Browsing by Author "Pfeffer, Martin"

Tick-borne encephalitis virus (TBEV) strain A104 was isolated from the brain of a yellow-necked mouse in Austria in 1990. The complete genome sequence was 11,097 nucleotides long. Comparison with TBEV prototype strain Neudoerfl showed 32 amino acid exchanges and the absence of an internal poly(A) stretch within the 3' noncoding region.

We present pyrosequencing data and phylogenetic analysis for the full genome of Yug Bogdanovac virus (YBV), a member of the Vesicular stomatitis virus serogroup of the Rhabdoviridae isolated from a pool of Phlebotomus perfiliewi sandflies collected in Serbia in 1976. YBV shows very low nucleotide identities to other members of the Vesicular stomatitis virus serogroup and does not contain a reading frame for C'/C proteins.

Tick-borne encephalitis (TBE) is the most important viral infection transmitted by ticks in Central Europe In Germany where TBE was classified as a notifiable disease in 2001 a highly variable number of clinically apparent human cases was reported in the last few years ranging from the lowest number of 238 in 2007 to a maximum of 546 in 2006 The dynamics of the virus and its vector tick remain poorly understood We investigated a highly active TBE focus in south-eastern Germany where from 2003 to 2008 a total of 9 clinical human cases was diagnosed Three out of these 9 cases were fatal indicating an unusually high mortality rate possibly due to a highly virulent TBEV strain From 2005 till 2008 2150 Ixodes ricinus ticks were collected and tested for the presence of TBE virus Five TBEV-positive ticks were detected by real-time RT-PCR A viable virus strain was isolated from one of the positive ticks sampled in 2005 This is the first TBE virus isolate from a tick in Germany for 30 years Sequencing of the full-length genome of this virus strain (AS 33) revealed 2 unique amino acid substitutions in the envelope protein known to play a role in the pathogenicity of TBE virus Amplification of the envelope gene using 2 TBEV-PCR-positive ticks from 2006 also showed these particular mutations indicating that this TBE virus strain was present in at least 2 consecutive years The entire sampling area was divided into smaller sectors for the exact location of TBEV-positive ticks Virus-positive ticks were found to be randomly distributed throughout the investigated focus which is used as recreational area by the local people (C) 2009 Elsevier GmbH All rights reserved

In order to obtain a better understanding of tick-borne encephalitis virus (TBEV) strain movements in central Europe the E gene sequences of 102 TBEV strains collected from 1953 to 2011 at 38 sites in the Czech Republic, Slovakia, Austria and Germany were determined. Bayesian analysis suggests a 350-year history of evolution and spread in central Europe of two main lineages, A and B. In contrast to the east to west spread at the Eurasian continent level, local central European spreading patterns suggest historic west to east spread followed by more recent east to west spread. The phylogenetic and network analyses indicate TBEV ingressions from the Czech Republic and Slovakia into Germany via landscape features (Danube river system), biogenic factors (birds, red deer) and anthropogenic factors. The identification of endemic foci showing local genetic diversity is of paramount importance to the field as these will be a prerequisite for in-depth analysis of focal TBEV maintenance and long-distance TBEV spread.

Background: Tularemia re-emerged in Germany starting in 2004 (with 39 human cases from 2004 to 2007) after over 40 years of only sporadic human infections. The reasons for this rise in case numbers are unknown as is the possible reservoir of the etiologic agent Francisella (F.) tularensis. No systematic study on the reservoir situation of F. tularensis has been published for Germany so far. Methods: We investigated three areas six to ten months after the initial tularemia outbreaks for the presence of F. tularensis among small mammals, ticks/fleas and water. The investigations consisted of animal live-trapping, serologic testing, screening by real-time-PCR and cultivation. Results: A total of 386 small mammals were trapped. F. tularensis was detected in five different rodent species with carrier rates of 2.04, 6.94 and 10.87% per trapping area. None of the ticks or fleas (n = 432) tested positive for F. tularensis. We were able to demonstrate F. tularensis-specific DNA in one of 28 water samples taken in one of the outbreak areas. Conclusion: The findings of our study stress the need for long-term surveillance of natural foci in order to get a better understanding of the reasons for the temporal and spatial patterns of tularemia in Germany.