ABSTRACT: Our goal was to assess whether free-ranging foxes have been exposed to canine distemper virus (CDV) in the Araucanía region in Chile. The study was conducted at three sites in rural areas where free-ranging foxes were trapped and bled from 2009 to 2012. We sampled two species of foxes: the culpeo (Lycalopex culpaeus) (n=13) and the chilla (Lycalopex griseus) (n=14). A serum virus neutralization assay was used to detect the presence and magnitude of functional systemic antibodies to CDV. Overall, CDV seroprevalence in culpeo and chilla foxes was 7.7 and 21.4%, respectively. Exposure to CDV did not differ among the sites. Despite the relatively low seroprevalence found in free-ranging foxes, the presence of CDV-seropositive dogs previously reported in rural sites nearby, suggests a potential risk of pathogen spill over from domestic dogs to foxes in the area.

Abstract Gastrointestinal parasites are well-documented in small mammals from north-central Chile, but little is known about endoparasites of rodents in southern Chile. A survey was conducted between January and February 2018 to evaluate gastrointestinal parasites and risk factors of wild rodents that live in rural areas in Northern Chiloé Island, Chile. A total of 174 fecal samples from rodents of six native and one introduced species were collected and examined using the Mini-FLOTAC method. Also, 41 individuals of four native wild rodent species were examined furtherly to determinate adult parasites from gastrointestinal tracts. The overall prevalence of endoparasites was 89.65% (156). Helminth egg types included: Rodentolepis spp., Capillariidae, Trichuris sp., Syphacia sp., oxyurid-type eggs, Strongyloides sp., Spirurid-type eggs, Strongilid-type eggs, Moniliformis sp., and an unidentified nematode egg and larvae. Protozoa comprised coccidia, amoeba, and unidentified cysts. From necropsies, adult parasites involved Syphacia sp. Trichuris sp., Protospirura sp. and Physaloptera sp. In Abrothrix olivacea, individuals with low-body-mass index exhibited reduced infection probability for Spirurid-type and Strongilid-type eggs. Some parasites in this study may affect human health. In rural settings where environmental conditions are changing, more research should be undertaken to understand parasitic infections in wildlife and implications for public health and conservation.

Resumo Parasitos gastrointestinais são bem documentados em pequenos mamíferos do centro-norte do Chile, mas pouco conhecido sobre endoparasitos de roedores no sul do Chile. Uma pesquisa foi realizada entre janeiro e fevereiro de 2018, avaliando parasitas gastrointestinais e fatores de risco de roedores selvagens vivendo em áreas rurais no norte da Ilha de Chiloé, Chile. Um total de 174 amostras fecais de roedores de seis espécies nativas e uma introduzida foi coletado e examinado pelo método Mini-FLOTAC. Ademais, 41 indivíduos de quatro espécies nativas de roedores selvagens foram examinados para determinar parasitas adultos do trato gastrointestinal. A prevalência geral de endoparasitos foi de 89,65% (156). Os tipos de ovos de helmintos incluíram: Rodentolepis spp., Capillariidae, Trichuris sp., Syphacia sp.; dos tipos Oxyurideos, Strongyloides sp., dos tipos Spirurideos e Estrongilideos, Moniliformis sp.; e um ovo e larvas de nematoides não identificados. Os protozoários compreendiam coccídios, amebas e cistos não identificados. Nas necropsias, os parasitos adultos envolveram Syphacia sp. Trichuris sp., Protospirura sp. e Physaloptera sp. Em Abrothrix olivacea, indivíduos com baixo índice de massa corporal apresentaram probabilidade de infecção reduzida para ovos Spirurideos e Estrongilideos. Alguns parasitos, neste estudo, podem afetar a saúde humana. Em ambientes rurais, onde as condições ambientais mudam, mais pesquisas são necessárias para entender as infecções parasitárias na vida selvagem e as implicações para a saúde pública e conservação.

Abstract The tick Amblyomma tigrinum inhabits areas with diverse climatic conditions, with adult stages parasitizing wild canids, such as chilla (Lycalopex griseus) and culpeo (Lycalopex culpaeus) foxes. We described the infestation loads in wild foxes captured at three sites (periurban, rural and wild) through an anthropization gradient in north-central Chile. We tested whether local-scale environmental and/or individual host factors can predict tick abundance by using negative binomial models. During 2018-2020 (spring and summer), we captured 116 foxes (44 chillas and 72 culpeos), and 102 of them were infested with ticks (87.9%, CI=80.6-93.2%). We collected 996 A. tigrinum adult ticks, estimating a total mean abundance of 8.6±0.8 ticks/host. Periurban and rural foxes harbored greater tick loads than foxes from the wild site (2.34 and 1.71 greater, respectively) while tick abundance in summer decreased by up to 57% compared to spring. Tempered, more humid climate conditions of the periurban site could favor the development and survival of adults A. tigrinum; and ticks may have adopted a quiescent stage or similar survival mechanisms to cope with summer temperature increases related to the ongoing megadrought. Further studies are warranted to understand the underlying factors determining the life cycle of A. tigrinum at larger spatiotemporal scales.

Resumo Amblyomma tigrinum habita em áreas com diversas condições climáticas, com estágios adultos, geralmente, parasitando canídeos silvestres, como chilla (Lycalopex griseus) e culpeo (Lycalopex culpaeus). Neste trabalho, são descritas as cargas de infestação de A. tigrinum em raposas silvestres, capturadas em três locais (periurbano, rural e silvestre) no centro-norte do Chile. Foi testado se os fatores ambientais e/ou individuais do hospedeiro, em escala local, podem prever a abundância de carrapatos, usando-se modelos binomiais negativos. Durante 2018-2020 (primavera e verão), foram capturadas 116 raposas (44 chillas e 72 culpeos), e 102 delas estavam infestadas por carrapatos (87,9%, IC=80,6-93,2%). Foram coletados 996 carrapatos adultos de A. tigrinum, estimando-se uma abundância média total de 8,6±0,8 carrapatos/hospedeiro. As raposas periurbanas e rurais abrigaram cargas de carrapatos maiores do que as raposas do local silvestre (2,34 e 1,71 maior, respectivamente), enquanto a abundância de carrapatos, no verão, diminuiu até 57% em comparação com a primavera. As condições climáticas temperadas e mais úmidas do sítio periurbano podem favorecer o desenvolvimento e a sobrevivência dos adultos de A. tigrinum; e os carrapatos podem ter adotado um estágio quiescente ou mecanismos de sobrevivência semelhantes, para lidar com os aumentos de temperatura no verão, relacionados à mega seca em andamento.

ABSTRACT Adult individuals of Amblyomma tigrinum were collected for the first time from a Molina’s hog-nosed skunk (Conepatus chinga), captured in a rural area of north-central Chile, which were described and identified morphologically. There are scarce studies that address the role of the skunk as ectoparasite host; however, the great plasticity of A. tigrinum to inhabit different environments and its strict to moderate specificity for Carnivora order suggest this mephitid as a potentially suitable host for this tick species.

RESUMEN Se colectan por primera vez individuos adultos de Amblyomma tigrinum en un chingue (Conepatus chinga), capturado en área rural del norte-centro de Chile, los cuales fueron descritos e identificados morfológicamente. Existen escasos estudios que aborden el rol del chingue como hospedador de ectoparásitos; sin embargo, la gran plasticidad de A. tigrinum para habitar diferentes ambientes y su especificidad estricta a moderada por el orden Carnivora sugieren a este mefítido como un hospedador potencialmente adecuado para esta especie de garrapata.

Two species of grey foxes are recognized in the Southern Cone of America: Lycalopex griseus, and L. gymnocercus, which were traditionally separated by size and some cranial differences. Morphometric analyses of the skull showed that both species could be the same and that they show clinal variation, while DNA studies based on one mitochondrial marker suggested that they belong to different species. Our objective is to evaluate the systematic status of these foxes using three mitochondrial markers (cytochrome B, cytochrome oxidase I, and control region), and a large sample covering a wide geographic range. The results indicate that there are two clades, that are not sister taxa, a finding that is more congruent with the hypothesis of two species, but their geographic distribution is not coincident with the accepted distribution of L. griseus and L. gymnocercus. Consequently, the distribution of L. griseus is extended eastern including north and center of Argentina, towards the west and south of the Paraná, Paraguay and Río de la Plata rivers. On the other hand, the clade that probably represents L. gymnocercus is restricted to the east of those rivers, except for a few specimens collected in Santa Fe, close to the Paraná river. However, an analysis of a wider sample using nuclear DNA is needed to confirm the taxonomic identity of these species of grey foxes.

Dos especies de zorros grises se reconocen en el Cono Sur de América: Lycalopex griseus y L. gymnocercus, que tradicionalmente estaban separadas por tamaño y algunas diferencias craneales. Análisis morfométricos del cráneo mostraron que estas especies podrían ser una sola que muestra variación clinal, mientras que estudios de ADN basados en un marcador mitocondrial sugirieron que pertenecen a especies diferentes. Nuestro objetivo es evaluar el estado sistemático de estos zorros utilizando tres marcadores mitocondriales (citocromo B, citocromo oxidasa I y región control) y una muestra grande que cubre un amplio rango geográfico. Los resultados indican que hay dos clados, que no son taxones hermanos, un hallazgo que es más congruente con la hipótesis de dos especies, pero su distribución geográfica no es coincidente con la distribución aceptada de L.  griseus y L.  gymnocercus. Consecuentemente, la distribución de L. griseus se extiende hacia el este, incluyendo el norte y centro de la Argentina, hacia el este y el sur de los ríos Paraná, Paraguay y Río de la Plata. Por el otro lado, el clado que probablemente representa a L. gymnocercus está restringido hacia el este de esos ríos, excepto por algunos especímenes colectados en Santa Fe, cerca del río Paraná. Sin embargo, se necesita un análisis de una muestra más amplia que utilice ADN nuclear para confirmar la identidad taxonómica de estas especies de zorros grises.

ABSTRACT We aimed to identify faeces belonging to either Darwin’s fox (Lycalopex fulvipes) or kodkod (Leopardus guigna) by using molecular genetic techniques, and to describe and compare the gastrointestinal parasites harbored by both carnivores in Chiloé Island. We found that 60% (25/42) and 88% (28/32) of faeces of Darwin’s fox and kodkod had parasite eggs. This study provided the first record of Aspiculuris sp. and trematodes in Darwin’s fox and Aspiculuris sp., Trichuris sp., Capillaria sp., Isospora sp. and trematodes in kodkod, which may correspond to either prey- or host-originated parasites.

RESUMEN Nuestro objetivo fue identificar heces pertenecientes a zorro de Darwin (Lycalopex fulvipes) o güiña (Leopardus guigna) utilizando técnicas de genética molecular, y describir y comparar los parásitos gastrointestinales albergados por ambos carnívoros en la isla de Chiloé. Encontramos que 60% (25/42) y 88% (28/32) de heces de zorro de Darwin y güiña tuvo huevos de parásito. Este estudio entregó el primer registro de Aspiculuris sp. y tremátodos en zorro de Darwin y Aspiculuris sp., Trichuris sp., Capillaria sp., Isospora sp. y tremátodos en güiña, que podrían corresponder a parásitos de presas u hospederos.

Scrub typhus, caused by Orientia tsutsugamushi and transmitted by larvae of trombiculid mites, is an endemic rickettsiosis in the Asia Pacific region. After the first identification of a case in Chile in 2006, more than 30 cases have been diagnosed by our group since 2015. Cases were detected predominantly during the Chilean summer months. Patients presented with fever, rash, and a typical eschar at the inoculation site; other frequent findings were intense headache, night sweats, increased laboratory markers of inflammation and transaminases. The vast majority of cases have been diagnosed in southern Chile (mainly Chiloé Island), although recently some cases were also identified in the central Metropolitan Region in patients returning from trips to southern Chile. Physicians attending Chilean patients should be aware of this emerging infection to be able to initiate empirical therapy with doxycycline. The confirmation of cases by the diagnostic methods available in Chile will contribute to a better understanding of the epidemiological and clinical relevance of this emerging infection in South America.

Resumen El tifus de los matorrales, causado por Orientia tsutsugamushi y transmitido por larvas de ácaros trombicúlideos de roedores silvestres es una rickettsiosis endémica en el Asia Pacífico. Luego del primer caso identificado en Chile en el año 2006, nuestro grupo ha identificado más de 30 casos a partir del año 2015. Los casos se han presentado con un marcado predominio en meses de verano, y su presentación clínica incluye fiebre, exantema y una mancha negra en el sitio de inoculación. Otros hallazgos frecuentes han sido cefalea intensa, sudoración nocturna, aumento de PCR, VHS y transaminasas hepáticas. La gran mayoría de los pacientes se han diagnosticado en el sur de Chile (principalmente la isla de Chiloé), pero recientemente también se han presentado casos en la Región Metropolitana, en personas volviendo de viajes al sur de Chile. Los médicos clínicos deben estar informados de esta enfermedad emergente en el país, de modo de sospecharla e iniciar terapia empírica con doxiciclina. La confirmación de estos casos con los métodos diagnósticos disponibles en Chile contribuirá a una mejor comprensión del rango epidemiológico y la relevancia clínica de esta infección nueva en el país.

Background: The Coquimbo Region in Chile has the highest incidence of hydatidosis in central and northern Chile. Aim: To analyze the incidence of human cystic echinococcosis (CE) in the Coquimbo Region between 2008 and 2012. Material and Methods: Official records of reported cases were analyzed. The association of the location, age and sex with the presence/absence of CE was analyzed by means of logistic regressions. The incidence was reported as cases per 100,000 inhabitants. Results: The mean annual incidence was 2.6 cases per 100,000 inhabitants, which ranged from 3.1 (2010) to 1.9 (2012) cases. The districts with higher incidence were Punitaqui (21.2 cases), Paihuano (9 cases), Rio Hurtado (8 cases), Canela (8.1 cases), Monte Patria (7.9 cases), Vicuña (6.9 cases) and Combarbalá (6.9 cases). The incidence in these locations was significantly higher than elsewhere in the region. Males had a significantly higher incidence than females (3.3 and 1.8 respectively). Incidence increased significantly with age, notably increasing after 45 years of age. Conclusions: Rural locations had the highest incidences of CE in the Coquimbo Region. The disease was reported more commonly in adults and mainly in men.

Objective: To determine the prevalence of hydatidosis in humans and livestock in the Los Ríos region during the years 1999-2009. Methods: A retrospective survey of all discharge records of patients undergoing removal of cysts produced by Echinococcus granulosus during the period 1999-2009 in the Hospital Clinico Regional of Valdivia was conducted. With the information provided incidence rate, mortality rate and fatality rate were calculated. Additionally, with the aim of determining prevalence of hydatidosis in livestock (i.e. cattle, sheep and pigs) official records of slaughtered animals for the same period from the Ministry of Health of Los Ríos region were searched. Results: During the ten-year period 238 new human cases were recorded, the average incidence rate for the period was 6.1 per 100,000 inhabitants, the mortality rate was 0.1 per 100,000 inhabitants, and the fatality rate was 1.3%. The most affected class group was the 15-64 years old with a 70% of cases. The districts more affected were Valdivia and Río Bueno. Most cases (54%) were from patients from rural areas, while the occupation more affected was housekeeping (29%). The liver (56%) and lungs (33%) were the localization where cysts were most frequently found. On 55% of cases, patients did not show any complication; meanwhile, infected cyst (11%) and unspecified complicated (8%) were the more frequent complication. Overall, 89% of cases recovered totally after surgery. Finally, the average in patient time was 14.7 bed-days. Prevalence of hydatidosis in livestock was 23% in cattle, 23% in sheep and 12% in pigs. The highest prevalence was found in slaughter houses in the districts of Panguipulli and San José de la Mariquina. Discussion: Human and animal hydatidosis is highly prevalent in humans and livestock in Los Ríos region compared to national and international records. Further research is recommended to assess risk factors for human infection and improving record-keeping and trazability of slaughtered animals to implement control measures at the farm level to help to stop the life cycle of the parasite and thus reduce human infections.

Objetivos y Métodos: Para determinar la prevalencia de hidatidosis humana y animal en la Región de Los Ríos durante los años 1999-2009, se realizó un análisis retrospectivo de las fichas clínicas de operados por esta enfermedad en el Hospital Clínico Regional de Valdivia. Se cuantificó morbilidad, mortalidad y letalidad y se determinaron algunas características epidemiológicas de la enfermedad. Adicionalmente, para determinar la prevalencia de equinococosis quística en el ganado, se analizaron los registros oficiales sobre la frecuencia de presentación de quistes en vísceras decomisadas en bovinos, ovinos y porcinos faenados en mataderos de la región durante el mismo período, obtenidos de la SEREMI de Salud. Resultados: Se registraron 238 casos nuevos en humanos con una tasa de incidencia promedio de 6,1 por 100 mil habs., una tasa de mortalidad de 0,1 por 100 mil habs. y una tasa de letalidad de 1,3%. En total, 53% de los casos fueron hombres y 47% mujeres. El grupo de edad entre 15 y 64 años fue el más afectado (70% del total). Las comunas con mayor número de casos fueron Valdivia y Río Bueno. Se detectaron más casos (54%) en zonas rurales que urbanas (46%). Por otro lado, la ocupación más afectada correspondió a dueñas de casa. La localización más frecuente fue hepática exclusiva (56%). Un 55% de los pacientes no mostró complicación de los quistes tratados. Después de la operación, 89% de los casos se recuperó totalmente, mientras que el período de hospitalización promedio fue de 14,7 días-cama por paciente. La prevalencia de equinococosis en ganado fue de 23% en bovinos, 23% en ovinos y 12% en porcinos. Las mayores prevalencias se reportaron en mataderos de Panguipulli y San José de la Mariquina. Discusión: La hidatidosis humana y animal son altamente prevalentes en la Región de Los Ríos comparadas con el resto del país y otras naciones. Se recomienda la realización de estudios avanzados para determinar factores de riesgo para la infección en humanos y realizar mejoras en la trazabilidad de los animales sacrificados para implementar medidas de control a nivel del predio y de esa forma cortar el ciclo del parásito y ayudar a reducir la infección en humanos.

Introduction: Candidatus 'Rickettsia andeanae' is recently recognized specie, with no attributed pathogenic role so far. It has been reported in Amblyomma ticks from Peru, USA and Argentina, and recently in Chile, in one specimen of Amblyomma triste from a rural locality in Arica. Objective: To determine the presence of rickettsial agents in ticks from domestic dogs from two Chilean regions. Methods: A transversal descriptive study in Coquimbo and La Araucanía regions, consisted in households sampling in the cities of Coquimbo and Aingol and nearby rural localities, in spring-summer 2011-2012. One dog per house was examined and ticks were collected when present; after taxonomic identification, gltA and ompA genes were amplified and sequenced. Results: 462 dogs were examined, 255 had ticks (55%). In the cities just Rhipicephalus sanguineus was found; in rural localities also Amblyomma tigrinum. Obtained sequences in 12 specimens from A. tigrinum corresponded to Candidatus 'Rickettsia andeanae'. Conclusions: We documented the presence of R. andeanae in two distant Chilean regions, which is added to its recently finding in the Northern extreme of the country. This new rickettsial agent limits to Amblyomma ticks and rural areas, as it was reported in other American countries and corresponds with this tick habitat.

Introducción: Candidatus 'Rickettsia andeanae', especie de reciente reconocimiento y rol patógeno no precisado, ha sido identificada en garrapatas del género Amblyomma en Perú, E.U.A. y AArgentina y recientemente en Chile, en un espécimen de Amblyomma triste de un sector rural de Arica. Objetivo: Determinar presencia de agentes rickettsiales en garrapatas de perros domésticos de dos regiones de Chile. Métodos: Estudio transversal, descriptivo, en las regiones de Coquimbo y La Araucanía, con muestreo domiciliario en las ciudades de Coquimbo y AAngol y localidades rurales cercanas, en primavera-verano 2011-2012. Se examinó un perro por vivienda, recolectando garrapatas si estaban presentes; luego de su identificación taxonómica fueron sometidas a amplificación y secuenciación de los genes gltA y ompA. Resultados: Se examinaron 462 perros, 255 tenían garrapatas (55%). En las ciudades se encontró exclusivamente Rhipicephalus sanguineus; en las localidades rurales además Amblyomma tigrinum. Las secuencias obtenidas en 12 especímenes de A. tigrinum correspondieron a Candidatus 'Rickettsia andeanae'. Conclusiones: Se documenta presencia de R. andeanae en dos regiones distantes de Chile, lo que se suma a su reciente hallazgo en el extremo norte del país. Este nuevo agente rickettsial se limita a garrapatas del género Amblyomma y a zonas rurales, lo que concuerda con lo documentado en otros países y con el hábitat de esta garrapata.