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Unterwalden, Austria

Jungnick S.,Bavarian Health and Food Safety Authority | Jungnick S.,National Reference Center for Borrelia | Margos G.,Bavarian Health and Food Safety Authority | Margos G.,National Reference Center for Borrelia | And 14 more authors.
International Journal of Medical Microbiology | Year: 2015

MultiLocus sequence typing (MLST) is considered a powerful method to unveil relationships within bacterial populations and it constitutes an economical and fast alternative to whole genome sequencing. We used this method to understand whether there are differences in human pathogenicity within and between different Borrelia burgdorferi sensu lato species. Therefore, 136 strains from human patients or ticks from Europe were included in MLST analyses. The scheme employed used eight chromosomally located housekeeping genes (i.e. clpA, clpX, nifS, pepX, pyrG, recG, rplB and uvrA). We investigated Borrelia afzelii, one of the predominant species in Europe, and B. burgdorferi sensu stricto (s.s.), because it allowed comparative analysis to strains from the USA. We typed 113 patient isolates as well as 23 tick isolates. For further comparative purposes an additional 746 strains from Europe and the USA were included from the MLST website http://borrelia.mlst.net. We observed an overlap of the B. burgdorferi s.s. populations from Europe and the USA isolated from human patients while there was no overlap of the populations found in tick vectors. Further results indicate that B. afzelii was significantly less associated with disseminated infection than B. burgdorferi s.s. and that B. burgdorferi s.s. from Europe caused neuroborreliosis to a significantly greater extent than B. afzelii or B. burgdorferi s.s. in the USA. Our data suggest that there may be an evolutionary basis of differential interspecies pathogenicity in Borrelia. This was not evident within Borrelia species: we found the same sequence types in patients with disseminated or localized symptoms when the number of strains was sufficiently high. We hypothesize that the finding that B. burgdorferi s.s. in Europe is much more associated with neuroborreliosis than in the USA maybe linked to factor(s) related to the human host, the tick vector or the bacterium itself (e.g. plasmid content and structure). © 2015 Elsevier GmbH. Source

Sonnleitner S.T.,Innsbruck Medical University | Sonnleitner S.T.,Dr. Gernot Walder GmbH | Margos G.,University of Bath | Wex F.,Innsbruck Medical University | And 5 more authors.
Ticks and Tick-borne Diseases | Year: 2015

Seroprevalences were determined by testing sera of 1607 blood donors from North, East, and South Tyrol. In the Tyrols, the continental divide delimitates areas with high seroprevalences of IgG antibodies against Borrelia burgdorferi sensu lato in the North (7.2%) from areas with low seroprevalences in the South (1.5%). To determine Borrelia prevalences in unfed Ixodes ricinus ticks, 755 questing ticks were tested by PCR. Prevalences in nymphal and adult ticks were found to be 19.7% ( n = 132) and 21.5% ( n = 205) in North Tyrol and 23% ( n = 43) and 23.7% ( n = 376) in South Tyrol, respectively. Sequencing of 46 Borrelia-positive ticks yielded 74% Borrelia ( B.) afzelii, 11% B. garinii, 7% B. lusitaniae, 7% B. burgdorferi sensu stricto, and 2% B. valaisiana infections. Distinct genetic clusters could not be delimitated on either side of the continental divide. This study describes occurrence and geographic dispersion of Borrelia spp. in the Tyrols, discusses possible reasons for significant differences in human seroprevalence, and indicates that prevalence of Borrelia in vector ticks is not a direct predictive factor for the local seroprevalence in humans. © 2015 Published by Elsevier GmbH. Source

Sonnleitner S.T.,Dr. Gernot Walder GmbH | Fritz J.,Informatics and Health Economics | Bednarska M.,Innsbruck Medical University | Baumgartner R.,Dr. Gernot Walder GmbH | And 9 more authors.
Transfusion | Year: 2014

After malaria, babesiosis is the second most common transfusion-transmitted parasitic disease in the United States. In Europe, one reported transfusion case, concerning Babesiamicroti, occurred in Germany. Study Design and Methods Due to the fact that Babesia spp. are present in Tyrolean ticks, the aim of this study is to assess the occurrence of immunoglobulin (Ig)G antibodies against the Babesia divergens complex, including B.divergens and Babesia venatorum (EU1), as well as B.microti by screening a representative collective of 988 blood donors from North and East Tyrol (Austria) with indirect immunofluorescence antibody test. Additionally, we investigated 206 local ixodid ticks for the presence of babesial DNA by polymerase chain reaction. Results Seroprevalence data resulted in rates of 2.1% for IgG antibodies against the B.divergens complex and 0.6% against B.microti in Tyrolean blood donors. All sera could be confirmed by independent retesting. Our data indicate that cross-reactivity is high between B.divergens and B.venatorum and lower than 19.8% between B.divergens and B.microti. Conclusions This study shows that Babesia spp. are present in the Tyrols, which blood donors come into serologic contact with, and that we have to consider how to sustain blood product safety concerning this new challenge. Additionally, it is the first description of B.venatorum in the Tyrols, found in one Ixodes ricinus at the Italian border. © 2014 AABB. Source

Sonnleitner S.T.,Dr. Gernot Walder GmbH | Lundstrom J.,Uppsala University | Baumgartner R.,Dr. Gernot Walder GmbH | Schennach H.,University of Innsbruck | And 6 more authors.
Vector-Borne and Zoonotic Diseases | Year: 2014

Seroprevalence rates for immunoglobulin G (IgG) antibodies to Tahyna virus (TAHV) and Inkoo virus (INKV) were determined in sera of 1630 blood donors from North, East, and South Tyrol by immunofluorescence assays (IFAs) and confirmatory serum neutralization tests (SNTs). Ten sera (0.6%) reacted positive by TAHV IFA, five of which (0.3%) were confirmed by SNT. Eleven sera (0.7%) reacted positive in the INKV IFA; only one thereof (0.06%) was verified by subsequent SNT. To identify the source of infections, mosquitoes were trapped at 18 sampling sites in the study area, resulting in the collection of 2571 adult mosquitoes: 1254 individuals of the genus Aedes (48.8% of total) including A. albopictus, 640 Culex (24.9%), 303 Coquillettidia (11.8%), 252 Ochlerotatus (9.8%), 49 Anopheles (1.9%), and 73 mosquitoes of the genus Culiseta (2.8%). The mosquitoes were pooled according to species, trapping site, and time, and were tested by RT-PCR for the presence of California serogroup orthobunyavirus nucleic acids. PCR amplification products were obtained in five of 195 pools (2.6%), and all were identified as TAHVs by subsequent sequencing. This represents the first evidence of TAHV circulation and human exposure in the Tyrols and in the alpine region in general. Interestingly, all TAHV sequences were identified in Culex pipiens/torrentium mosquitoes. Whether other California serogroup orthobunyaviruses such as INKV are also circulating in this area is subject of further investigations on larger numbers of mosquitoes. © Mary Ann Liebert, Inc. Source

Duscher G.G.,University of Veterinary Medicine Vienna | Wetscher M.,University of Veterinary Medicine Vienna | Baumgartner R.,Dr. Gernot Walder GmbH | Walder G.,Dr. Gernot Walder GmbH
Ticks and Tick-borne Diseases | Year: 2015

A large majority of Austrian citizens are aware of tick-borne encephalitis (TBE), consequently reflected by a high vaccination rate of 85%. In return, risk assessment and disease mapping on human cases might be hampered due to high and inhomogeneous vaccination rates and travel habitats of humans. The roe deer was used to obtain a starting point for the integral view on the actual risk of TBE in Austria. The roe deer exhibits several attributes which makes it suitable as an indicator species: the roe deer has a restricted home range and it is known to be a heavy tick carrier. Furthermore it sero-converts after infection with TBE, but no outbreak occurs. Sera from 945 roe deer were obtained from all over Austria and screened with IFAT for the antibodies against TBE. Twenty-two positive samples, 2.4%, and 17 samples at the borderline titre of 1:16 were identified. The majority of the positive samples, 70.6%, were located in known TBE areas based on human cases. Further research is needed to confirm or reject new endemic foci of TBE transmission. © 2015 The Authors. Source

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