First report of Eucoleus boehmi (syn. Capillaria boehmi) in dogs in north-western Italy, with scanning electron microscopy of the eggs

Occurrence of Eucoleus aerophilus in wild and domestic animals: a systematic review and meta-analysis

BACKGROUND

Eucoleus aerophilus (syn. Capillaria aerophila) is a nematode with a worldwide geographical distribution. It causes a disease called lung capillariosis by affecting the respiratory tract of wild and domestic animals, and has also occasionally been described in humans. Despite steady increases in knowledge of the morphology of this neglected parasite, many aspects are still poorly understood. Epidemiological data regarding, for example, geographic distribution, range of hosts, clinical relevance and the actual zoonotic potential of this nematode are scarce and incomplete.

METHODS

This article is a systematic review based on the screening of three databases (PubMed, Web of Science and Science Direct) to identify eligible studies published from 1973 to the end of 2022.

RESULTS

From a total of 606 studies describing the occurrence of E. aerophilus, 141 articles from 38 countries worldwide were included in this meta-analysis, all of which presented results obtained mainly with flotation and necropsy. Due to the occurrence of E. aerophilus in many different species and different matrices (lungs and faeces), we decided to conduct the meta-analysis separately for each species with a given matrix. This systematic review confirmed the status of the Red fox as the main reservoir and main transmitter of E. aerophilus (average prevalence of 43% in faeces and 49% in lungs) and provided evidence of a higher prevalence of E. aerophilus in wild animals in comparison to domestic animals, such as dogs (3% in faeces) and cats (2% in faeces and 8% in lungs). Previous studies have investigated many host-related factors (age, sex, environmental/living conditions) in relation to the prevalence of E. aerophilus, but they show wide variations and no simple relationship has been demonstrates. Furthermore, mixed infections with other pulmonary nematodes, such as Crenosoma vulpis and/or Angiostrongylus vasorum, are reported very frequently, which greatly complicates the diagnosis.

CONCLUSIONS

This systematic review focused on identifying data gaps and promoting future research directions in this area. To the best of our knowledge, this is the first systematic review that evaluates and summarizes existing knowledge on the occurrence and prevalence of E. aerophilus in wild and domestic animals originating from different geographical locations worldwide.

Nematode eggshells: A new anatomical and terminological framework, with a critical review of relevant literature and suggested guidelines for the interpretation and reporting of eggshell imagery

A literature review for a recent ultrastructural study of a trichinelloid eggshell revealed consistently occurring errors in the literature on nematode eggshell anatomy. Examples included nematodes of medical, veterinary, and agricultural importance in several orders. Previous researchers had warned of some of these errors decades ago, but a comprehensive solution was not offered until 2012 when a clarifying new anatomical and developmental interpretation of nematode eggshells was proposed by members of the Caenorhabditis elegans Research Community. However, their findings were explained using arcane acronyms and technical jargon intended for an audience of experimental molecular geneticists, and so their papers have rarely been cited outside the C. elegans community. Herein we (1) provide a critical review of nematode eggshell literature in which we correct errors and relabel imagery in important historical reports; (2) describe common reporting errors and their causes using language familiar to researchers having a basic understanding of microscopy and nematode eggs; (3) recommend a new hexalaminar anatomical and terminological framework for nematode eggshells based on the 2012 C. elegans framework; and (4) recommend new unambiguous terms appropriate for the embryonated/larvated eggs regularly encountered by practicing nematodologists to replace ambiguous or ontogenetically restricted terms in the 2012 C. elegans framework. We also (5) propose a resolution to conflicting claims made by the C. elegans team versus classical literature regarding Layer #3, (6) extend the C. elegans hexalaminar framework to include the polar plugs of trichinelloids, and (7) report new findings regarding trichinelloid eggshell structure.

Efficacy of milbemycin oxime/afoxolaner chewable tablets (NEXGARD SPECTRA®) against Capillaria aerophila and Capillaria boehmi in naturally infected dogs

BACKGROUND

Capillaria aerophila and Capillaria boehmi parasitize the respiratory system of wild and domestic carnivores. Capillaria aerophila inhabits the trachea and bronchi of dogs and cats, while C. boehmi affects the nasal cavities and sinuses of dogs. In dogs the infection may be subclinical or characterized by varying respiratory distress.

METHODS

The present study evaluated the efficacy of an oral formulation containing milbemycin oxime and afoxolaner (NEXGARD SPECTRA^®) in dogs naturally infected with C. aerophila and/or C. boehmi from three enzootic areas of Italy. Dogs were enrolled pending fecal examination and molecular confirmation of respiratory capillarioses. Dogs were allocated in two groups: Group 1 (G1, 25 dogs), treated with a negative control product with no anthelmintic activity (afoxolaner, NEXGARD^®), and Group 2 (G2, 26 dogs), treated with NEXGARD SPECTRA^®. At the day of treatment administration (Day 0), all dogs were clinically examined. Dogs were again subjected to clinical and fecal examinations at Days 28 (± 4) and 56 (± 2). The primary criterion for treatment efficacy was the reduction of fecal Capillaria egg counts in G2 compared with G1. The regression of/recovery from baseline clinical signs was considered as a further efficacy criterion.

RESULTS

Percentage reduction of fecal Capillaria egg counts in the NEXGARD SPECTRA^® group compared to the control group was > 97% on Day 28 and 100% on Day 56, respectively (p < 0.05 for both time points). Twelve of the 13 dogs in the NEXGARD SPECTRA^® group with respiratory signs prior to treatment were free of clinical signs at the end of the study. Conversely, the six control group dogs with respiratory signs prior to treatment remained symptomatic.

CONCLUSIONS

Results of the present study showed that NEXGARD SPECTRA® was safe and highly efficacious in the reduction of C. aerophila and C. boehmi eggs after one treatment with a complete reduction of the egg output after the second administration associated with a recovery from respiratory signs.

New data on eggshell structure of capillariid species: a SEM perspective

Capillariidae is a group of nematode parasites of vertebrates with a complex taxonomy. The structure of the eggshell, which was indicated as the most important characteristic for identification of genus or species through eggs, is very diverse among genera. The visualization and characterization of eggshell by light microscopy (LM) are a challenging task since different planes of the egg surface are needed. Nevertheless, categories of eggshell ornamentation were proposed by LM: smooth, punctuated, reticulated type I, and reticulated type II. The present study aimed to characterize the eggshell structure of Capillariidae species, parasites of mammals and avians, deposited in a helminthological collection using scanning electron microscopy (SEM). Institutional Biological Collections are taxonomic repositories of specimens described and strictly identified at the species level by systematics specialists. SEM eggshell images were obtained from 12 species belonging to 5 genera (Aonchotheca, Baruscapillaria, Capillaria, Echinocoleus, Eucoleus) and compared to their respective LM images. Eggshell patterns observed using SEM were associated categories of eggshell ornamentation previously proposed by LM images. The SEM data indicate that eggshell categories are not in agreement with capillariid genera or sites of infection. However, the study provides previously unknown SEM eggshell information from curated species, which contributes with a specific and supplementary taxonomic feature at the species level of Capillariidae.

An Unusual Case of Mixed Respiratory Capillariosis in a Dog

Nematodes belonging to the genus Capillaria infect a range of domestic and wild animals. Capillaria aerophila and Capillaria boehmi cause respiratory parasitoses in dogs and wild carnivores, e.g., foxes and mustelids, although they are often overlooked in canine clinical practice. The present report describes an unusual case of a severe and mixed infection by C. aerophila and C. boehmi in a privately housed dog that showed acute and life-threatening respiratory and neurological signs. Clinic-pathologic and epizootiological implications are described and discussed.

Capillaria boehmi (syn. Eucoleus boehmi): Challenging treatment of a rarely diagnosed nasal nematode in dogs and high prevalence in Swiss foxes

Despite morphological differences of eggs and adults, Capillaria boehmi infections have been occasionally misdiagnosed as C. aerophila infections in the past. Capillaria boehmi is found in the nasal and paranasal sinuses of wild canids and dogs, which may suffer from nasal discharge, sneezing, epistaxis and, importantly, their scent can be impaired. In this study we present three challenging cases of nasal capillariosis in dogs, report and review the variable success of anthelmintic treatments and investigate C. boehmi prevalence in Swiss red foxes, considered as potential wild life reservoir. Out of two females and one male dog (all scent hounds, aged 3-9 years and weighing 19-31 kg), two dogs were previously coproscopically misdiagnosed with Trichuris infections. Two dogs showed clinical signs such as sneezing, coughing and impaired scent. From one dog adult living C. boehmi were obtained by nasal lavage. The identity of worms and eggs of all three dogs were genetically confirmed (18S rRNA, 100 % identity in 578 base pairs). Dogs 1-3 were followed-up for overall 54, 8, and 67 months, respectively. All dogs repeatedly excreted C. boehmi eggs in faecal samples despite treatments with the following compounds, in various dosage and retreatment protocols: fenbendazole, milbemycin oxime (orally), moxidectin/imidacloprid/ (spot-on) and levamisole (intramuscularly). The different anthelmintic compounds showed variable success regarding their effect on clinical outcome and on stopping egg excretion. Reinfections due to a contaminated environment could not be fully excluded. In winter 2016 and 2017, 218 foxes from the canton of Zurich, Switzerland, were examined. Tissues of nasal and paranasal sinuses were investigated for adult Capillaria specimens and eggs. We describe for the first time C. boehmi infections in Switzerland, observing a high prevalence (190/218, 87.2 %). Overall, 107 of 126 adults (84.9 %, 95 % Confidence Interval, CI: 77.5-90.7 %) and 83 of 92 youngsters (90.2 %, CI: 82.2-95.4 %) were infected. The presence of C. boehmi did not correlate with age (P = 0.209), but correlated significantly with sex: male foxes (102 of 107, 95.3 %, CI: 89.4-98.5 %) were significantly (P = 0.001) more often infected than females (88 of 111, 79.3 %, CI: 70.5-86.4 %). Worm burden ranged from 1 to 72 adult specimens (geometric mean: 5.7). In conclusion, C. boehmi infections can be mis- and/or underdiagnosed in dogs. Appropriate anthelmintic treatments, preventing coprophagia and egg contamination of the surroundings and performing coproscopic controls after treatments are fundamental aspects. Potentially, nasal washing may represent an auxiliary alternative. However, the successful elimination of C. boehmi infections in dogs remains challenging.

Occurrence of canine and feline extra-intestinal nematodes in key endemic regions of Italy

Extra-intestinal nematodes of companion animals are of growing concern in veterinary medicine for their pathogenic potential and the current expansion throughout Europe. The present study has evaluated the occurrence of major canine and feline extra-intestinal nematodes in regions of Italy having epidemiological relevance. Associations of various recorded parameters related to the examined animals have been statistically evaluated, along with a comparative analysis with the most recent epidemiological data. Overall, 1055 dogs and 1000 cats were tested. Among extra-intestinal nematodes Angiostrongylus vasorum was the most common in dogs followed by Capillaria aerophila and Dirofilaria spp.; Aelurostrongylus abstrusus was the most recorded parasite in cats, followed by C. aerophila and Troglostrongylus brevior. The statistical analysis revealed that outdoor access is associated with A. vasorum, A. abstrusus and T. brevior infections, that were also more prevalent in animals with cardio-respiratory signs. Moreover, cats aged less than 12 months had more chances to be infected by lungworms. The data herein presented confirm the occurrence and the possible risk of expansion of different extra-intestinal parasitoses of dogs and cats in Italy, underlining the importance of a constant epidemiologic vigilance and of appropriate control methods.

First morphological and molecular analysis of Eucoleus boehmi like eggs in dogs from Argentina

The canid parasites Eucoleus aerophilus (syn. Capillaria aerophila) and Eucoleus boehmi (syn. Capillaria boehmi) parasitize the lower and the upper respiratory tract, respectively. Reports and descriptions of these nematodes are scarce in Argentina, possibly due to misdiagnosis of morphologically similar trichuroids eggs, and the lack of knowledge about the species of Eucoleus in this geographical area. Scanning electron microscopy is a useful tool for identification of E. boehmi eggs based on the characteristics of the shell structure which differentiate between species. Molecular analysis complements morphological identification. Until now, there are no studies based on the analysis of E. boehmi eggs in Argentina. The aim of the present work was to study by morphological, morphometric, and molecular analysis, eggs attributable to E. boehmi isolated from dogs naturally infected in Mar del Plata city, Argentina. Eggs isolated from two dog fecal samples were analyzed by light and scanning electron microscopy. A fragment of mitochondrial DNA (mtDNA) of the cytochrome c oxidase subunit I gene (cox1) from eggs was sequenced, and phylogenetic analysis was performed in this study. According to morphological results based on the wall surface ultrastructure, the eggs studied were assigned to E. boehmi. Molecular analysis supported the morphological identification. The divergence of 9-12% with the European isolated could suggest a new geographical genetic variation of E. boehmi, but also question the possible existence of cryptic species. This is the first characterization of E. boehmi eggs in dogs from Argentina.

Leishmania infantum, Dirofilaria spp. and other endoparasite infections in kennel dogs in central Italy

Prevalence and risk factors of Leishmania infantum, Dirofilaria spp. and other potentially zoonotic or canine-specific endoparasite infections were assessed in 639 kennel dogs from central Italy. To this end, individual blood and fecal samples were examined using parasitological, immunological and molecular techniques. The presence of compatible clinical pictures, as well as age and gender were considered as putative risks factors. To evaluate risk factors, multivariable analysis with logistic regression and univariable analysis with a Chi square test and a Fischer's exact test were performed. Overall, 52.6% of dogs (95% CI 48.6-56.5) were found positive, while 39.6% of dogs (95% CI 35.8-43.5) were infected by potentially zoonotic species. Leishmania infantum and Dirofilaria repens showed prevalences of 2.5% (95% CI 1.5-4.1) and 2.8% (95% CI 1.7-4.5), respectively. The prevalence of cardiorespiratory parasites was 7.8% (95% CI 5.9-10.3) and included the species Angiostrongylus vasorum, Eucoleus aerophilus, Eucoleus boehmi and D. immitis; the latter showed a prevalence of 0.2% (95% CI 0.001-1). Intestinal parasites were significantly prevalent (38.8%, 95% CI 35-42.7) and they consisted mainly of species of major zoonotic concern, including ancylostomatids, Toxocara canis, Giardia duodenalis, Dipylidium caninum, Taeniidae, Strongyloides stercoralis and Cryptosporidium parvum. Endoparasites were significantly prevalent in clinically suspected dogs. Leishmania infantum and cardiorespiratory nematodes were prevalent in older dogs, while intestinal parasites were prevalent in younger dogs. Results show high dog and public health risks in kennels in central Italy, and suggest the need for more effective control measures.

Host specificity and basic ecology ofMammomonogamus(Nematoda, Syngamidae) from lowland gorillas and forest elephants in Central African Republic

Syngamid strongylids of the genusMammomonogamusundoubtedly belong among the least known nematodes with apparent zoonotic potential and the real diversity of the genus remains hard to evaluate without extensive molecular data. Eggs ofMammomonogamussp. are frequently found in feces of African forest elephants (Loxodonta cyclotis) and western lowland gorillas (Gorilla gorilla gorilla) in Dzanga-Sangha Protected Areas. Using sedimentation-based coproscopic techniques, we found the eggs ofMammomonogamusin 19·7% elephant and 54·1% gorilla fecal samples with 8–55 and 1–24 eggs per gram of fecal sediment for elephants and gorillas, respectively. We used a combination of light microscopy, scanning electron microscopy and analysis of cytochromecoxidase subunit I (cox1) and a partial sequence of 18S rDNA isolated from single eggs to test the hypothesis of possibleMammomonogamusconspecificity in gorillas and elephants. Whereas 18S rDNA sequences were identical in both gorillas and elephants, we distinguished seven different haplotypes within thecox1. Two haplotypes were found in both gorillas and elephants suggesting sharing ofMammomonogamus.Assignment of the parasite toM. loxodontisis proposed. Provided sequences represent the first genomic data onMammomonogamusspp.

Efficacy against nematode infections and safety of afoxolaner plus milbemycin oxime chewable tablets in domestic dogs under field conditions in Europe

Afoxolaner (AFX) plus milbemycin oxime (MO) combination chewable tablets (NexGard Spectra®, Merial) were evaluated for safety and efficacy against naturally acquired nematode infections in domestic dogs in a multi-centre, positive control, blinded field study using a randomized block design based on the order of presentation for allocation. In total, 408 dogs confirmed positive for naturally acquired infections of intestinal nematodes by pre-treatment faecal examination were studied in ten countries in Europe (Albania, Austria, Bulgaria, France, Germany, Hungary, Italy, Lithuania, Romania and Slovakia). Pre-treatment faecal examination revealed Toxocara, Toxascaris, hookworm, Trichuris and/or Capillaria nematode infections in 134, 30, 223, 155 and 14 dogs, respectively. Dogs were allocated to one of two treatment groups in a ratio of 1, AFX + MO chewables (≥2.5 mg AFX + ≥0.5 mg MO per kg body weight, according to dose bands; 207 dogs), and 1, MO plus praziquantel (PRZ) chewables (Milbemax®, Novartis; ≥0.5 mg MO + ≥5 mg PRZ per kg body weight, according to the manufacturer's instructions; 201 dogs) and treated once. For evaluation of efficacy based on reduction of faecal nematode egg counts, two faecal samples, one collected prior to treatment and one collected 9 to 21 days after treatment, were examined using modified McMaster techniques. For evaluation of systemic safety, dogs were examined by a veterinarian before treatment administration and at study end, and dog owners observed the health status of their dogs until the end of the study and reported any abnormal observation. For dogs treated with AFX + MO chewables, the efficacy was 99.7, 99.7, 97.2, 99.7 and 99.7 % for Toxocara, Toxascaris, hookworm, Trichuris and Capillaria, respectively; and the efficacy was 99.5, 99.4, 94.3, 99.9 and 98.0 %, respectively, for the MO + PRZ-treated dogs (p ≤ 0.002 for all nematodes and both treatments). For Toxocara, hookworm and Trichuris, non-inferiority analysis demonstrated that the efficacy of AFX + MO chewable tablets was equal to or better than that of MO + PRZ. In spite that both treatments were ≥98 % efficacious against Toxascaris and Capillaria, a hypothesis of non-inferiority for both genera could not be established due to the low number of dogs infected with these parasites. No treatment-related adverse experiences were observed throughout the study. For both treatments, all dogs were given a systemic safety score of 'excellent' apart from one dog in each treatment group which received a score of 'acceptable'. AFX + MO combination chewables were shown to be safe and demonstrated a high level of efficacy when administered once to dogs infected with a broad range of parasitic nematodes under field conditions.

Eucoleus boehmi infection in red fox (Vulpes vulpes) from Italy

In the last decade an increase of the number of red foxes in anthropized habitats across European countries, including Italy, has been observed. This pones implications in terms of disease transmission between wildlife and domestic animals; in fact, there are evidences of the role of foxes as reservoirs and amplifiers of a broad spectrum of parasites infecting pets. The present study evaluated the prevalence of Eucoleus boehmi, an emerging extra-intestinal nematodes of the Capillariinae subfamily, in red foxes. The nasal passages and sinuses of 179 red foxes culled from several areas of northern and central Italy were inspected and the mucosal surfaces were scrapped and examined for adult nematodes and eggs, microscopically and genetically identified. Overall 55 foxes (30.7%) were found to be infected with E. boehmi, i.e. 27 on inspection of the nasal passages and sinuses and 28 on mucosal flush and scraping. The occurrence of E. boehmi was significantly (p < 0.05) correlated to the sampling location, the age and gender of the animals examined; the higher rates of prevalence were observed in animals culled in Piedmont (43.3%) and in female (60.6%) and adult (38.1%) subjects. A total of 184 adult parasites were recovered, with a mean intensity of infection of 3.34, and a more frequent localization of E. boehmi in the nasal passages rather than in the sinuses. A significant (p < 0.05) relationship was found between the parasite burden and body condition and age of the animals; the intensity of infection was significantly higher in juveniles (mean: 6.3 specimens) and in animals showing poor fox body condition (mean: 7.8 specimens). These results show that E. boehmi is highly prevalent in the red fox populations of certain areas of Italy. Epidemiological implications are discussed, with a special focus on the role that this wild canid may have in the increasing transmission of nasal eucoleosis to domestic dogs.

Red fox (Vulpes vulpes) as a potential reservoir host of cardiorespiratory parasites in Bosnia and Herzegovina

Red fox (Vulpes vulpes) is considered as reservoir of different cardiorespiratory parasites of veterinary and medical importance. Since data on cardiorespiratory parasites in foxes in Bosnia and Herzegovina are still lacking, the aims of the present study were to (i) investigate the prevalence and geographical distribution of these parasites, (ii) determine genetic diversity of detected parasite species, and (iii) to estimate the role of foxes in the transmission cycle to companion animals and humans. Four species, morphologically and molecularly identified as Eucoleus boehmi (64.6%; 51/79), Eucoleus aerophilus (69.7%; 154/221), Crenosoma vulpis (45.7%; 101/221) and Linguatula serrata (1.3%; 1/79) were retrieved from nasal cavity and lungs in 184 (83.3%) animals. The occurrence of heartworms, Angiostrongylus vasorum and Dirofilaria immitis was not detected by necropsy or PCR. Furthermore, three distinct haplotypes of E. aerophilus (I, III, XV) and two of C. vulpis (I, II) previously reported in pet animals and wild carnivores were confirmed in this study. A new haplotype of C. vulpis (designated as haplotype V) was also identified based on 12S rRNA gene for the first time. The present study indicates a high prevalence and wide distribution of nasal and lung nematodes in fox population in Bosnia and Herzegovina, and supports the existence of transmission patterns between wildlife and pet animals.

First report of Eucoleus boehmi infection in a dog from Portugal

Nasal eucoleosis is an uncommonly diagnosed parasitic infection in domestic dogs. Depending on the parasite load, dogs with Eucoleus boehmi may exhibit mild upper respiratory signs such as sneezing and nasal discharge or may not exhibit any clinical signs. The present study describes the case of a 6-year-old male dog, presented with reverse sneezing of 2 months' duration and bilateral nasal serous discharge. The patient had been taking prednisolone for years due to an immune mediated arthritis of the carpal joint. Physical examination, complete blood count, serum chemistry and thoracic radiography were unremarkable. A computed tomography scan of the nasal cavity was compatible with bilateral chronic rhinitis of unknown aetiology. Further investigation by rhinoscopy revealed diffuse erythematous mucosae with several white and serpentine-shaped worms on the turbinates' surface. Morphological identification of the worms collected in situ was performed, revealing filiform nematodes (15-30 mm in length) containing several bipolar plugged and barrel-shaped eggs in their medial segment. The eggs contained a multicellular embryo, a pitted surface and measured 54-60 μm long by 30-35 μm wide. Morphological and morphometric characteristics were consistent with E. boehmi. Treatment with imidacloprid/moxidectin spot-on formulation along with preventing measures to minimise reinfection were prescribed and successfully achieved, as confirmed by negative faecal examinations. To the best of the authors' knowledge, this represents the first report of E. boehmi infection in a dog from Portugal. Nasal eucoleosis appears to be underestimated and should be considered as a differential diagnosis in canids suffering from upper respiratory distress.

PCR-based assay for the mitochondrial cox1 specific amplification of Eucoleus böhmi

Eucoleus böhmi (syn. Capillaria boehmi) is a trichuroid nematode affecting the epithelium of the nasal turbinates, frontal and paranasal sinuses of wild and domestic canids. Knowledge of the geographic distribution of nasal eucoleosis is fragmentary, despite the infection has been described from Europe and North America. Moreover, gaps exist in information available on the importance of the disease in canine clinical practice. The lack of knowledge on E. böhmi is likely due to limitations inherent to diagnostic methodologies. The aim of the present work was to assess a PCR-based assay instrumental to the amplification of a species-specific region of the mitochondrial DNA (mtDNA) gene encoding for the subunit 1 (cox1) gene of E. böhmi. Adult worms of E. böhmi from red foxes and dogs from Norway, Serbia and Italy and individual fecal samples from naturally infected dogs from Italy were included in the study. Stool samples from dogs negative for E. böhmi, but positive for other common parasites in both single and mixed infections, and adult stages of common dog parasites, were used to assess the specificity of this genetic assay. Using the panel of faecal samples, the assay showed a sensitivity of 85.14% and a specificity of 100%.

Intestinal parasites in First World War German soldiers from "Kilianstollen", Carspach, France

Paleoparasitological investigations revealed the presence of intestinal helminths in samples taken from the abdominal cavities of two German soldiers, recovered in the First World War site named “Kilianstollen” in Carspach, France. Eggs from roundworm, whipworm, tapeworm and capillariids were identified. The morphological and morphometrical comparison, followed by statistical analyses, showed that the Carspach capillariid eggs are similar to rodent parasites. Poor sanitary conditions in the trenches, the lack of knowledge of parasites, and the widespread presence of commensal animals, can explain the occurrence of such parasites in human intestines. This study is the second dealing with 20^th century human samples. It confirms the presence of intestinal worms in First World War German soldiers. In this case study, the application of statistics to precise measurements facilitated the diagnosis of ancient helminth eggs and completed the microscopic approach.

Lesions associated with Eucoleus sp. in the non-glandular stomach of wild urban rats (Rattus norvegicus)

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We used histology to examine wild rats for stomach pathology.

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Reactive lesions in the stomach of wild rats were associated with Eucoleus sp.

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Sexually mature and heavy rats had increased odds of infection.

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This represents a substantial host response to parasitism.

Histological lesions associated with Eucoleus sp. infection of the non-glandular stomach were discovered in a wild, urban population of Norway rats (Rattus norvegicus) trapped over a 1-year period in Vancouver, Canada. Four distinct categories of histological lesions in the non-glandular stomach were identified in association with infection in a sample of 183 rats. The apparent prevalence of Eucoleus sp. in the upper gastrointestinal tract (ventral tongue, oropharynx, esophagus and non-glandular stomach) was 43.1% (79/183). Infection with Eucoleus sp. was significantly associated with hyperkeratosis, mucosal hyperplasia, keratin pustules and submucosal inflammation in the non-glandular stomach (P < 0.05). Eucoleus sp. infection and/or related stomach pathology was present in 135/183 (73.8%) of rats. Statistical analysis showed the odds of being affected by Eucoleus sp. or associated stomach pathology were greater in heavier (OR = 1.06, 95% CI = 1.00–1.12) and sexually mature rats (OR = 4.64, 95% CI = 1.23–17.10). Eucoleus sp. infection is common in wild rats in Vancouver and induces substantial host response. The impact of Eucoleus sp. and associated lesions on the health of individual rats and the population as a whole remains to be investigated.

A pilot trial evaluating the efficacy of a 10% imidacloprid/2.5% moxidectin spot-on formulation in the treatment of natural nasal capillariosis in dogs

The efficacy and safety of a spot-on formulation containing 10% imidacloprid and 2.5% moxidectin (Advocate(®), Bayer Animal Health GmbH, Leverkusen, Germany) were evaluated in a pilot trial for the treatment of canine nasal capillariosis caused by Capillaria boehmi (syn. Eucoleus boehmi). Sixteen dogs copromicroscopically positive for C. boehmi eggs were confirmed, either by rhinoscopy or species-specific PCR-coupled sequencing assays, as being affected by nasal capillariosis. The animals were randomly allocated to two different study groups, i.e. one (Group T) treated with Advocate(®) and one (Group C) left untreated, in a ratio of 1:1. The animals underwent clinical examination and quantitative copromicroscopy for C. boehmi eggs on Days -6 and -2 (baseline) and Day 28 ± 2 (post-baseline). Animals in Group T received Advocate(®) on Day 0. On Day 28 ± 2 the efficacy of the treatment (Group T) or the persistence of the infection (Group C) was confirmed by rhinoscopy or, alternatively, by molecular procedures. Seven of the eight dogs in Group T were negative on Day 28 ± 2 (reduction of baseline faecal egg counts by 99.14%), while for one dog a second treatment on Day 28 ± 2 was necessary to clear the infection, as demonstrated on Day 56 ± 2 (reduction of baseline faecal egg counts by 100% in Group T). Seven animals in Group C received a rescue dose of Advocate(®) on Day 28 ± 2 and scored microscopically and molecularly negative for the parasite on Day 56 ± 2, thus increasing the reduction of post-baseline egg counts to 99.57% after a single administration. These promising results show that Advocate(®) spot-on is an effective formulation for the treatment of canine nasal capillariosis under field conditions.

Ribosomal and mitochondrial DNA analysis of Trichuridae nematodes of carnivores and small mammals

Several species of Trichuridae nematodes can infect dogs, cats and wild mammals. The diagnosis of these infections relies on the microscopic identification of eggs which are characterized by a similar "lemon" shape and polar plugs in all Trichuridae. Thus, morphological diagnosis to species level is challenging. The use of biomolecular diagnostic methods is desirable but very little genetic data are known from Trichuridae of carnivores and small mammals. The aim of this work was to genetically characterize several species of Trichuridae that can affect dogs, cats and wild mammals, as a basis to develop molecular diagnostic tests. Specimens (adult worms or eggs) of Eucoleus aerophilus (syn. Capillaria aerophila), Eucoleus boehmi (syn. Capillaria boehmi), Pearsonema plica (syn. Capillaria plica), Aonchotheca putorii (syn. Capillaria putorii), Calodium hepaticum (syn. Capillaria hepatica), Calodium splenaecum (syn. Capillaria splenaeca) and Trichuris vulpis were obtained from carcasses of red foxes, feces of dogs, the liver of a vole and from the spleen of Crocidura sp. Parts of the small subunit rRNA (18S rRNA) gene and of the mitochondrial cytochrome c oxidase subunit I (cox 1 mtDNA) gene were amplified from the above mentioned nematodes, yielding the first 18S rRNA gene sequences of all the capillariid nematodes and the first cox 1 mtDNA sequences of E. boehmi, P. plica, C. hepaticum, A. putorii and T. vulpis. The 18S rRNA gene is highly conserved among the different species and not suitable as a target for specific diagnostic oligonucleotides. However, these sequences contribute to a better understanding of the complex taxonomic relations among Trichuridae. Indeed, a dendrogram based on the 18S rRNA gene locus supports the latest taxonomic revision. Interspecies divergence was much higher at the cox 1 mtDNA gene locus, rendering it suitable for DNA barcoding and particularly valuable in resolving closely related species. Furthermore, the mitochondrial genetic markers defined in the present study are useful to develop Trichuridae species-specific primers.