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The intracellular bacteria Anaplasma spp. and Coxiella burnetii and the tick-borne encephalitis virus (TBEV) are tick-transmitted pathogens circulating in the southern German sheep population. Knowledge of interaction among Anaplasma spp., C. burnetii and TBEV in sheep is lacking, but together they might promote and reinforce disease progression. The current study aimed to identify co-exposure of sheep to Anaplasma spp., C. burnetii and TBEV. For this purpose, 1,406 serum samples from 36 sheep flocks located in both southern German federal states, Baden-Wuerttemberg and Bavaria, were analysed by ELISAs to determine the antibody levels of the three pathogens. Inconclusive and positive results from the TBEV ELISA were additionally confirmed by a serum neutralisation assay. The proportion of sheep with antibodies against Anaplasma spp. (47.2%), C. burnetii (3.7%) and TBEV (4.7%) differed significantly. Significantly more flocks with Anaplasma spp. seropositive sheep (91.7%) were detected than flocks with antibodies against TBEV (58.3%) and C. burnetii (41.7%), but there was no significant difference between the number of flocks which contained TBEV and C. burnetii seropositive sheep. Seropositivity against at least two pathogens was detected in 4.7% of sheep from 20 flocks. Most co-exposed sheep had antibodies against Anaplasma spp./TBEV (n = 36), followed by Anaplasma spp./C. burnetii (n = 27) and Anaplasma spp./C. burnetii/TBEV (n = 2). Only one sheep showed an immune response against C. burnetii and TBEV. Flocks with sheep being positive against more than one pathogen were widely distributed throughout southern Germany. The descriptive analysis revealed no association between the antibody response of the three pathogens at animal level. Taking the flocks as a cluster variable into account, the exposure to TBEV reduced the probability of identifying C. burnetii antibodies in sheep significantly (odds ratio 0.46; 95% confidence interval 0.24–0.85), but the reason for this is unknown. The presence of Anaplasma spp. antibodies did not influence the detection of antibodies against C. burnetii and TBEV. Studies under controlled conditions are necessary to evaluate any possible adverse impact of co-exposure to tick-borne pathogens on sheep health. This can help to clarify rare disease patterns. Research in this field may also support the One Health approach due to the zoonotic potential of Anaplasma spp., C. burnetii and TBEV.

ZusammenfassungDie Leptospirose ist eine Zoonose, die bei Mensch und Tier eine große Bandbreite von Krankheitssymptomen mit sehr milden bis hin zu sehr schweren Verläufen aufweisen kann. In Deutschland ist der Labornachweis einer akuten Infektion meldepflichtig: beim Menschen gemäß Infektionsschutzgesetz und bei Schweinen und Schafen gemäß der Verordnung über meldepflichtige Tierkrankheiten. Die Übertragung erfolgt über direkten und indirekten Kontakt mit dem Urin infizierter Tiere, wobei Nagetiere als Hauptreservoir gelten. Mit einer durchschnittlichen jährlichen Inzidenz von 0,1 gemeldeten Fällen pro 100.000 Einwohner ist die Leptospirose in Deutschland eine seltene Erkrankung.Im Rahmen des vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Projekts „Verbesserung der Öffentlichen Gesundheit durch ein besseres Verständnis der Epidemiologie nagetierübertragener Krankheiten“ (RoBoPub) werden in diesem Übersichtsartikel aktuelle Kenntnisse zur Leptospirose in Deutschland dargestellt. In einem One-Health-Ansatz werden Informationen zum klinischen Bild, verfügbare Prävalenzdaten bei Mensch und Tier und Erkenntnisse über die Erregerverbreitung, die Wirtsassoziation, die Übertragung des Erregers sowie die Umweltstabilität zusammengefasst. Darüber hinaus werden erste Erkenntnisse zum Einfluss von Populationsschwankungen in Nagetierpopulationen auf das Auftreten der Leptospirose diskutiert. Ziel des Übersichtsartikels ist es, die Wahrnehmung für diese gegenwärtig noch vernachlässigte Erkrankung in Deutschland zu erhöhen.In Zukunft sollten auch die im Zuge des Klimawandels möglicherweise vermehrt auftretenden erhöhten Temperaturen und starken Regenfälle und die damit einhergehende häufigere Exposition des Menschen mit den Erregern berücksichtigt werden.

The raccoon (Procyon lotor) has successfully invaded central Europe, despite the population apparently having been founded by a small number of individuals in two distinct populations in Germany. The ecological success of the invasion has been explained by raccoons being an adaptable, truly omnivorous species. However, the German raccoon population might have a larger number of founders and be more genetically diverse than assumed, as accidental or deliberate releases of household pets or individuals from zoos are relatively common. In the present study, we sequenced a 550-base-pair long fragment of the mitochondrial control region in 193 raccoons from Germany and neighbouring countries. We only identified six different haplotypes; of which, five were limited to Germany. Our results support the notions that the population was founded by a small number of females and that the German raccoons originate from two separate release events in central and eastern Germany. Additionally, however, we provide evidence for the presence of a distinct population in Saxony, eastern Germany. Further studies using different genetic markers are necessary to gain additional information on genetic diversity and population genetic structure.

Francisella tularensis is the aetiological agent of tularemia. Hares, rabbits, and small rodents are the main hosts, but humans can be infected and develop severe clinical symptoms. In Germany, tularemia in humans was a rare disease during the last four decades, but since 2005, this zoonosis seems to be re-emerging. However, only very little is known about the prevalence in the host populations. Therefore, in a study performed from 2006 to 2009, we investigated 2,121 brown hares (Lepus europaeus) and 41 European rabbits (Oryctolagus cuniculus) located in Lower Saxony, Germany for the occurrence of this zoonotic bacterium by PCR and bacterial culture. F. tularensis subsp. holarctica was detected in an average of 1.1% of these animals. Two hot spots were found in northern Lower Saxony indicating outbreaks of tularemia even in hares. This study demonstrates the occurrence of F. tularensis subsp. holarctica within the hare population in Germany. Hunters, medical practitioners, and public health professionals should be aware of the risk which could come from this zoonotic agent especially in the hot spot areas.

Background Tularemia is a zoonotic disease caused by Francisella tularensis that has been found in many different vertebrates. In Germany most human infections are caused by contact with infected European brown hares (Lepus europaeus). The aim of this study was to elucidate the epidemiology of tularemia in hares using phenotypic and genotypic characteristics of F. tularensis. Results Cultivation of F. tularensis subsp. holarctica bacteria from organ material was successful in 31 of 52 hares that had a positive PCR result targeting the Ft-M19 locus. 17 isolates were sensitive to erythromycin and 14 were resistant. Analysis of VNTR loci (Ft-M3, Ft-M6 and Ft-M24), INDELs (Ftind33, Ftind38, Ftind49, RD23) and SNPs (B.17, B.18, B.19, and B.20) was shown to be useful to investigate the genetic relatedness of Francisella strains in this set of strains. The 14 erythromycin resistant isolates were assigned to clade B.I, and 16 erythromycin sensitive isolates to clade B.IV and one isolate was found to belong to clade B.II. MALDI-TOF mass spectrometry (MS) was useful to discriminate strains to the subspecies level. Conclusions F. tularensis seems to be a re-emerging pathogen in Germany. The pathogen can easily be identified using PCR assays. Isolates can also be identified within one hour using MALDI-TOF MS in laboratories where specific PCR assays are not established. Further analysis of strains requires genotyping tools. The results from this study indicate a geographical segregation of the phylogenetic clade B.I and B.IV, where B.I strains localize primarily within eastern Germany and B.IV strains within western Germany. This phylogeographical pattern coincides with the distribution of biovar I (erythromycin sensitive) and biovar II (erythromycin resistance) strains. When time and costs are limiting parameters small numbers of isolates can be analysed using PCR assays combined with DNA sequencing with a focus on genetic loci that are most likely discriminatory among strains found in a specific area. In perspective, whole genome data will have to be investigated especially when terrorist attack strains need to be tracked to their genetic and geographical sources.