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

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.