Lyme borreliosis caused by spirochetes of the Borrelia burgdorferi (sensu lato) complex is still the most common tick-borne disease in Europe, posing a considerable threat to public health. The predominant vector in Europe is the widespread hard tick Ixodes ricinus, which also transmits the relapsing fever spirochete B. miyamotoi as well as pathogenic Rickettsiales (Anaplasma phagocytophilum, Rickettsia spp.). To assess the public health risk, a long-term monitoring of tick infection rates with the named pathogens is indispensable. The present study is the first German 10-year follow-up monitoring of tick infections with Borrelia spp. and co-infections with Rickettsiales. Furthermore, a specific Reverse Line Blot (RLB) protocol for detection of B. miyamotoi and simultaneous differentiation of B. burgdorferi (s.l.) geno-species was established. Overall, 24.0% (505/2100) of ticks collected in the city of Hanover were infected with Borrelia. In detail, 35.4% (203/573) of adult ticks [38.5% females (111/288) and 32.3% males (92/285)] and 19.8% nymphs (302/1527) were infected, representing consistent infection rates over the 10-year monitoring period. Geno-species differentiation using RLB determined B. miyamotoi in 8.9% (45/505) of positive ticks. Furthermore, a significant decrease in B. afzelii and B. spielmanii infection rates from 2010 to 2015 was observed. Co-infections with Rickettsia spp. and A. phagocytophilum increased between 2010 and 2015 (7.3 vs 10.9% and 0.3 vs 1.1%, respectively). Long-term monitoring is an essential part of public health risk assessment to capture data on pathogen occurrence over time. Such data will reveal shifts in pathogen geno-species distribution and help to answer the question whether or not climate change influences tick-borne pathogens.

Toxocara canis and Toxocara cati, the worldwide occurring intestinal roundworms of canids and felids, represent an important public health threat due to various disease manifestations in humans. Host recognition of pathogens is mediated by pattern recognition receptors (PRRs). Myeloid C-type lectin receptors (CLRs) are PRRs and recognise carbohydrate structures of various pathogens. As Toxocara excretory-secretory products (TES) are predominantly composed of glycoconjugates, they represent suitable targets for CLRs. However, the range of host-derived CLRs recognising Toxocara spp. is still unknown. Using a CLR-hFc fusion protein library, T. canis and T. cati L3 somatic antigens (TSOM) were bound by a variety of CLRs in enzyme-linked immunosorbent assay (ELISA), while their TES products interacted with macrophage galactose-type lectin-1 (MGL-1). Two prominent candidate CLRs, MGL-1 and macrophage C-type lectin (MCL), were selected for further binding studies. Immunofluorescence microscopy revealed binding of MGL-1 to the oral aperture of L3. Immunoblot experiments identified distinct protein fractions representing potential ligands for MGL-1 and MCL. To evaluate how these interactions influence the host immune response, bone marrow-derived dendritic cell (BMDC) assays were performed, showing MCL-dependent T. cati-mediated cytokine production. In conclusion, MGL-1 and MCL are promising candidates for immune modulation during Toxocara infection, deserving further investigation in the future.

Background: In the last years, research on feline cardio-pulmonary parasites has considerably increased in Europe. Not only domestic cats (Felis catus), but also European wildcats (Felis silvestris) can serve as definitive hosts for these nematodes. The F. silvestris population in Germany has been growing rapidly within the last decades; therefore, the assessment of its cardio-pulmonary parasite status is of importance to unravel whether the wildcat population serves as a substantial reservoir for these nematodes and might pose a health threat to domestic cats. Methods: As part of a nature conservation project for European wildcats in the German federal state Rhineland-Palatinate, lungs (n = 128) and hearts (n = 111) of 128 F. silvestris found dead were examined for cardio-pulmonary parasites. All isolated parasites were identified morphologically, and results were confirmed by molecular analysis of a total of 3–11 specimens of each worm species. Results: A total of 70.3% (90/128) wildcats were positive for at least one lungworm species. Angiostrongylus chabaudi was most common (53.1% [68/128]), followed by Aelurostrongylus abstrusus (42.2% [54/128]), Troglostrongylus brevior (31.3% [40/128]) and Capillaria spp. (3.1% [4/128]). Of note, about two-thirds of the infected wildcats harboured coinfections. Infection intensities ranged from 1 to 167 nematodes per wildcat. Generalised linear models revealed a strong correlation between A. chabaudi and A. abstrusus infection, and prevalences were higher in adult than in younger wildcats, except for T. brevior. Moreover, the T. brevior prevalence varied significantly with nutritional status. Conclusions: This study shows that feline cardio-pulmonary nematodes are common parasites in European wildcats in Germany but do not appear to have a serious impact on the overall health of the population. Due to presumed spillover events via prey, cardio-pulmonary nematodes may circulate between the wildcat population and domestic cats and might therefore pose a health risk to individual domestic cats. Graphical

Sarcoptic mange was detected in five free-ranging raccoon dogs (Nyctereutes procyonoides) in the federal state of Schleswig-Holstein, Germany, during a health assessment study of invasive species, including raccoon dogs, carried out between 2021 and 2022. Four raccoon dogs showed severe lesions, including extensive alopecia with thickening and hyperpigmentation of the skin (lichenification). The fifth animal was less affected, showing only thinning of the hair coat in multiple body locations. Skin scrapings were performed and confirmed the presence of Sarcoptes scabiei. Histopathology of the skin revealed diffuse epidermal hyperplasia and hyperkeratosis, mild eosinophilic dermatitis, and varying amounts of intralesional mites. Staphylococcus pseudintermedius and Corynebacterium auriscanis were detected in the skin samples of the affected animals, indicating a secondary bacterial infection. The source of sarcoptic mange remains unclear; interspecies transmission via direct or indirect contact seems likely. Raccoon dogs are therefore a potential vector for sarcoptic mange, and their behaviour could contribute to disease spread and persistence.

Parasitic infections with gastrointestinal nematodes are a serious problem for the health and welfare of domestic animals and negatively affect the economics of animal production. Haemonchus contortus is a haematophagous nematode of small ruminants responsible for significant mortality and morbidity. In addition, the widespread resistance to synthetic anthelmintic drugs emphasizes the urgent need of alternative treatment options against haemonchosis. This work aims to investigate the anthelmintic activity of an hydroethanolic Combretum mucronatum leaf extract (CMLE) against Haemonchus contortus in goats. Goats were artificially infected with 3500 third-stage larvae of H. contortus, and 21 days later, treated with CMLE (1000, 500, 250 mg/kg) for 4 consecutive days. Different parameters such as faecal egg count reduction, weight and haematocrit were monitored during the experimental period. The number of eggs per gram of faeces (EPG) was concentration-depended lower and significantly reduced compared to the untreated control (p < 0.0001). The effect of the highest CMLE dose (4 ×1000 mg/kg body weight) was similar to the effect of albendazole (1 ×5 mg/kg of body weight). The ED₅₀ and ED₉₀ values calculated were 189.17 and 392.33 mg/kg body weight respectively. ED₅₀ and ED₉₀ values were time-dependent. Moreover, CMLE improved haematocrit and weight of goats in dose-dependent and time-dependent manner. These results showed that CMLE could be used for haemonchosis treatment in small ruminants.

Understanding the impact of parasites on wildlife populations is an important aspect of conservation management. However, research on ectoparasites in wildlife can be difficult, as examinations of live animals which are not habituated to human handling are often impossible. The European wildcat (Felis silvestris) is a strictly protected wildlife species whose population has been recovering in Germany in recent decades. Several studies from different European countries have investigated the parasitological status of European wildcat populations. However, most of these studies assessed endoparasite infections, whereas ectoparasite infestations have often been neglected. To fill this knowledge gap for wildcats in Germany, 131 dead found specimens were examined for ectoparasites by macroscopic and microscopic examination of the fur and the ear canals. Infestation with ectoparasites was present in 84.0% (110/131) of the wildcats. Ticks showed the highest prevalence with 72.5% (95/131) of wildcats infested, with 49.6% (65/131) infested with Ixodes ricinus and 36.6% (48/131) with Ixodes hexagonus/canisuga. A total of 27.5% (36/131) of the wildcats were positive for at least one flea species. Of the nine different flea species identified by morphology and/or molecular analyses, Ceratophyllidae were most common (16.8% [22/131]), with Ceratophyllus sciurorum confirmed on 12.2% (16/131) and Nosopsyllus fasciatus on 1.5% (2/131) animals, followed by Pulex irritans (5.3% [7/131]), Spilopsyllus cuniculi (3.8% [5/131]), Chaetopsylla spp. (3.1% [4/131]) (2/131 Chaetopsylla trichosa and 1/131 Chaetopsylla globiceps), Ctenocephalides felis (1.5% [2/131]), Archaeopsylla erinacei (1.5% [2/131]) and Ctenophthalmus baeticus (0.8% [1/131]). Further, 23.7% (31/131) of the wildcats harboured mites, identified as Trombicula autumnalis in 12.2% (16/131) and Otodectes cynotis in 4.8% (6/124) of cases. The only louse species detected was Felicola hercynianus with a prevalence of 2.3% (3/131). Infestation intensities ranged from 1 to 86 ticks, 1-49 fleas, 1-1896 mites, and 1-92 F. hercynianus per wildcat. This study demonstrates that a variety of ectoparasites infests wildcats in Germany, but they do not seem to have a serious impact on the general health of wildcats, as judged by the hosts' mostly good or very good nutritional condition. In addition, the potential risk to domestic cats (Felis catus) and humans posed by the wildcats' ectoparasites, appears to be low but present.