Molecular identification of Bartonella spp. and Rickettsia felis in fox fleas, Chile

Seventy-five flea pools (one to ten fleas per pool) from 51 Andean foxes (Lycalopex culpaeus) and five South American grey foxes or chillas (Lycalopex griseus) from the Mediterranean region of Chile were analyzed for the presence of DNA of Bartonella spp. and Rickettsia spp. through quantitative real-time PCR for the nouG and gltA genes, respectively. Positive samples were further characterized by conventional PCR protocols, targeting gltA and ITS genes for Bartonella, and gltA, ompA, and ompB genes for Rickettsia. Bartonella was detected in 48 % of the Pulex irritans pools (B. rochalimae in three pools, B. berkhoffii in two pools, B. henselae in one pool), and 8 % of the Ctenocephalides felis felis pools (B. rochalimae, one pool). Rickettsia was confirmed in 11 % of P. irritans pools and 92 % of the Ct. felis pools. Characterization confirmed R. felis in all sequenced Rickettsia-positive pools. All Ct. canis pools were negative. A Ct. felis pool from a wild-found domestic ferret (Mustela putorius furo) also resulted positive for R. felis. Although opportunistic, this survey provides the first description of zoonotic pathogens naturally circulating in fleas parasitizing Chilean free-living carnivores

Spirocerca lupi in the stomach of two Andean foxes (Lycalopex culpaeus) from Chile

The genus Spirocerca includes nematodes that parasitize the stomach and the oesophagus of carnivores, chiefly canids. Herein, we provide new data about the morphological, histopathological, and molecular characterization of Spirocerca sp. in Andean foxes (Lycalopex culpaeus) in Chile. Intact immature worms, identified as Spirocerca sp., were recovered in the lumen of the stomach from two foxes. Histologically, worms morphologically consistent with spirurid nematodes were present within the wall of the stomach and surrounded by nodular areas of inflammation with central necrotic debris. Molecular analysis of the cox1 gene yielded 19 sequences and 5 nucleotide sequence types with 99.95 to 99.98% similarity, being shared between both foxes. Nucleotide similarity ranged from 93.1 (with genotype 2 of S. lupi and S. vulpis) to 95.8% (with genotype 1 of S. lupi), a higher similarity than noted from sequences of S. lupi from an Andean fox from Peru (91.0 to 93.3%). However, the Poisson Tree Processes for species delineation did not support the existence of a new species Spirocerca. Phylogenetic and nucleotide analyses suggest that these specimens belong to a new variant or genotype of S. lupi or to a cryptic species. Whether the presence of the worms in the stomach has to do with genotypic differences in parasites or host or some combination is uncertain. Spirocerca lupi has never been found in Chilean dogs and must be investigated

Hacia un control más eficiente de parásitos gastrointestinales de caprinos del árido mendocino

La producción caprina comprende una explotación ganadera muy extendida, usualmente relacionada a poblaciones rurales marginadas geográficamente y de escasos recursos. Además de la escasa alimentación de los animales, una de las principales causas de disminución de la productividad son los parásitos gastrointestinales. A pesar de esto y de que Mendoza es una zona de fuerte producción caprina, existen pocos reportes regionales sobre las parasitosis presentes, lo cual estimula prácticas de control basadas más en el conocimiento empírico y el tradicionalismo que en el saber científico. Este trabajo se realizó en una zona del árido mendocino con el fin de describir las cargas parasitarias presentes en esas áreas, ya que representan gran parte del ecosistema de la provincia

Parásitos gastrointestinales en caprinos de las distintas regiones productivas de la provincia de Mendoza

La cría caprina en Argentina se realiza bajo un sistema extensivo, con pastoreo en campos naturales, escasez de agua de bebida y precarias infraestructuras de trabajo. La importancia de la producción caprina radica en la eficiencia de la cabra en convertir alimentos de baja calidad en carne de alto valor biológico. Mendoza cuenta actualmente con 662.272 cabezas caprinas, considerándose la segunda provincia más importante. En su territorio, esta explotación se realiza en tres zonas diferenciadas que agrupan a los departamentos de mayor importancia: 1) Noreste (Lavalle), 2) Valle de Uco (Tunuyán, Tupungato y San Carlos) y 3) Zona Sur (Malargüe y San Rafael). Existen diversos factores que pueden disminuir la producción y se considera que las parasitosis gastrointestinales son unas de las principales causas de pérdida. El objetivo de este estudio es determinar la presencia de parásitos gastrointestinales y su prevalencia en las distintas zonas de producción caprina

Liver fluke (Fasciola hepatica) naturally infecting introduced European brown hare (Lepus europaeus) in northern Patagonia: phenotype, prevalence and potential risk

ARTÍCULO PUBLICADO EN REVISTA EXTERNA. Fascioliasis has recently been included in the WHO list of Neglected Zoonotic Diseases. Besides being a major veterinary health problem, fascioliasis has large underdeveloping effects on the human communities affected. Though scarcely considered in fascioliasis epidemiology, it is well recognized that both native and introduced wildlife species may play a significant role as reservoirs of the disease. The objectives are to study the morphological characteristics of Fasciola hepatica adults and eggs in a population of Lepus europaeus, to assess liver fluke prevalence, and to analyze the potential reservoir role of the European brown hare in northern Patagonia, Argentina, where fascioliasis is endemic. Measures of F. hepatica found in L. europaeus from northern Patagonia demonstrate that the liver fluke is able to fully develop in wild hares and to shed normal eggs through their faeces. Egg shedding to the environment is close to the lower limit obtained for pigs, a domestic animal whose epidemiological importance in endemic areas has already been highlighted. The former, combined with the high prevalence found (14.28%) suggest an even more important role in the transmission cycle than previously considered. The results obtained do not only remark the extraordinary plasticity and adaptability of this trematode species to different host species, but also highlight the role of the European brown hare, and other NIS, as reservoirs capable for parasite spillback to domestic and native cycle, representing a potentially important, but hitherto neglected, cause of disease emergence. Sitio de la revista: https://pubmed.ncbi.nlm.nih.gov/26204194

Capacidad de transmisión de Fasciola hepatica de lymnaeidos de la provincia de Mendoza

La fascioliasis es una enfermedad producida por trematodos hepáticos del género Fasciola (trematoda: Fasciolidae). Para completar su ciclo, estos gusanos aplanados necesitan caracoles acuáticos de la familia Lymnaeidae. Esta enfermedad no sólo produce cuantiosas pérdidas a la ganadería, sino que también es una importante zoonosis que afecta a millones de personas en América, Europa, África, Asia y Oceanía. Tal es la situación actual, que la Organización Mundial de la Salud (OMS) la considera dentro de las 17 enfermedades desatendidas y dicta que deben de priorizarse las acciones para su control. Es en zonas andinas donde se encuentran las más altas prevalencias de fascioliasis humana en el mundo. Estudios recientes hechos por nuestro grupo de investigación indican que, en Argentina, la casuística humana es muy superior a la supuesta previamente. Las zonas andinas de Mendoza son endémicas para la fascioliasis animal y se han descripto casos humanos. Sin embargo se desconoce la capacidad vectorial, que representa el número de contactos potencialmente infectivos de una población de mosquitos por persona infectada por unidad de tiempo, la cual es una información necesaria para conocer la epidemiología y desarrollar estrategias de control. Determinar la capacidad de transmisión de Fasciola hepatica de las distintas poblaciones de lymnaeidos de zonas andinas de la provincia de Mendoza

Large-scale survey for canine vector-borne parasites in free-ranging dogs and foxes from six diverse bioclimatic regions of Chile

Chile is a large country with a marked range of climate conditions that make it an ideal scenario for the study of vector-borne parasites (VBPs); however, knowledge about their distribution is limited to a few confined areas of this country. The presence of Hepatozoon spp., piroplasmids, Leishmania spp. and filarioids was investigated through molecular and serological methods in blood and serum samples of 764 free-ranging rural dogs, 154 Andean foxes (Lycalopex culpaeus), and 91 South American grey foxes (Lycalopex griseus) from six bioclimatic regions across Chile. Hepatozoon spp. DNA was exclusively detected in foxes (43% prevalence), including sequences closely related to Hepatozoon felis (24.1%; only Andean foxes), Hepatozoon americanum (16.2%; only grey foxes), and Hepatozoon canis (1.25%; in one grey fox). Risk factor assessment identified a higher probability of Hepatozoon infection in juvenile foxes. DNA of piroplasmids was detected in 0.7% of dogs (Babesia vogeli) but in no fox, whilst antibodies against Babesia sp. were detected in 24% of the dogs and 25% of the foxes, suggesting a wider circulation of canine piroplasmids than previously believed. A positive association between the presence of antibodies against Babesia and high Rhipicephalus sanguineus sensu lato burden was observed in dogs. Leishmania spp. DNA and antibodies were detected in 0.8% and 4.4% of the dogs, respectively. Acanthocheilonema reconditum was the only blood nematode detected (1.5% of the dogs and no fox). Differences in prevalence among bioregions were observed for some of the VBPs. These results expand our knowledge about the occurrence of vector-borne parasites in Chile, some of which are firstly reported herein. This information will facilitate the diagnosis of vector-borne diseases in domestic dogs and improve the control measures for both domestic and wild canids

Distribution, transmission, and risk factors of infection with canine vector-borne pathogens in wild foxes and free-ranging dogs in Chile

Canine vector-borne pathogens (CVBP) distribution tends to be circumscribed to certain areas with climatic features where their vectors are able to persist. In this aspect, Chile possesses a marked variety of bioclimates that provides an ideal scenario to study the distribution of vector-borne pathogens, considering that ticks of the Rhipicephalus sanguineus species group are widely distributed in the country. Despite this, information about the presence, distribution, and impact of CVBP in domestic and wild canines in Chile is very scarce. In this study, blood and serum samples of 981 dogs, 155 Andean foxes (Lycalopex culpaeus), and 90 grey foxes (L. griseus) were obtained from six different bioclimatic regions throughout Chile.Para acceder a la videoconferencia completa, hacer clic en "Enlace externo".Sociedad Latinoamericana de Ecología de Vectore

Analysis of climate and extrinsic incubation of Dirofilaria immitis in southern South America

Dirofilariosis, caused by Dirofilaria immitis and D. repens, is spreading in several geographic regions. The development of infective larvae in the mosquito vector (extrinsic incubation) needs an accumulated total of 130 degree-days above the 14 ºC threshold, normally expressed as heartworm development units (HDUs). Based on this information, temperature- based models have been developed and applied to evaluate the distribution and spread of Dirofilaria infections in various countries and continents. Despite the confirmed presence of D. immitis in most South American countries, the available information about its epidemiology remains scarce. We analysed the temporal and spatial extrinsic incubation of this parasite in Argentina, Chile and Uruguay, taking into account daily temperatures from 49 meteorological stations during a 30-year period (1982-2012). The theoretically possible number of D. immitis generations was calculated based on the number of meteorological stations that reached the 130-HDUs threshold. The resulting information was spatially interpolated using the inverse weighted distance (IWD) model to produce thematic maps. The model shows that 41 of the meteorological stations reach the threshold needed and that D. immitis transmission is markedly seasonal with a peak in late spring (December), stable during summer (January to March) and declining in the autumn (April and May). Suitable temperatures exist in Uruguay and most of Argentina, whereas D. immitis transmission in Chile is only possible in the north and in the central inlands. The results suggest that the climatic impact on D. immitis transmission must have been minimal in the countries investigated since the annual meteorological records did not change much during the 30-year period analysed

Antimicrobial resistance genes in Andean foxes inhabiting anthropized landscapes in central Chile

6 Pág.Antimicrobial resistance (AMR) is considered an emerging public health problem. Greater AMR development rate is associated with "antibiotic-using" environments. Wildlife thriving in anthropized landscapes could be good indicators of the burden of AMR and antibiotic resistance genes (ARGs) in these areas. The aim of this study was to determine the presence and load of ARGs in fecal swabs of wild Andean foxes (Lycalopex culpaeus) from anthropized landscapes of central Chile. DNA was extracted from samples of 72 foxes; 22 ARGs encoding resistance against 8 antibiotic groups were evaluated using qPCR. Eighteen of the 22 ARGs were found and tet(Q) (65.3%; 15/72 of the samples) was the most common gene detected. Almost half of the foxes presented a 'multiresistant microbiome' (i.e. at least three ARG encoding resistance to different groups of antimicrobials). Prevalence of tet(Q) was higher in the cold-humid season than in the warm-dry season, but not for other genes. Up to 15 and 13 ARGs were detected in the fecal samples from two additional foxes that were kept 6 and 11 days, respectively, in a clinical environment (Wildlife Rescue Center) and received antibiotic treatment. Some of the ARGs detected (e.g. mecA and blaCTX-M) in the present study are of particular concern from the public health perspective. Wild foxes seem to be good sentinels for ARG environmental burden in highly anthropized environments of central Chile.This study was funded by FONDECYT 1161593 and “Fondo para la iniciación a la investigación UNAB”. This study was approved by the authorities in bioethics from the Universidad Andres Bello under authorization 08/2016. Capture permits were granted by the Servicio Agrícola y Ganadero (Resolutions n°: 1878-2016, 4469-2016, 3379-2017, 3380-2017, 8153-2017, 2655/2018, 4454/2018).Peer reviewe