Vor, Torsten

[["dc.bibliographiccitation.firstpage","79"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Experimental and Applied Acarology"],["dc.bibliographiccitation.lastpage","94"],["dc.bibliographiccitation.volume","53"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Loedige, Christina"],["dc.contributor.author","Alings, M."],["dc.contributor.author","Vor, T."],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T09:01:16Z"],["dc.date.available","2018-11-07T09:01:16Z"],["dc.date.issued","2011"],["dc.description.abstract","The spatio-temporal attachment site patterns of ticks feeding on their hosts can be of significance if co-feeding transmission (i.e. from tick to tick without a systemic infection of the host) of pathogens affects the persistence of a given disease. Using tick infestation data on roe deer, we analysed preferred attachment sites and niche width of Ixodes ticks (larvae, nymphs, males, females) and investigated the degree of inter- and intrastadial aggregation. The different development stages showed rather consistent attachment site patterns and relative narrow feeding site niches. Larvae were mostly found on the head and on the front legs of roe deer, nymphs reached highest densities on the head and highest adult densities were found on the neck of roe deer. The tick stages feeding (larvae, nymphs, females) on roe deer showed high degrees of intrastadial spatial aggregation, whereas males did not. Male ticks showed large feeding site overlap with female ticks. Feeding site overlap between larval-female and larval-nymphal ticks did occur especially during the months May-August on the head and front legs of roe deer and might allow pathogen transmission via co-feeding. Tick density, niche width and niche overlap on roe deer are mainly affected by seasonality, reflecting seasonal activity and abundance patterns of ticks. Since different tick development stages occur spatially and temporally clustered on roe deer, transmission experiments of tick-borne pathogens are urgently needed."],["dc.description.sponsorship","Federal Ministry of Education and Research (BMBF) [1363120]"],["dc.identifier.doi","10.1007/s10493-010-9378-4"],["dc.identifier.isi","000284651000009"],["dc.identifier.pmid","20585837"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5988"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/24378"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1572-9702"],["dc.relation.issn","0168-8162"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Attachment site selection of ticks on roe deer, Capreolus capreolus"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","42"],["dc.bibliographiccitation.journal","International Journal of Health Geographics"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Zucchini, Walter"],["dc.contributor.author","Schomaker, Philipp"],["dc.contributor.author","Vor, Torsten"],["dc.contributor.author","Hagedorn, Peter"],["dc.contributor.author","Niedrig, Matthias"],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T08:40:23Z"],["dc.date.available","2018-11-07T08:40:23Z"],["dc.date.issued","2010"],["dc.description.abstract","Background: Tick-borne encephalitis (TBE) virus can cause severe symptoms in humans. The incidence of this vector-borne pathogen in humans is characterised by spatial and temporal heterogeneity. To explain the variation in reported human TBE cases per county in southern Germany, we designed a time-lagged, spatially-explicit model that incorporates ecological, environmental, and climatic factors. Results: We fitted a logistic regression model to the annual counts of reported human TBE cases in each of 140 counties over an eight year period. The model controlled for spatial autocorrelation and unexplained temporal variation. The occurrence of human TBE was found to be positively correlated with the proportions of broad-leafed, mixed and coniferous forest cover. An index of forest fragmentation was negatively correlated with TBE incidence, suggesting that infection risk is higher in fragmented landscapes. The results contradict previous evidence regarding the relevance of a specific spring-time temperature regime for TBE epidemiology. Hunting bag data of roe deer (Capreolus capreolus) in the previous year was positively correlated with human TBE incidence, and hunting bag density of red fox (Vulpes vulpes) and red deer (Cervus elaphus) in the previous year were negatively correlated with human TBE incidence. Conclusions: Our approach suggests that a combination of landscape and climatic variables as well as host-species dynamics influence TBE infection risk in humans. The model was unable to explain some of the temporal variation, specifically the high counts in 2005 and 2006. Factors such as the exposure of humans to infected ticks and forest rodent population dynamics, for which we have no data, are likely to be explanatory factors. Such information is required to identify the determinants of TBE more reliably. Having records of TBE infection sites at a finer scale would also be necessary."],["dc.identifier.doi","10.1186/1476-072X-9-42"],["dc.identifier.isi","000282310900001"],["dc.identifier.pmid","20707897"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5662"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19220"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Biomed Central Ltd"],["dc.relation.issn","1476-072X"],["dc.rights","CC BY 2.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.0"],["dc.title","Determinants of tick-borne encephalitis in counties of southern Germany, 2001-2008"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","641"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Vector-Borne and Zoonotic Diseases"],["dc.bibliographiccitation.lastpage","647"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Achazi, Katharina"],["dc.contributor.author","Ruzek, Daniel"],["dc.contributor.author","Donoso-Mantke, Oliver"],["dc.contributor.author","Schlegel, Mathias"],["dc.contributor.author","Ali, Hanan Sheikh"],["dc.contributor.author","Wenk, Mathias"],["dc.contributor.author","Schmidt-Chanasit, Jonas"],["dc.contributor.author","Ohlmeyer, Lutz"],["dc.contributor.author","Ruehe, Ferdinand"],["dc.contributor.author","Vor, Torsten"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Kallies, Rene"],["dc.contributor.author","Ulrich, Rainer G."],["dc.contributor.author","Niedrig, Matthias"],["dc.date.accessioned","2018-11-07T08:55:21Z"],["dc.date.available","2018-11-07T08:55:21Z"],["dc.date.issued","2011"],["dc.description.abstract","Introduction: Tick-borne encephalitis virus (TBEV) causes one of the most important flavivirus infections of the central nervous system, affecting humans in Europe and Asia. It is mainly transmitted by the bite of an infected tick and circulates among them and their vertebrate hosts. Until now, TBE risk analysis in Germany has been based on the incidence of human cases. Because of an increasing vaccination rate, this approach might be misleading, especially in regions of low virus circulation. Method: To test the suitability of rodents as a surrogate marker for virus spread, laboratory-bred Microtus arvalis voles were experimentally infected with TBEV and analyzed over a period of 100 days by real-time (RT)-quantitative polymerase chain reaction. Further, the prevalence of TBEV in rodents trapped in Brandenburg, a rural federal state in northeastern Germany with autochthonous TBE cases, was determined and compared with that in rodents from German TBE risk areas as well as TBE nonrisk areas. Results: In experimentally infected M. arvalis voles, TBEV was detectable in different organs for at least 3 months and in blood for 1 month. Ten percent of all rodents investigated were positive for TBEV. However, in TBE risk areas, the infection rate was higher compared with that of areas with only single human cases or of nonrisk areas. TBEV was detected in six rodent species: Apodemus agrarius, Apodemus flavicollis, Apodemus sylvaticus, Microtus agrestis, Microtus arvalis, and Myodes glareolus. M. glareolus showed a high infection rate in all areas investigated. Discussion and Conclusion: The infection experiments proved that TBEV can be reliably detected in infected M. arvalis voles. These voles developed a persistent TBE infection without clinical symptoms. Further, the study showed that rodents, especially M. glareolus, are promising sentinels particularly in areas of low TBEV circulation."],["dc.identifier.doi","10.1089/vbz.2010.0236"],["dc.identifier.isi","000291717500009"],["dc.identifier.pmid","21548766"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22878"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Mary Ann Liebert, Inc"],["dc.relation.issn","1557-7759"],["dc.relation.issn","1530-3667"],["dc.title","Rodents as Sentinels for the Prevalence of Tick-Borne Encephalitis Virus"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","323"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Parasitology Research"],["dc.bibliographiccitation.lastpage","335"],["dc.bibliographiccitation.volume","108"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Vor, Torsten"],["dc.contributor.author","Hagedorn, Peter"],["dc.contributor.author","Niedrig, Matthias"],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T08:59:57Z"],["dc.date.available","2018-11-07T08:59:57Z"],["dc.date.issued","2011"],["dc.description.abstract","Identifying factors affecting individual vector burdens is essential for understanding infectious disease systems. Drawing upon data of a rodent monitoring programme conducted in nine different forest patches in southern Hesse, Germany, we developed models which predict tick (Ixodes spp. and Dermacentor spp.) burdens on two rodent species Apodemus flavicollis and Myodes glareolus. Models for the two rodent species were broadly similar but differed in some aspects. Patterns of Ixodes spp. burdens were influenced by extrinsic factors such as season, unexplained spatial variation (both species), relative humidity and vegetation cover (A. flavicollis). We found support for the 'body mass' (tick burdens increase with body mass/age) and for the 'dilution' hypothesis (tick burdens decline with increasing rodent densities) and little support for the 'sex-bias' hypothesis (both species). Surprisingly, roe deer densities were not correlated with larvae counts on rodents. Factors influencing the mean burden did not significantly explain the observed dispersion of tick counts. Co-feeding aggregations, which are essential for tick-borne disease transmission, were mainly found in A. flavicollis of high body mass trapped in areas with fast increase in spring temperatures. Locally, Dermacentor spp. appears to be an important parasite on A. flavicollis and M. glareolus. Dermacentor spp. was rather confined to areas with higher average temperatures during the vegetation period. Nymphs of Dermacentor spp. mainly fed on M. glareolus and were seldom found on A. flavicollis. Whereas Ixodes spp. is the dominant tick genus in woodlands of our study area, the distribution and epidemiological role of Dermacentor spp. should be monitored closely."],["dc.description.sponsorship","Federal Ministry of Education and Research (BMBF) [1363120]"],["dc.identifier.doi","10.1007/s00436-010-2065-x"],["dc.identifier.isi","000286472100009"],["dc.identifier.pmid","20878183"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/7323"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/24029"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0932-0113"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Factors affecting patterns of tick parasitism on forest rodents in tick-borne encephalitis risk areas, Germany"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","18"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Medical and Veterinary Entomology"],["dc.bibliographiccitation.lastpage","25"],["dc.bibliographiccitation.volume","26"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Vor, T."],["dc.contributor.author","Hagedorn, Peter"],["dc.contributor.author","Niedrig, M."],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T09:13:17Z"],["dc.date.available","2018-11-07T09:13:17Z"],["dc.date.issued","2012"],["dc.description.abstract","In order to identify variables associated with the presence of the tick-borne encephalitis (TBE) virus, we conducted a serological survey of roe deer [Capreolus capreolus (Artiodactyla: Cervidae, Linnaeus 1758)] in three forest districts of southern Hesse, Germany. Overall, 24 out of 105 (22.9%) of the sera were positive (=1 : 10 plaque reduction neutralization test). Using a logistic regression approach, we found that unexplained spatial variation, indexed roe deer density (positive correlation), hind foot length of the tested roe deer (positive correlation) and infestation with female Ixodes spp. ticks (negative correlation) predicted the probability of TBE virus antibody presence in individual roe deer sera. Spring temperature increase and host sex were rejected as explanatory variables. We found considerable differences in TBE virus antibody seroprevalence (50.0% vs. 17.6%) between two forest districts located in the same county; this finding questions the current county-resolution of public health recordings. Given the high seroprevalence of roe deer and the considerable explanatory power of our model, our approach appears suitable to delineate science-based risk maps at a smaller spatial scale and to abandon the current human incidence per county criterion. Importantly, using roe deer as sentinels would eliminate the inherent bias of risk maps based on human incidence (varying levels of immunization and exposure of humans)."],["dc.description.sponsorship","Federal Ministry of Education and Research (BMBF) [1363120]"],["dc.identifier.doi","10.1111/j.1365-2915.2011.00961.x"],["dc.identifier.isi","000299333500003"],["dc.identifier.pmid","21592155"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/27138"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","0269-283X"],["dc.title","Determinants of tick-borne encephalitis virus antibody presence in roe deer (Capreolus capreolus) sera"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","73"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Experimental and Applied Acarology"],["dc.bibliographiccitation.lastpage","84"],["dc.bibliographiccitation.volume","52"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Loedige, Christina"],["dc.contributor.author","Alings, Matthias"],["dc.contributor.author","Vor, Torsten"],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T08:39:42Z"],["dc.date.available","2018-11-07T08:39:42Z"],["dc.date.issued","2010"],["dc.description.abstract","Despite the importance of roe deer as a host for Ixodes ticks in central Europe, estimates of total tick burden on roe deer are not available to date. We aimed at providing (1) estimates of life stage and sex specific (larvae, nymphs, males and females, hereafter referred to as tick life stages) total Ixodes burden and (2) equations which can be used to predict the total life stage burden by counting the life stage on a selected body area. Within a period of 1A1/2A years, we conducted whole body counts of ticks from 80 hunter-killed roe deer originating from a beech dominated forest area in central Germany. Averaged over the entire study period (winter 2007-summer 2009), the mean tick burden per roe deer was 64.5 (SE +/- A 10.6). Nymphs were the most numerous tick life stage per roe deer (23.9 +/- A 3.2), followed by females (21.4 +/- A 3.5), larvae (10.8 +/- A 4.2) and males (8.4 +/- A 1.5). The individual tick burden was highly aggregated (k = 0.46); levels of aggregation were highest in larvae (k = 0.08), followed by males (k = 0.40), females (k = 0.49) and nymphs (k = 0.71). To predict total life stage specific burdens based on counts on selected body parts, we provide linear equations. For estimating larvae abundance on the entire roe deer, counts can be restricted to the front legs. Tick counts restricted to the head are sufficient to estimate total nymph burden and counts on the neck are appropriate for estimating adult ticks (females and males). In order to estimate the combined tick burden, tick counts on the head can be used for extrapolation. The presented linear models are highly significant and explain 84.1, 77.3, 90.5, 91.3, and 65.3% (adjusted R (2)) of the observed variance, respectively. Thus, these models offer a robust basis for rapid tick abundance assessment. This can be useful for studies aiming at estimating effects of abiotic and biotic factors on tick abundance, modelling tick population dynamics, modelling tick-borne pathogen transmission dynamics or assessing the efficacy of acaricides."],["dc.description.sponsorship","Federal Ministry of Education and Research (BMBF) [1363120]"],["dc.identifier.doi","10.1007/s10493-010-9341-4"],["dc.identifier.isi","000280596100008"],["dc.identifier.pmid","20204470"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5009"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19060"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","0168-8162"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Abundance estimation of Ixodes ticks (Acari: Ixodidae) on roe deer (Capreolus capreolus)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","39"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Medical and Veterinary Entomology"],["dc.bibliographiccitation.lastpage","45"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Loedige, Christina"],["dc.contributor.author","Alings, M."],["dc.contributor.author","Vor, T."],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T08:59:05Z"],["dc.date.available","2018-11-07T08:59:05Z"],["dc.date.issued","2011"],["dc.description.abstract","Macroparasites feeding on wildlife hosts follow skewed distributions for which basic statistical approaches are of limited use. To predict Ixodes spp. tick burden on roe deer, we applied Generalized Additive Models for Location, Scale and Shape (GAMLSS) which allow incorporating a variable dispersion. We analysed tick burden of 78 roe deer, sampled in a forest region of Germany over a period of 20 months. Assuming a negative binomial error distribution and controlling for ambient temperature, we analysed whether host sex and body mass affected individual tick burdens. Models for larval and nymphal tick burden included host sex, with male hosts being more heavily infested than female ones. However, the influence of host sex on immature tick burden was associated with wide standard errors (nymphs) or the factor was marginally significant (larvae). Adult tick burden was positively correlated with host body mass. Thus, controlled for host body mass and ambient temperature, there is weak support for sex-biased parasitism in this system. Compared with models which assume linear relationships, GAMLSS provided a better fit. Adding a variable dispersion term improved only one of the four models. Yet, the potential of modelling dispersion as a function of variables appears promising for larger datasets."],["dc.description.sponsorship","Federal Ministry of Education and Research (BMBF) [1363120]"],["dc.identifier.doi","10.1111/j.1365-2915.2010.00929.x"],["dc.identifier.isi","000287362900007"],["dc.identifier.pmid","21118286"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/23805"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","1365-2915"],["dc.relation.issn","0269-283X"],["dc.title","Body-mass or sex-biased tick parasitism in roe deer (Capreolus capreolus)? A GAMLSS approach"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","405"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Experimental and Applied Acarology"],["dc.bibliographiccitation.lastpage","417"],["dc.bibliographiccitation.volume","51"],["dc.contributor.author","Vor, Torsten"],["dc.contributor.author","Kiffner, Christian"],["dc.contributor.author","Hagedorn, Peter"],["dc.contributor.author","Niedrig, Matthias"],["dc.contributor.author","Ruehe, Ferdinand"],["dc.date.accessioned","2018-11-07T08:40:46Z"],["dc.date.available","2018-11-07T08:40:46Z"],["dc.date.issued","2010"],["dc.description.abstract","In our study we assessed the tick burden on roe deer (Capreolus capreolus L.) in relation to age, physical condition, sex, deer density and season. The main objective was to find predictive parameters for tick burden. In September 2007, May, July, and September 2008, and in May and July 2009 we collected ticks on 142 culled roe deer from nine forest departments in Southern Hesse, Germany. To correlate tick burden and deer density we estimated deer density using line transect sampling that accounts for different detectability in March 2008 and 2009, respectively. We collected more than 8,600 ticks from roe deer heads and necks, 92.6% of which were Ixodes spp., 7.4% Dermacentor spp. Among Ixodes, 3.3% were larvae, 50.5% nymphs, 34.8% females and 11.4% males, with significant seasonal deviation. Total tick infestation was high, with considerable individual variation (from 0 to 270 ticks/deer). Adult tick burden was positively correlated with roe deer body indices (body mass, age, hind foot length). Significantly more nymphs were found on deer from forest departments with high roe deer density indices, indicating a positive correlation with deer abundance. Overall, tick burden was highly variable. Seasonality and large scale spatial characteristics appeared to be the most important factors affecting tick burden on roe deer."],["dc.identifier.doi","10.1007/s10493-010-9337-0"],["dc.identifier.isi","000279588600009"],["dc.identifier.pmid","20099011"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5008"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/19311"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0168-8162"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Tick burden on European roe deer (Capreolus capreolus)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]