Keyword: zoonosis

Parasites of Amazonian manatees in a rescue center in Loreto, Peru

, , , , ,

The Amazonian manatee, Trichechus inunguis, is the only sirenian present in freshwater rivers and is classiffied as a “vulnerable” species according to the IUCN. Individuals rescued from the pet trade in Peruvian Amazonia are brought to the Centro de Rescate Amazónico (CREA), rehabilitated, and released to their natural environment. Parasitic diseases can cause serious problems in the rehabilitation and release of rescued animals. In this study, entero- and hemoparasites of ten manatees in the rehabilitation facilities of the CREA in Loreto, Peru were studied. Parasites were searched in fecal and blood samples using the Willis method, Kinyoun stain, and Giemsa stain. Six species of protozoan parasites from the genera Eimeria, cf. Cyclospora, cf. Cryptosporidium and cf. Entamoeba were observed. Helminths (six species of nematodes and one trematode) were recorded. Hemoparasites were not detected. Our results give insights into the presence of parasites in captive Amazonian manatees and should be taken into account in future rehabilitation and reintroduction processes.

Parásitos del manatí amazónico en un centro de rescate en Loreto, Perú. El manatí amazónico, Trichechus inunguis, es el único sirenio presente en agua dulce y está clasificado como especie «vulnerable» según la UICN. Los manatíes rescatados del tráfico ilegal en la Amazonia peruana son llevados al Centro de Rescate Amazónico (CREA), donde se rehabilitan y reintroducen a su medio natural. Las enfermedades parasitarias causan serios problemas en la rehabilitación y liberación de los animales rescatados. Se estudiaron enteroparásitos y hemoparásitos de diez manatíes en las instalaciones de rehabilitación del CREA en Loreto, Perú. Se buscaron parásitos desde muestras fecales y de sangre mediante el método de Willis, la tinción de Kinyoun y la tinción de Giemsa. Se detectaron seis especies de parásitos protozoos de los géneros Eimeria, cf. Cyclospora, cf. Cryptosporidium y cf. Entamoeba. Se registraron helmintos (seis especies de nematodos y un trematodo). No se hallaron hemoparásitos. Nuestros resultados aportan información sobre la presencia de parásitos en los manatíes amazónicos en cautiverio y deberían tenerse en cuenta en futuros procesos de rehabilitación y reintroducción.

Graphical abstract for the article “Parasites of Amazonian manatees in a rescue center in Loreto, Peru” (Ruiz P. et al., 2024)

Natural Trichinella spiralis infection in wild and domestic vertebrates in a trichinellosis endemic area from Argentina

, , , ,

Wildlife is a potential source for emerging and re-emerging zoonotic diseases. Trichinella spiralis is the major etiological agent that causes Trichinella spp. infection in humans and domestic pigs, but other Trichinella species are also involved. Pigs are the most important source of Trichinella spp. infection worldwide, being their outdoor breeding, waste feeding, their exposure to wildlife and their carcasses, the documented risk factors for pig production, food security, and health. Early Trichinella spp. detection and the study of their reservoir’s competence are needed to prevent and control Trichinella spp. infection. The aims of this study were to analyze the occurrence of Trichinella spp. infection in synanthropic and non-synanthropic wild and domestic animals in rural areas, and compare Trichinella spp. infection in synanthropic and non-synanthropic wild small mammals on intensive and extensive piggeries. This is a two-year study in an endemic area of the disease. To evaluate parasite infection, we included samples from animals captured in 18 intensive and extensive piggeries and from road-killed vertebrates collected lengthwise 882 km within 13 counties along eight consecutive seasons. Trichinella spp. infection association to small mammals’ infestation levels and community composition and structure was analyzed. From a total of 697 wild and domestic animals analyzed, infected Rattus norvegicus and Didelphis albiventris individuals were found in two extensive piggeries. The parasite was not found outside piggeries. Infections were identified as T. spiralis by a Nested-Multiplex PCR. These findings showed some evidence that supports the idea that extensive farming has a higher risk of transmission of T. spiralis than intensive farming.

Infección natural de Trichinella spiralis en vertebrados silvestres y domésticos en un área endémica de triquinosis de Argentina. La fauna silvestre es una potencial fuente de enfermedades zoonóticas emergentes y reemergentes. Trichinella spiralis es el principal agente etiológico que causa la infección de Trichinella spp. en humanos y cerdos, pero también otras especies de Trichinella están involucradas. Los cerdos son la fuente más importante de infección por Trichinella spp. a nivel mundial, mientras que su cría al aire libre, la alimentación con desechos, su exposición a la fauna silvestre y sus cadáveres son los factores de riesgo conocidos para la producción porcina, la seguridad alimentaria y la salud. La detección temprana de Trichinella spp. y el estudio de la competencia de sus reservorios son necesarios para prevenir y controlar la triquinelosis. Los objetivos de este estudio fueron evaluar la ocurrencia de infección de Trichinella spp. en animales silvestres sinantrópicos y no sinantrópicos, y en animales domésticos en un área rural, y comparar la ocurrencia de infección de Trichinella spp. en pequeños mamíferos sinantrópicos y no sinantrópicos en granjas porcinas intensivas y extensivas. Este estudio de dos años se realizó en un área endémica de la enfermedad. Para evaluar la infección parasitaria, incluimos muestras de animales capturados en 18 granjas porcinas intensivas y extensivas y de vertebrados atropellados recolectados a lo largo de 882 km en 13 departamentos durante ocho estaciones consecutivas. Se analizó la asociación de la infección por Trichinella spp. con los niveles de infestación de pequeños mamíferos y la composición y estructura de la comunidad. De un total de 697 animales silvestres y domésticos analizados, se encontraron individuos infectados de Rattus norvegicus y Didelphis albiventris en dos criaderos extensivos. El parásito no se encontró fuera de las granjas porcinas. Mediante una PCR Nested-Multiplex las infecciones se identificaron como T. spiralis. Encontramos alguna evidencia que apoya la idea de que las granjas de cría extensiva de cerdos tienen un mayor riesgo para la transmisión de T. spiralis que la cría intensiva.

Graphical abstract for the article “Natural Trichinella spiralis infection in wild and domestic vertebrates in a trichinellosis endemic area from Argentina” (Montes de Oca et al., 2024)

Marsh deer (Blastocerus dichotomus) as a new host for Leptospira borgpetersenii in Argentina

, , , , , , ,

Leptospirosis is a worldwide re-emerging zoonosis caused by bacteria of the genus Leptospira. All mammals are potentially susceptible to pathogenic Leptospira, while certain species can act as reservoirs of the bacterium, whose main route of transmission is water. The marsh deer (Blastocerus dichotomus) is a wetland-dependent native cervid distributed in the Paraná-Paraguay River and influence areas. During the last decades, its populations have undergone mortality episodes of multifactorial origin. Since wetlands constitute favorable scenarios for the transmission of Leptospira, we investigated the occurrence of this agent in 12 marsh deer from the subpopulation of the Paraná Delta in Argentina, categorized as “Endangered”. DNA was extracted from urine and/or kidney samples, and characterization was performed at the species level by PCR amplification of the 16S rRNA gene. An aliquot of urine and serial dilutions of kidney macerates were seeded in a semisolid EMJH medium spiked with 5-Flurouracil, and isolation was achieved in a kidney sample. Leptospira borgpetersenii was detected in two samples (one from urine and one from kidney), constituting the first report in marsh deer. Our findings add a new species as the host of L. borgpetersenii, whose circulation in wildlife has been little studied in the region. Further studies are needed to determine the transmission patterns of this bacterium in wildlife, evaluate its pathogenicity in marsh deer and other wild species, and explore the existence of reservoirs in natural areas.

El ciervo de los pantanos (Blastocerus dichotomus) como un nuevo hospedador de Leptospira borgpetersenii en Argentina. La leptospirosis es una zoonosis reemergente extendida a nivel mundial causada por bacterias del género Leptospira. Todos los mamíferos son potencialmente susceptibles a las variantes patogénicas de Leptospira, mientras que determinadas especies pueden actuar como reservorios de la bacteria, cuya principal vía de transmisión es el agua. El ciervo de los pantanos (Blastocerus dichotomus) es un cérvido nativo dependiente de humedales que se distribuye en el corredor fluvial Paraná-Paraguay y áreas de influencia. Durante las últimas décadas, sus poblaciones atravesaron episodios de mortalidad de origen multifactorial. Dado que los humedales constituyen escenarios propicios para la transmisión de Leptospira, hemos investigado la ocurrencia de este agente en 12 ciervos de los pantanos de la subpoblación del Delta del Paraná en Argentina, categorizada como «En Peligro». Se extrajo ADN de muestras de orina o riñón, y se realizó la caracterización a nivel de especie mediante amplificación por PCR del gen 16S rARN. Una alícuota de orina y diluciones seriadas de macerados de los riñones se sembraron en un medio semisólido EMJH adicionado con 5-Flurouracilo, y se logró el aislamiento en una muestra de riñón. Se detectó Leptospira borgpetersenii en dos muestras (una de orina y otra de riñón), lo que constituye el primer informe de esta especie en ciervo de los pantanos. Nuestros hallazgos añaden una nueva especie como hospedador de L. borgpetersenii, cuya circulación en la fauna silvestre ha sido poco estudiada en la región. Se necesitan nuevos estudios para determinar los patrones de transmisión de esta bacteria en la fauna silvestre, evaluar su patogenicidad en el ciervo de los pantanos y en otras especies silvestres, y explorar la existencia de reservorios en áreas naturales.

Graphical abstract for the article “Marsh deer (Blastocerus dichotomus) as a new host for Leptospira borgpetersenii in Argentina” (Orozco et al., 2024)

Evidences of non-lethal rabies virus exposure in free-ranging wild carnivores from Brazilian Pampa

, , , , , , , , , , , ,

Rabies virus (RABV) may infect wildlife, domestic mammals, and humans worldwide, and outbreaks have been associated with population declines of wild carnivores. Although RABV infection has been considered almost invariably fatal, there has been growing evidence of non-lethal RABV exposure in wildlife. The aim of this study is to investigate the occurrence of RABV antibodies, as evidence of non-lethal exposure to the virus in free-living wild canids and felids from the Brazilian Pampa. Animals were live-trapped in three protected and two unprotected areas in Southern Brazil, and the presence of antibodies against RABV was verified by the RFFIT test. A total of 98 specimens without clinical signs of disease were live-trapped: 35 Cerdocyon thous, 23 Lycalopex gymnocercus, 29 Leopardus geoffroyi, 11 Leopardus wiedii. Thirteen out of 98 wild carnivores were considered seropositive to RABV: five C. thous, one L. gymnocercus, five L. geoffroyi, and two L. wiedii. All five localities where animals were sampled had at least one seropositive individual. The results support previous conclusions regarding the possible involvement of C. thous in the rabies ecology and expand the findings of RABV-seropositivity in free-living wildlife, representing the first record for the following species: L. gymnocercus, L. geoffroyi, and L. wiedii. Our findings also suggest that RABV circulation and non-lethal exposure in Neotropical wild carnivores may be more common than previously assumed. Furthermore, rabies and its sylvatic cycle should be taken into account in any conservation effort for wild carnivores.

Evidências de exposição não-letal ao vírus da raiva em carnívoros silvestres de vida livre no Pampa brasileiro. O vírus da Raiva (RABV) pode infectar mamíferos silvestres, domésticos e humanos em todo o mundo, e surtos têm sido associados com declínios populacionais em carnívoros silvestres. Apesar da infecção pelo RABV ser considerada invariavelmente fatal, há evidências crescentes de exposição não-letal em animais silvestres. O objetivo deste trabalho é investigar a ocorrência de anticorpos contra RABV, como evidência de exposição não-letal ao vírus em canídeos e felídeos de vida livre no Pampa brasileiro. Os animais foram capturados em três áreas de preservação e duas áreas não-protegidas do Sul do Brasil, e a presença de anticorpos contra RABV foi verificada por RFFIT. Um total de 98 espécimes sem sinais de doença foram capturados: 35 Cerdocyon thous, 23 Lycalopex gymnocercus, 29 Leopardus geoffroyi e 11 Leopardus wiedii. Treze dos 98 carnívoros silvestres foram considerados soropositivos para RABV: cinco C. thous, um L. gymnocercus, cinco L. geoffroyi, e dois L. wiedii. Todas as cinco localidades onde os animais foram amostrados apresentaram ao menos um indivíduo soropositivo. Os resultados corroboram conclusões anteriores sobre o possível envolvimento de C. thous na ecologia da raiva, e expandem os achados de soropositividade para RABV em animais silvestres, representando o primeiro registro para as seguintes espécies: L. gymnocercus, L. geoffroyi e L. wiedii. Nossos resultados também sugerem que a circulação do RABV e a exposição não-letal em carnívoros silvestres neotropicais pode ser mais comum do que previamente assumido. Outrossim, a raiva e seu ciclo silvestre devem ser levados em consideração em qualquer esforço de conservação de carnívoros silvestres.

Graphical abstract for the article “Evidences of non-lethal rabies virus exposure in free-ranging wild carnivores from Brazilian Pampa” (Padilha et al., 2024)

Felinos neotropicais como hospedeiros de agentes zoonóticos no Brasil

,

Os mamíferos apresentam papel central no ciclo de várias zoonoses e o estudo de sua prevalência e distribuição é extremamente importante para prevenir surtos e criar profilaxias. As espécies de felinos silvestres têm cada vez mais contato com os humanos, expondo-os a possíveis transbordamento ou compartilhamento de vários patógenos e participando do ciclo de várias zoonoses. Nosso objetivo foi investigar a participação das espécies de felinos silvestres do Brasil em ciclos zoonóticos, a partir de dados secundários. Foram encontrados registros de 19 zoonoses para 10 espécies de felinos silvestres, incluindo duas causadas por vírus, cinco por nematoides, quatro por protozoários e oito por bactérias. A zoonose com maior prevalência causada por vírus foi a raiva, por protozoários foi a toxoplasmose, por bactérias destacam-se brucelose e leptospirose, enquanto que por nematoides destaca-se a ancilostomose e toxocaríase. As espécies Leopardus pardalis, Leopardus tigrinus, Panthera onca e Puma concolor apresentaram maior número de registros de patógenos e distribuição mais ampla dos registros pelas regiões brasileiras. Os registros desses patógenos ocorreram principalmente nas regiões Centro-Oeste e Sudeste do Brasil. Observa-se o papel dos membros dessa família como reservatórios de agentes de várias zoonoses letais, embora a leptospirose apresente registro de diferentes sorovares, incluindo alguns não patogênicos ao homem. Esses resultados trazem à luz a importância da preservação e manutenção dos habitats naturais dessas espécies como medida de saúde pública, a fim de prevenir a proliferação dessas zoonoses, tanto para os humanos quanto para os animais. A preservação dos ambientes naturais dos felinos poderia minimizar possíveis trocas de patógenos entre essas espécies e os animais domésticos e, consequentemente, com os humanos, além de diminuir a probabilidade de contato direto desses com os felinos.

Neotropical Felidae as hosts of zoonotic agents in Brazil. Mammals play a central role in the cycle of several zoonoses; the study of their prevalence and distribution is extremely important to prevent outbreaks and create prophylaxis mechanisms. Wild feline species have been increasingly in contact with humans, exposing them to possible overflow or sharing of various pathogens and participating in the cycle of numerous zoonoses. Our objective was to investigate the participation of Brazilian feline species in zoonotic cycles, through secondary data analysis. We found records of 19 zoonoses for 10 feline species, including two caused by viruses, five by nematodes, four by protozoa, and eight by bacteria. The zoonosis with highest prevalence caused by viruses was rabies, by protozoa was toxoplasmosis, by bacteria were brucellosis and leptospirosis; while by nematodes were hookworm and toxocariasis. The species Leopardus pardalis, Leopardus tigrinus, Panthera onca, and Puma concolor presented highest number of records of pathogens and wider distribution of records through Brazilian regions. Records of these pathogens occurred mainly in the Central West and Southeast regions of Brazil. The role of the members of family Felidae as reservoirs of agents of several lethal zoonoses is observed, although leptospirosis presents a register of different serovars, including some non-pathogenic to humans. These results bring to light the importance of preserving and maintaining the natural habitats of these species as a public health measure, in order to prevent the proliferation of these zoonoses, both for humans and animals. The preservation of feline natural environments could minimize possible pathogen exchanges between these species and domestic animals and, consequently, with humans, as well as reducing the likelihood of their direct contact with felines.