RESUMO
Abstract Leptospirosis is a neglected zoonosis that is widely distributed in the world. Although it is endemic in Argentina, prevalence remains unknown. The aims of the study were: (i) to determine the prevalence of leptospirosis in humans from a rural community in Tandil Argentina, (ii) to identify infecting Leptospira spp. serogroups, (iii) to identify factors associated with the infection, (iv) to estimate the population attributable fraction (PAF) of the risk factors and (v) to determine the spatial patterns of disease presentation and related risk factors. Blood samples from 202 participants were collected. A survey was conducted to obtain clinical and epidemiological data. Serological testing was performed by the microscopic agglutination test (MAT). Univariate and multivariate methods were applied to evaluate associations. Spatial clusters were investigated for seroprevalence and risk factors. Antibodies were found in 32.2% of participants (95% CI: 25.8-39.1). The most prevalent serogroup was Hebdomadis followed by Sejroe; Icterohaemorrhagiae; Tarassovi and Canicola. Living at lower altitudes (OR: 13.04; 95% CI: 2.60-65.32); not having access to water supply network (OR: 2.95; 95% CI: 1.30-6.69); living close to flooded streets (OR: 2.94; 95% CI: 1.14-7.69) and practicing water sports (OR: 3.12; 95% CI: 1.12-8.33) were associated with seropositivity. Factors related with housing characteristics, services and infrastructure had the higher PAF (from 17% to 81%). A spatial cluster with higher rates of positivity and of the main risk factors was determined. This work contributes useful data for specific preventive measures that should be implemented for the control of the disease.
Resumen La leptospirosis es una enfermedad desatendida, ampliamente distribuida a nivel mundial. Aunque es endémica en Argentina, su prevalencia es desconocida. Los objetivos de este estudio fueron los siguientes: (i) determinar la prevalencia de leptospirosis humana en comunidades rurales del partido de Tandil (Argentina), (ii) identificar serogrupos infectantes de Leptospira spp., (iii) identificar factores de riesgo asociados, (iv) estimar la fracción atribuible poblacional (FAP) de los factores de riesgo y (v) determinar los patrones espaciales de la enfermedad y de los factores de riesgo. Se tomaron muestras de sangre a 202 personas, y se registró información clínica y epidemiológica. El diagnóstico se realizó por microaglutinación (MAT). Para evaluar asociaciones, se utilizaron métodos univariados y multivariados. Se estudiaron clusters espaciales de la seroprevalencia y de los factores de riesgo. El 32,2% de los participantes (IC 95%: 25,8-39,1) presentaron anticuerpos. Los serogrupos más prevalentes fueron Hebdomadis, Sejroe, Icterohaemorrhagiae, Tarassovi y Canicola. Vivir a menores altitudes (OR: 13,04; IC 95%: 2,60-65,32) y cerca de calles inundables (OR: 2,94; IC 95%: 1,14-7,69), la falta de acceso a agua de red (OR: 2,95; IC 95%: 1,30-6,69) y la práctica de deportes acuáticos (OR: 3,12; IC 95%: 1,12-8,33) estuvieron asociados con la seropositividad. Factores relacionados con las características de las viviendas, los servicios y la infraestructura tuvieron mayor proporción de FAP (17 al 81%). Se encontró un área de mayor riesgo de presentación de individuos seropositivos y de los principales factores de riesgo. Este trabajo provee información útil para generar medidas preventivas específicas que podrían ser aplicadas para controlar esta enfermedad.
RESUMO
Leptospirosis is a neglected zoonosis that is widely distributed in the world. Although it is endemic in Argentina, prevalence remains unknown. The aims of the study were: (i) to determine the prevalence of leptospirosis in humans from a rural community in Tandil Argentina, (ii) to identify infecting Leptospira spp. serogroups, (iii) to identify factors associated with the infection, (iv) to estimate the population attributable fraction (PAF) of the risk factors and (v) to determine the spatial patterns of disease presentation and related risk factors. Blood samples from 202 participants were collected. A survey was conducted to obtain clinical and epidemiological data. Serological testing was performed by the microscopic agglutination test (MAT). Univariate and multivariate methods were applied to evaluate associations. Spatial clusters were investigated for seroprevalence and risk factors. Antibodies were found in 32.2% of participants (95% CI: 25.8-39.1). The most prevalent serogroup was Hebdomadis followed by Sejroe; Icterohaemorrhagiae; Tarassovi and Canicola. Living at lower altitudes (OR: 13.04; 95% CI: 2.60-65.32); not having access to water supply network (OR: 2.95; 95% CI: 1.30-6.69); living close to flooded streets (OR: 2.94; 95% CI: 1.14-7.69) and practicing water sports (OR: 3.12; 95% CI: 1.12-8.33) were associated with seropositivity. Factors related with housing characteristics, services and infrastructure had the higher PAF (from 17% to 81%). A spatial cluster with higher rates of positivity and of the main risk factors was determined. This work contributes useful data for specific preventive measures that should be implemented for the control of the disease.
Assuntos
Leptospira , Leptospirose , Humanos , População Rural , Estudos Soroepidemiológicos , Argentina/epidemiologia , Leptospirose/epidemiologia , Anticorpos Antibacterianos , Fatores de Risco , Análise EspacialRESUMO
Praziquantel (PZQ) is widely used in the treatment of several parasitic infections in both humans and animals, and is the first choice in the treatment of Schistosomiasis in humans. However, PZQ is a hydrophobic drug, and its low aqueous solubility has been a significant barrier to the development of oral liquid formulations that may provide improved bioavailability, pharmacokinetic profile, and compliance. The aim of this study was thus (i) to develop an oil-in-water (O/W) nanoemulsion(NE)-based platform for the delivery of PZQ in liquid form; (ii) to study the transport of PZQ formulated in NEs across an in vitro model of the intestinal epithelium; and (iii) to determine the toxicity profile of the NEs and their individual components on the model epithelium. We also sought to compare the toxicity and transport profiles of the proposed formulations, with those of PZQ in a solid nanostructured particle system - PZQ encapsulated within poly(lactic acid-co-glycolic acid) (PLGA) nanoparticles (NPs). Two essential oils were selected as the oil phase in the NEs, namely clove and orange. The NEs were prepared with selected non-ionic surfactants and had high solubilization capacity towards PZQ, and average diameters well below 100nm. The NEs also showed long term physical stability at both simulated physiological and gastric conditions. NEs with clove oil (NEC-PZQ) were observed to have a lower cytotoxic profile when compared to the orange oil NEs (NEO-PZQ). The results also showed that the transport of PZQ formulated within such nanostructured systems was much greater and larger rates across confluent and polarized Caco-2 monolayers when compared to free PZQ. Interestingly, little difference in PZQ transport between the NEs and NPs was observed. These results point to NEs as potentially viable strategies for the liquid formulation of PZQ in particular, and more broadly to the formulation of other hydrophobic therapeutics that may be employed in the fight against important neglected diseases such as Schistosomiasis, which alone affects more than 240 million people worldwide.
