Infections with intravascular digenean trematodes of the Spirorchiidae family (spirorchiidoses) are of great conservation concern both in marine and freshwater turtles due to their pathogenic potential. Between 2014 and 2021, Spirorchis sp. infections associated with granulomatous inflammation and sudden death were detected in European pond turtles ( Emys orbicularis ) from three conservation breeding facilities in Switzerland. Blood fluke eggs associated with lesions were found in the intestine, spleen, testis, skeletal musculature, heart, kidneys, stomach, pancreas, liver, lung, and meninges from nine pond turtles submitted for necropsy and in the intestinal content from five of these animals. Two novel polymerase chain reactions (PCRs) targeting the 28S ribosomal RNA gene and the ITS2 region and subsequent sequencing revealed 100% nucleotide identity with a Spirorchis sp. previously isolated from an Escambia map turtle ( Graptemys ernsti ) in the USA. Our findings suggest a spill-over event secondary to direct or indirect contact with invasive North American turtle species in Switzerland. We describe the clinical, haematological, ultrasonographical, endoscopical, parasitological, pathological, and molecular findings associated with spirorchiid blood fluke infections of the Spirorchis genus in E. orbicularis , as well as the biosecurity measures that were developed to prevent the spread of this parasite among breeding and highly endangered free-ranging E. orbicularis populations in Switzerland.

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European hedgehogs (Erinaceus europaeus) have a high exposure to various ticks, which could transmit pathogens with direct health significance for the host and may have zoonotic potential. Tickborne meningoencephalitis (FSME) is an important tick-borne disease in Switzerland, caused by the tickborne encephalitis virus. About its occurrence in the European hedgehog population is little known. The present study examined various organs, blood and ticks of 65 European hedgehogs to obtain data of FSME virus presence in this species in Switzerland. Real-time RT-PCR from the lungs, liver, spleen and kidney of 56 hedgehogs and of 114 infesting ticks (Ixodes hexagonus or Ixodes ricinus) were used for the detection of viral RNA. In addition, 19 blood samples were tested for antibodies against FSME by ELISA. FSME virus antibodies were detected for the first time in the serum of a European hedgehog. Lung and spleen tissue samples of the same animal tested also weak virus positive on RT-PCR. Clinically, the hedgehog showed neurological symptoms, although these symptoms could have originated from an other diseases. No viral RNA was detected in any of the ticks. This study could not confirm if the meningoencephalitis in the hedgehog was triggered by the FSME viral infection. Nevertheless, the simultaneous detection of antibodies and virus RNA in the same animal makes the European hedgehog a competent host of the tick-borne encephalitis virus and leads to the assumption that this species can act as a reservoir.

Conservation of endangered animal species is a major task of zoos. Husbandry and breeding of Atlantic puffins Fratercula arctica in captivity is challenging. In 2019, the entire chick population (n = 4 chicks) in Berne Animal Park’s Atlantic puffin colony (Bern, Switzerland) died within 7 d. Due to supply constraints, the chicks had been fed with wild-caught European minnows Phoxinus phoxinus. At necropsy, the main pathological finding in all deceased puffin chicks was a multifocal, moderate to severe subacute heterophilic and granulomatous enteritis with intralesional adult trematodes and eggs. Metacercariae surrounded by few necrotic cells and scattered macrophages were found in the brain and spinal cord of the food fish. Additional microbiological analyses of both the puffin chicks and fish were unremarkable. Diplostomum phoxini DNA could be identified in formalin-fixed paraffin-embedded tissue from the small intestine of all puffin chicks and European minnows following PCR and sequencing of the 18S ribosomal RNA gene and the internal transcribed spacer (ITS1) region. This report illustrates the importance of intensive health checks of food fish for animal species kept in captivity.