Sarcoptes scabiei infestation in a captive lowland tapir (Tapirus terrestris): case report, morphological and molecular genetic mite identification.

Sarcoptes scabiei (Acari: Sarcoptidae) is a globally distributed parasitic mite species, which causes mange in a broad spectrum of domestic and wild mammals. In the present study, we report a case of chronic S. scabiei infestation in a captive lowland tapir (Tapirus terrestris) held in a multi-species exhibit at Vienna Zoo. The adult male showed clinically manifested mange flare-ups three times at an interval of up to 12 months, diagnosed by positive deep-skin scrapings and successfully treated by oral applications of ivermectin (0.1-0.2 mg/kg body weight) and washings with antimicrobial solutions. Clinical symptoms including pruritus, alopecia, erythema, crusts, and superficial bleedings were limited to the axillar and pectoral region, as well as distal limbs. The affected tapir died from underlying bacterial pneumonia during general anesthesia. Skin scrapings, necropsy, and histopathological analysis of mite material (eggs, larvae, and adults) permitted further morphological and molecular identification. The morphological features described here matched the characteristics for the species S. scabiei and molecular data verified morphological identification. Cross-species transmission plays a key role in the expansion of this neglected emerging panzootic disease and urban wildlife could potentially bridge the gap between free-ranging wildlife reservoirs and zoo animals. However, further examinations are needed to detect the primary source of infestation and discover transmission pathways within the zoo.

Molecular pathogen screening of louse flies (Diptera: Hippoboscidae) from domestic and wild ruminants in Austria.

BACKGROUND: Hippoboscid flies (Diptera: Hippoboscidae), also known as louse flies or keds, are obligate blood-sucking ectoparasites of animals, and accidentally of humans. The potential role of hippoboscids as vectors of human and veterinary pathogens is being increasingly investigated, but the presence and distribution of infectious agents in louse flies is still unknown in parts of Europe. Here, we report the use of molecular genetics to detect and characterize vector-borne pathogens in hippoboscid flies infesting domestic and wild animals in Austria. METHODS: Louse flies were collected from naturally infested cattle (n = 25), sheep (n = 3), and red deer (n = 12) across Austria between 2015 and 2019. Individual insects were morphologically identified to species level and subjected to DNA extraction for molecular pathogen screening and barcoding. Genomic DNA from each louse fly was screened for Borrelia spp., Bartonella spp., Trypanosomatida, Anaplasmataceae, Filarioidea and Piroplasmida. Obtained sequences of Trypanosomatida and Bartonella spp. were further characterized by phylogenetic and haplotype networking analyses. RESULTS: A total of 282 hippoboscid flies corresponding to three species were identified: Hippobosca equina (n = 62) collected from cattle, Melophagus ovinus (n = 100) from sheep and Lipoptena cervi (n = 120) from red deer (Cervus elaphus). Molecular screening revealed pathogen DNA in 54.3% of hippoboscids, including infections with single (63.39%), two (30.71%) and up to three (5.90%) distinct pathogens in the same individual. Bartonella DNA was detected in 36.9% of the louse flies. Lipoptena cervi were infected with 10 distinct and previously unreported Bartonella sp. haplotypes, some closely associated with strains of zoonotic potential. DNA of trypanosomatids was identified in 34% of hippoboscids, including the first description of Trypanosoma sp. in H. equina. Anaplasmataceae DNA (Wolbachia spp.) was detected only in M. ovinus (16%), while < 1% of the louse flies were positive for Borrelia spp. and Filarioidea. All hippoboscids were negative for Piroplasmida. CONCLUSIONS: Molecular genetic screening confirmed the presence of several pathogens in hippoboscids infesting domestic and wild ruminants in Austria, including novel pathogen haplotypes of zoonotic potential (e.g. Bartonella spp.) and the first report of Trypanosoma sp. in H. equina, suggesting a potential role of this louse fly as vector of animal trypanosomatids. Experimental transmission studies and expanded monitoring of hippoboscid flies and hippoboscid-associated pathogens are warranted to clarify the competence of these ectoparasites as vectors of infectious agents in a One-Health context.

Vector-borne pathogens in clinically healthy military working dogs in eastern Austria.

Military working dogs have an increased risk of acquiring an infection with vector-borne pathogens due to kennel housing and regular exposure to wildlife and vectors. To evaluate the level of infections in clinically healthy dogs of the Austrian Armed Forces, 94 individuals of the Military Working Dog Training Centre (MWDTC) Kaisersteinbruch/eastern Austria were examined in August 2016, February 2019 and August 2019. A modified Knott test was used to determine the presence of microfilariae, PCR for DNA detection of filarioid nematodes (incl. Dirofilaria), Leishmania spp., piroplasms, Borrelia spp., Bartonella spp. and Anaplasmataceae, and serological examination for antibodies against Borrelia burgdoferi s. l. and Leishmania infantum in all dogs. Two dogs were positive for Dirofilaria repens in the Knott test, and one of them also by PCR. Six clinically healthy dogs (4.2%) were positive for Babesia canis (PCR). In serology, 10 (10.6%) of the dogs were positive for specific antibodies against Borrelia burgdoferi s. l. The results suggest that the current measures against arthropod vector exposure and the pathogens they can transmit are not fully sufficient for these dogs. Further investigations of the tick and mosquito fauna in this area will shed more light on the risk of exposure for both the dogs and the staff of the MWDTC.

Arrival of the Asian tiger mosquito, Aedes albopictus (Skuse, 1895) in Vienna, Austria and initial monitoring activities.

Aedes albopictus was recorded in Vienna, Austria, in August 2020 for the first time. The species was found to occur in three sites within the city; morphology-based monitoring was followed by DNA-barcoding. Mitochondrial COI barcode sequences recovered three different haplotypes, however this data does not reveal whether single or multiple introduction events have occurred. The vicinity of Viennese Ae. albopictus sites to major traffic routes highlights the importance of passive transport for range expansion of this species.

Babesia spp. and Anaplasma phagocytophilum in free-ranging wild ungulates in central Austria.

Free-ranging wild ungulates are widespread in Austria, and act as hosts (i.e. feeding hosts) for ticks, including Ixodes ricinus, and as reservoir hosts for pathogens transmitted by I. ricinus. Due to climate change, the abundance of I. ricinus might be increasing, which could potentially lead to higher prevalences of tick-borne pathogens, such as Babesia spp. and Anaplasma phagocytophilum, some known for their zoonotic potential. Human babesiosis is classified as an emerging zoonosis, but sufficient data of these parasites in central Austria is lacking. In order to assess the abundance of vector-borne pathogens, blood of roe deer (Capreolus capreolus; n = 137), red deer (Cervus elaphus; n = 37), mouflons (Ovis gmelini; n = 2) and chamois (Rupicapra rupicapra; n = 1), was collected and tested for pathogen DNA in two different sampling sites in central Austria. DNA of tick-borne pathogens was detected in 15.5 % (n = 27) of these animals. Babesia capreoli (n = 22 in roe deer; n = 1 in mouflon), Babesia divergens (n = 1, in red deer), and Anaplasma phagocytophilum (n = 4, in roe deer) were detected. DNA sequencing of the 18S rRNA gene of two C. capreolus samples from Upper Austria featured another new genotype of Babesia, which differs in one nucleotide position to B. divergens and B. capreoli, and is intermediate between the main genotypes of B. capreoli and B. divergens within the partial gene sequence analyzed. This study thus confirms that B. capreoli, B. divergens, and A. phagocytophilum are present in free-ranging ungulates in central Austria. Further testing over a longer period is recommended in order to assess the impact of climate change on the prevalence of blood parasites in central Austria.

Absence of blood parasites and other vector-borne pathogens in Alpine marmots (Marmota marmota) in Western Austria.

The importance of vectors and vector-borne diseases (VBDs) is increasing on a global scale. Many vectors and pathogens benefit from global warming and can spread to novel habitats where they were formerly not present, including higher altitudes. Various vector-borne pathogens (VBPs), such as Anaplasma phagocytophilum, have been reported in, for instance, red foxes and wild ungulates in the Western Austrian Alps. However, these animals are known to migrate to lower regions in the winter season, and therefore, it is of interest to investigate if VBPs are also present in mammals faithful to their higher altitude alpine habitat all year round. Blood parasites and other VBPs, namely. Trypanosomatidae, piroplasms, Hepatozoon spp., filarioid helminths, Anaplasmataceae, and Rickettisa spp., were thus analysed with PCR in 148 alpine marmots (Marmota marmota). None of the marmots' blood samples was positive for these VBPs, indicating a low abundance or absence of competent vectors in the alpine region. Alpine marmots seem to be naïve for VBPs (at least in our study area). An overview of VBD agents in other marmot species is given.

Detection of Crenosoma spp., Angiostrongylus vasorum and Aelurostrongylus abstrusus in Gastropods in Eastern Austria.

Canine and feline cardiorespiratory parasites are of utmost relevance in veterinary medicine. Key epizootiological information on major pet metastrongyloids, i.e., Angiostrongylus vasorum and Crenosoma vulpis infecting dogs, and Aelurostrongylus abstrusus and Troglostrongylus brevior infecting cats, is missing from Austria. This study investigated their occurrence in 1320 gastropods collected in the Austrian provinces of Styria, Burgenland, Lower Austria, and in metropolitan Vienna. Metastrongyloid larvae were microscopically detected in 25 samples, and sequence analysis confirmed the presence of metastrongyloids in nine samples, i.e., A. vasorum in one slug (Arion vulgaris) (0.07%), C. vulpis in five slugs (one Limax maximus and four A. vulgaris) (0.4%), A. abstrusus in two A. vulgaris (0.17%), and the hedgehog lungworm Crenosoma striatum was detected in one A. vulgaris. The present study confirms the enzooticity of major cardiorespiratory nematodes in Austria and that canine and feline populations are at risk of infection.

Survey of Zoonotic and Non-zoonotic Vector-Borne Pathogens in Military Horses in Lisbon, Portugal.

Vector-borne diseases of zoonotic and/or veterinary relevance have been increasingly reported in horses globally, although data regarding working and military horses is lacking. Portuguese military horses may constitute a risk group for these pathogens, as they frequently work outdoors in various regions of the country. This study included 101 apparently healthy horses belonging to the Portuguese National Republican Guard. Blood samples were analyzed to determine the presence and prevalence of piroplasms, Anaplasmataceae, Rickettsia spp., and filarioid helminths. Overall 32.7% of the horses gave positive results for Theileria equi. Two genotypes of T. equi were verified. No positive results were recorded for Anaplasma spp., Rickettsia spp., filarioid helminthes, and Babesia caballi. As equine piroplasmosis is a severe infectious tick-borne disease responsible for significant losses in equine production and with numerous impacts in the international movement of horses, adequate treatment, and preventive measures are needed to reduce exposure to vectors and future infections.

Barcoding of the Genus Culicoides (Diptera: Ceratopogonidae) in Austria-An Update of the Species Inventory Including the First Records of Three Species in Austria.

Ceratopogonidae are small nematoceran Diptera with a worldwide distribution, consisting of more than 5400 described species, divided into 125 genera. The genus Culicoides is known to comprise hematophagous vectors of medical and veterinary importance. Diseases transmitted by Culicoides spp. Such as African horse sickness virus, Bluetongue virus, equine encephalitis virus (Reoviridae) and Schmallenberg virus (Bunyaviridae) affect large parts of Europe and are strongly linked to the spread and abundance of its vectors. However, Culicoides surveillance measures are not implemented regularly nor in the whole of Austria. In this study, 142 morphologically identified individuals were chosen for molecular analyses (barcoding) of the mitochondrial cytochrome c oxidase subunit I gene (mt COI). Molecular analyses mostly supported previous morphologic identification. Mismatches between results of molecular and morphologic analysis revealed three new Culicoides species in Austria, Culicoides gornostaevae Mirzaeva, 1984, which is a member of the Obsoletus group, C. griseidorsum Kieffer, 1918 and C. pallidicornis Kieffer, 1919 as well as possible cryptic species. We present here the first Austrian barcodes of the mt COI region of 26 Culicoides species and conclude that barcoding is a reliable tool with which to support morphologic analysis, especially with regard to the difficult to identify females of the medically and economically important genus Culicoides.

Toxocara vitulorum infection in a yak (Bos mutus grunniens) calf from Tyrol (Austria).

The domestic yak Bos mutus grunniens is an important livestock animal in parts of Asia, especially of the Himalayan region, where people rely on it for meat, wool, milk and labour. In its countries of origin, the yak is commonly infected with the ascarid Toxocara vitulorum. This parasite mainly infects cattle (Bos taurus) and domestic buffalo (Bubalus bubalus) and is most commonly found in sub-tropical regions, but has been occasionally reported in more temperate climates, including several Central European countries. Here we describe a fatal case of toxocarosis in a yak calf in Tyrol in May 2018, which is the first report of these parasites in yaks in Austria. A moribund calf had to be euthanized and gross pathology showed masses of cream-coloured, up to 25 cm long nematodes filling the whole of the small intestine, as well as parts of the colon. PCR of parts of the mitochondrial cytochrome c oxidase subunit I gene was performed and sequence analysis confirmed the helminths as Toxocara vitulorum.

Screening of wild ruminants from the Kaunertal and other alpine regions of Tyrol (Austria) for vector-borne pathogens.

Knowledge about vector-borne pathogens important for human and veterinary medicine in wild ruminants in Tyrol (Austria) is scarce. Blood samples from Alpine ibex (Capra ibex; n = 44), Alpine chamois (Rupicapra rupicapra; n = 21), roe deer (Capreolus capreolus; n = 18) and red deer (Cervus elaphus; n = 6) were collected over a period of 4 years (2015-2018) in four regions in North Tyrol, with a primary focus on the Kaunertal. Blood spots on filter paper were tested for the presence of DNA of vector-borne pathogens (Anaplasmataceae, Piroplasmida, Rickettsia and filarioid helminths). Anaplasma phagocytophilum and Babesia capreoli were detected in two of 89 (2.3%) blood samples. Rickettsia spp., Theileria spp. and filarioid helminths were not documented. One Alpine chamois was positive for A. phagocytophilum and B. capreoli. Moreover, an ibex from the Kaunertal region was positive for A. phagocytophilum. While the ibex was a kid less than 1 year old, the chamois was an adult individual. Further research is recommended to evaluate effects of climate change on infection rates of North Tyrolean wild ruminants by these pathogens and the distribution of their vectors.