to the development of tunable and low-loss IR nanotechnologies, fundamental requirements for their implementation in molecular sensing, emission or photodetection applications.

Sensitization to Anisakis simplex species in the population of northern Morocco.

OBJECTIVE: To investigate sensitization to third-stage Anisakis simplex larvae in a randomly selected population in northern Morocco. METHODS: We studied sera obtained from clinical analysis laboratories in Tangier and Tetuouan and from fishermen at Tangier port. The age of the study population ranged from 6 to 83 years. ImmunoCAP and immunoblotting techniques were used to determine total and specific immunoglobulin (Ig) E values and the chi2 and Fisher exact tests were applied to analyze relationships between study variables. RESULTS: A seroprevalence of 5.1% was found, with a higher percentage of positive sera in the 31-to-43-year age group. Sensitization was not significantly associated with the origin, sex, occupation, or age of the individuals studied. In sera positive by InmunoCAP, immunoblotting studies detected numerous bands of between 7 kDa and >209 kDa, with a predominance of bands in the approximately 20-kDa to 24-kDa range. CONCLUSIONS: Although no cases of human anisakiasis have been reported in Morocco to date, part of a randomly selected population in Northern Morocco shows sensitization to A simplex proteins.

Risk maps for the presence and absence of Phlebotomus perniciosus in an endemic area of leishmaniasis in southern Spain: implications for the control of the disease.

The aim of this study was to construct risk maps for the presence of the dominant Leishmania infantum vector, P. perniciosus, and check its usefulness (a) to predict the risk of canine leishmaniasis and (b) to define effective leishmaniasis control measures. We obtained data for the presence/absence of P. perniciosus at 167 sampling sites in southern Spain, from which we also took a series of ecological and climate-related data. The probability of P. perniciosus presence was estimated as a function of these environmental variables and generated spatial risk maps. Altitude, land use and drainage hole features (with or without PVC piping) were retained as the only predictors for the distribution of this vector species. Drainage hole features in retaining walls, with or without PVC piping, produce significant variations in the probability of P. perniciosus presence, varying from 2·3 to 91·8% if PVC piping is absent and from 0·4 to 66·5% if all holes have PVC piping. It was concluded that the use of PVC piping in drainage holes could help to reduce leishmaniasis transmission.

Enabling propagation of anisotropic polaritons along forbidden directions via a topological transition.

Polaritons with directional in-plane propagation and ultralow losses in van der Waals (vdW) crystals promise unprecedented manipulation of light at the nanoscale. However, these polaritons present a crucial limitation: their directional propagation is intrinsically determined by the crystal structure of the host material, imposing forbidden directions of propagation. Here, we demonstrate that directional polaritons (in-plane hyperbolic phonon polaritons) in a vdW crystal (α-phase molybdenum trioxide) can be directed along forbidden directions by inducing an optical topological transition, which emerges when the slab is placed on a substrate with a given negative permittivity (4H-silicon carbide). By visualizing the transition in real space, we observe exotic polaritonic states between mutually orthogonal hyperbolic regimes, which unveil the topological origin of the transition: a gap opening in the dispersion. This work provides insights into optical topological transitions in vdW crystals, which introduce a route to direct light at the nanoscale.

Planar refraction and lensing of highly confined polaritons in anisotropic media.

Refraction between isotropic media is characterized by light bending towards the normal to the boundary when passing from a low- to a high-refractive-index medium. However, refraction between anisotropic media is a more exotic phenomenon which remains barely investigated, particularly at the nanoscale. Here, we visualize and comprehensively study the general case of refraction of electromagnetic waves between two strongly anisotropic (hyperbolic) media, and we do it with the use of nanoscale-confined polaritons in a natural medium: α-MoO3. The refracted polaritons exhibit non-intuitive directions of propagation as they traverse planar nanoprisms, enabling to unveil an exotic optical effect: bending-free refraction. Furthermore, we develop an in-plane refractive hyperlens, yielding foci as small as λp/6, being λp the polariton wavelength (λ0/50 compared to the wavelength of free-space light). Our results set the grounds for planar nano-optics in strongly anisotropic media, with potential for effective control of the flow of energy at the nanoscale.

Systematic Review of Light-Based Treatments for Hidradenitis Suppurativa. / Revisión sistemática de las terapias con luz en el tratamiento de la hidradenitis supurativa.

Treatment options for hidradenitis suppurativa include light-based therapy. This systematic review aimed to update our understanding of the efficacy, effectiveness and safety of these treatments for hidradenitis suppurativa by evaluating the literature published since the 2015 Cochrane review on this topic. We conducted an electronic search of the following databases: MEDLINE, EMBASE, University of York Centre for Reviews and Dissemination database, Cochrane Database of Systematic Reviews, Cochrane Skin Group Specialised Skin Register, University of Nottingham's Centre of Evidence Based Dermatology database, and TESEO. The systematic review included 6 case series, 3 systematic reviews, and 2 clinical trials on the use of conventional and intralesional photodynamic therapy, intense pulsed light therapy, and Nd:YAG, carbon dioxide, and diode laser therapy for hidradenitis suppurative in 248 patients.

Site-controlled lateral arrangements of InAs quantum dots grown on GaAs(001) patterned substrates by atomic force microscopy local oxidation nanolithography.

In this work, we present a fabrication process that combines atomic force microscopy (AFM) local oxidation nanolithography and molecular beam epitaxy (MBE) growth techniques in order to control both the nucleation site and number of InAs quantum dots (QDs) inside different motifs printed on GaAs(001) substrates. We find that the presence of B-type slopes (As terminated) inside the pattern motifs is the main parameter for controlling the selectivity of the pattern for InAs growth. We demonstrate that either single InAs QDs or multiple InAs QDs in a lateral arrangement (LQDAs) can be obtained, with a precise control in their position and QD number, simply by varying the fabricated oxide length along the [110] direction.

Effectiveness of the sesquiterpene (-)-α-bisabolol in dogs with naturally acquired canine leishmaniosis: an exploratory clinical trial.

The use of natural products is a promising approach for treating visceral leishmaniosis. (-)-α-Bisabolol is a sesquiterpene that have been proved active in vivo on Leishmania infantum-infected mice without showing toxicity. A single-centre, parallel-group, randomized, exploratory study was designed to assess its efficacy in a canine leishmaniosis model involving naturally infected dogs. In this clinical trial, 12 dogs were allocated into two groups and were treated with either meglumine antimoniate (100 mg/kg) through subcutaneous route or (-)-α-bisabolol (30 mg/kg) through oral route for two treatment series of 30 days, separated by a 30-day interval. A 4-month follow-up period was established as well. Parasite loads in bone marrow, lymph node and blood were estimated through quantitative PCR. Antibody titres were determined through immunofluorescence antibody test and cytokine expression values were estimated through real-time reverse transcription-PCR. Treatment safety was assessed through the evaluation of weight, gastrointestinal alterations and hematological and biochemical parameters in blood. Analyses were performed before and after treatment, and after a 4-months follow-up period. Treatment with the sesquiterpene was effective at decreasing parasite loads and increasing gamma-interferon expression level. Dogs treated with (-)-α-bisabolol did not show any toxicity sign. These results were better than those obtained using the reference drug, meglumine antimoniate. The natural compound seemed to induce a Th1 immune response that led to parasitological and clinical improvement without showing any safety issue, suggesting a high potential for the treatment of canine and human visceral leishmaniosis.