Cardiopulmonary Nematode Research Articles

Seek, and you will find: Cryptic diversity of the cardiopulmonary nematode Angiostrongylus vasorum in the Americas

Angiostrongylus vasorum is a metastrongylid parasite infecting wild canids and domestic dogs. Its patchy distribution, high pathogenicity and taxonomical classification makes the evolutionary history of A. vasorum intriguing and important to study. First larval stages of A. vasorum were recovered from feces of two grey foxes, Urocyon cinereoargenteus, from Costa Rica. Sequencing and phylogenetic and haplotypic analyses of the ITS2, 18S and cytochrome oxidase subunit 1 (cox1) fragments were performed. Then p- and Nei´s genetic distance, nucleotide substitution rates and species delimitation analyses were conducted with cox1 data of the specimens collected herein and other Angiostrongylus spp. Cophylogenetic congruence and coevolutionary events of Angiostrongylus spp. and their hosts were evaluated using patristic and phenetic distances and maximum parsimony reconciliations. Specimens from Costa Rica clustered in a separate branch from European and Brazilian A. vasorum sequences in the phylogenetic and haplotype network analyses using the ITS2 and cox1 data. In addition, cox1 p-distance of the sequences derived from Costa Rica were up to 8.6 % different to the ones from Europe and Brazil, a finding mirrored in Nei´s genetic distance PCoA. Species delimitation analysis supported a separate group with the sequences from Costa Rica, suggesting that these worms may represent cryptic variants of A. vasorum, a new undescribed taxon or Angiocaulus raillieti, a synonym species of A. vasorum described in Brazil. Moreover, nucleotide substitution rates in A. vasorum were up to six times higher than in the congener Angiostrongylus cantonensis. This finding and the long time elapsed since the last common ancestor between both species may explain the larger diversity in A. vasorum. Finally, cophylogenetic congruence was observed between Angiostrongylus spp. and their hosts, with cospeciation events occurring at deeper taxonomic branching of host order. Altogether, our data suggest that the diversity of the genus Angiostrongylus is larger than expected, since additional species may be circulating in wild canids from the Americas.

Influence of environmental factors on the occurrence of gastrointestinal and cardiopulmonary nematodes in the red fox in the semi-arid Mediterranean areas of the Iberian Peninsula

Human-induced ecosystem fragmentation is one of the drivers causing wildlife migration from their natural habitats to urban areas, among other reasons. The red fox (Vulpes vulpes) is the most abundant wild canid in the semi-arid Mediterranean areas of the Iberian Peninsula. Water scarcity may result in areas shared by synanthropic fox populations and domestic animals becoming hotspots for parasite transmission. This study describes the gastrointestinal and cardiopulmonary nematode species affecting fox populations in these semi-arid areas and the influence of environmental variables on parasite abundance. A total of 167 foxes collected from 2015 to 2021 in the Region of Murcia (SE Spain) were analysed. Parasite abundance and spatial distribution were evaluated using environmental variables and host characteristics with a Generalised Linear Model and the Moran index. Eleven species (seven from the gastrointestinal tract and four from the cardiopulmonary tract) were described. The influence of biotic and abiotic variables was studied for Angiostrongylus vasorum, Crenosoma vulpis, Uncinaria stenocephala, Toxocara canis and Toxascaris leonina. Temperature, humidity and areas of forest or agricultural land influenced the abundance of these parasites, providing optimal conditions for free-living stages of the direct life cycle nematodes and intermediate hosts. Absolute abundance distribution maps showed defined locations for C. vulpis, T. canis and T. leonina. The results for U. stenocephala, T. canis and T. leonina were particularly important as their higher abundance levels were found close to anthropized areas, which need to be carefully evaluated to prevent transmission of these nematodes between domestic and wild canids and human health.

Cardio-pulmonary nematodes of the red fox (Vulpes vulpes) of Sardinia, Italy

Cardio-pulmonary parasites, such as Angiostrongylus vasorum, Crenosoma vulpis, and Eucoleus aerophilus, pose a significant concern on account of pulmonary and cardiac problems they induce in dogs. While the red fox is known to be a key reservoir host for A. vasorum and may also play a role in transmitting C. vulpis and E. aerophilus, there has been no recent research on these parasites in foxes from Sardinia, with the most current studies dating back to 1986. A survey was conducted on red foxes in Sardinia, where a total of 51 foxes were collected, necropsied, and examined for adult worms in their hearts and lungs. The worms were identified using morphometric analysis and molecular methods. The results showed a 54.9% overall prevalence at dissection: 45.1% of the foxes were positive for E. aerophilus, 17.6% for C. vulpis, and 13.7% for A. vasorum. The molecular analyses validated the morphological characterization. In comparison to previous research, which found 13 out of 85 foxes to be positive for A. vasorum with a prevalence rate of 15.3% and 1 for E. aerophilus with a prevalence of 1.2%, this study showed an increased prevalence of E. aerophilus and C. vulpis, and a decrease in the prevalence of A. vasorum. These results indicate that the red foxes in Sardinia represent a reservoir host for cardio-pulmonary nematodes and it should be considered in the differential diagnosis of respiratory distress syndrome in dogs.

What is the sensitivity and exactness of post-mortem diagnostic method for cardiopulmonary nematodes in wild carnivores? towards the gold standard

Cardiopulmonary nematodes cause health and fitness disorders in wild and domestic carnivores. The red fox (Vulpes vulpes) participates in the spread of these shared parasites at the domestic-wildlife interface. This study aimed to evaluate the sensitivity of post-mortem diagnostic method for detecting lungworms in carnivores, and its exactness to estimate the parasite intensity of each nematode species. Cardiorespiratory system of fifty-one foxes were examined through three consecutively methodological steps: first, the tracheobronchial tree, pulmonary arteries and their branches were opened (OT); next, lung parenchyma was immersed in water and squeezed (WS); finally, the parenchyma was artificially digested in a pepsin and chlorhydric acid solution (AD). Eucoleus aerophilus, Angiostrongylus vasorum, Crenosoma vulpis and Metathelazia capsulata were identified. The number of recovered nematodes in each step were 454 (OT), 285 (WS) and 141 (AD). The use of OT and WS helped to improve parasite intensity results and decreased false negative cases. Accordingly, when OT and WS were used together, the sensitivity in the detection of parasitized foxes was 96.1%, while the exactness of parasite intensity was 84%. When AD was performed, although sensitivity does not rise, results were more exact, increasing the total number of detected parasites by 16%. Moreover, AD improved the sensitivity in the detection of A. vasorum and M. capsulata, as well as quantifying more exactly the parasite intensity (92.5% and 92.3% of exactness without AD, respectively). Our study provides valuable information that should be taken into account when planning epidemiological studies based on cardiopulmonary nematode detection in carnivores.

Cardio-pulmonary parasites of the European wildcat (Felis silvestris) in Germany

BackgroundIn 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.MethodsAs 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.ResultsA 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.ConclusionsThis 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 abstract

Is there any change in the prevalence of intestinal or cardiopulmonary parasite infections in companion animals (dogs and cats) in Germany between 2004-2006 and 2015–2017? An assessment of the impact of the first ESCCAP guidelines

Main objective of the present nationwide study was to assess the impact of the ESCCAP guideline for the control of worm infections in dogs and cats 8–10 years after its first publication in Germany. A secondary aim was to determine the prevalence of canine and feline cardiopulmonary nematodes and intestinal protozoa. Faecal samples of 53,693 dogs and 26,491 cats in 2004–2006 as well as of 129,578 dogs and 45,709 cats in 2015–2017 routinely submitted by veterinarians to a private veterinary laboratory were examined using appropriate parasitological methods.In dogs, the prevalence of Toxocara and taeniid egg shedding was significantly lower in 2015–2017 (3.8 % and 0.16 %, respectively) than in 2004–2006 (4.6 % and 0.27 %, respectively). The prevalence of hookworm and Capillaria eggs was higher in the second study period (2.3 % and 0.77 %, respectively) than in the first (1.3 % and 0.6 %, respectively). For Toxascaris leonina (0.55–0.6 %) and Trichuris (0.8–0.9 %), the difference was not significant between the study periods. Dogs shed more often Angiostrongylus vasorum larvae in the second study (3.1 %) than in the first (1.0 %), whereas the prevalence of Crenosoma vulpis did not change significantly (2.2–2.6 %). Cystoisospora canis and C. ohioensis-like infections were less detected in the second study period (1.0 % and 2.1 %, respectively) than in the first (1.8 % and 2.7 %, respectively). Neospora-like oocysts and Sarcocystis sporocysts were more prevalent in the second study period (0.19 % and 0.13 %, respectively) than in the first (0.13 % and 0.06 %, respectively). The percentage of Giardia or Cryptosporidium coproantigen-positive samples was lower in the second study period (18.9 % and 6.7 %, respectively) than in the first (22.8 % and 10.0 %, respectively).In cats, the prevalence of egg shedding of T. cati, Capillaria and taeniids was significantly lower in 2015–2017 (3.5 %, 0.25 % and 0.1 %, respectively) than in 2004–2006 (4.8 %, 0.54 % and 0.22 %, respectively). No difference was recorded for hookworms (0.12–0.13 %) and Ts. leonina (0.04–0.05 %). Aelurostrongylus-like larvae were detected more often in the second study period (6.5 %) than in the first (2.6 %). Infections with Cystoisospora felis, C. rivolta, Toxoplasma-like coccids and Sarcocystis were less prevalent in the second study period (1.9 %, 0.7 %, 0.24 % and 0.02 %, respectively) than in the first (2.7 %, 1.1 %, 0.36 % and 0.1 %, respectively). The percentage of Giardia or Cryptosporidium coproantigen-positive samples was significantly lower in the second study period (10.6 % and 4.8 %, respectively) than in the first (15.4 % and 8.3 %, respectively).Although these results indicate a decline of the occurrence of most canine and feline intestinal parasites in Germany over the years, a transmission risk of zoonotic parasites remains. Therefore, the control of helminth infections in domestic dogs and cats continues to be a challenge for veterinarians and pet owners.

A High Prevalence of Cardiopulmonary Worms Detected in the Iberian Wolf (Canis lupus): A Threat for Wild and Domestic Canids.

Simple SummaryThe Iberian wolf (Canis lupus signatus) is a recognized reservoir of some zoonotic parasites that cause diseases transmissible to domestic animals and/or humans. The objective of this study was to determine the diversity of species of cardiopulmonary nematode parasites that affect wolves in northwestern Spain, and to estimate their prevalence and the relationship between these parasites and various epidemiological variables. The cardiopulmonary systems of 57 wolves from Galicia were examined using dissection and cup sedimentation techniques, and the collected worms were then morphologically identified. The overall prevalence of infection by cardiopulmonary nematodes was 24.5%, and the parasite species identified were Angiostrongylus vasorum (19.3%), Crenosoma vulpis (7%) and Eucoleus aerophilus (3.5%). The latter is of zoonotic interest. A significant relationship was found between age and C. vulpis infection, which was only found in animals under one year of age. Our findings indicate that the Iberian wolf could play an important role in maintaining cardiopulmonary parasites in the wild, and they highlight a need to identify potential risks for veterinary and public health.Cardiopulmonary nematodes are highly pathogenic parasites affecting domestic and wild canids. As the result of conservation programs, the Iberian wolf (Canis lupus signatus) population has recently expanded, and its distribution range covers lands from where it had long disappeared. However, the exact epidemiological role of the wolf in the life cycle of zoonotic parasites causing diseases transmissible to pets and/or humans is largely unknown. This study sought to determine the diversity of cardiopulmonary nematode parasite species that affect wolves inhabiting northwestern areas of the Iberian Peninsula, and to estimate their prevalence and the relationship between these parasites and several epidemiological variables. For this purpose, we examined the cardiopulmonary systems of 57 wolves from Galicia (from the provinces A Coruña n = 15, Lugo n = 21, Ourense n =15 and Pontevedra n = 6) using techniques of dissection and cup sedimentation. Collected worms were then identified under a light microscope according to their morphological features. Three species of nematodes were detected: Angiostrongylus vasorum (the “French-heartworm”), Crenosoma vulpis and Eucoleus aerophilus, the latter being of zoonotic interest. The prevalence was 24.5% (14/57; 95% CI 13.3–35.6%) overall, 19.3% for A. vasorum (11/57; 95% CI 8.8–29.2%), 7% for C. vulpis (4/57; 95% CI 0.4–13.6%) and 3.5% for E. aerophilus (2/57; CI −1.1–9.1%). A significant relationship (p = 0.002) was found between age and the presence of C. vulpis, which was only found in juvenile animals. Furthermore, a higher prevalence of A. vasorum and/or C. vulpis was observed in wolves with a lower body condition score (40% and 20%, respectively), though the difference was not significant (p = 0.221 and p = 0.444, respectively). Our findings indicate a high “French-heartworm” and lungworm burden in the wolf population of northern Spain, and they identify a need for studies designed to elucidate the epidemiological role played by the Iberian wolf and to identify possible risks for veterinary and public health.

Nationwide Seroprevalence Survey of Angiostrongylus vasorum-Derived Antigens and Specific Antibodies in Dogs from Colombia.

Angiostrongylus vasorum is a cardiopulmonary nematode, causing several clinical manifestations in dogs, e.g., severe respiratory signs, coagulopathy, and gastrointestinal or neurological signs. In the last decades, this parasite has been described to spread and emerge in Europe and North America. Scant studies on A. vasorum occurrence in South America exist. Recently, A. vasorum was detected in gastropod intermediate hosts in Colombia, where data on definitive host prevalence, e.g., dogs and wild canids, are still limited. Therefore, the sera of 955 dogs, varying in age and breed from seven different departments all over Colombia, were collected and analysed for A. vasorum antigens and parasite-specific antibodies by ELISA. In total, 1.05 % (n = 10; 95 % CI 0.40–1.69) of the samples were antigen-positive and 2.62 % (n = 25; 95 % CI 1.61–3.63) were antibody-positive. These results confirm the presence of A. vasorum in Colombia, although positive results in antigen and antibody reactions in the same dog were not detected. This study is the first large-scale survey on A. vasorum seroprevalences in dogs from Colombia.

Canine cardiopulmonary nematodes in Morocco: Prevalence of Dirofilaria immitis and report of the first autochthonous infection with Angiostrongylus vasorum

Canine cardiopulmonary nematodes in Morocco: Prevalence of Dirofilaria immitis and report of the first autochthonous infection with Angiostrongylus vasorum

New insights into the distribution of cardio-pulmonary nematodes in road-killed wild felids from Romania

BackgroundThe population of wild felids is large and stable in Romania with many carnivore habitats being protected. Felids can be infected with a wide variety of cardio-pulmonary nematodes and can act as reservoirs of infection for domestic cats. The aim of this study was to evaluate the distribution and species diversity of cardio-pulmonary nematodes in wild felids from Romania.MethodsA total of 54 wild felids (7 Lynx lynx and 47 Felis silvestris) were legally collected from different locations in Romania and analysed by complete parasitological necropsy. The entire respiratory tract was longitudinally opened and checked for the presence of nematodes. Detected nematodes were collected and morphologically identified to species level.ResultsTwo Eurasian lynxes and 29 European wildcats were positive for cardio-pulmonary nematodes. Eurasian lynxes were infected with two species of cardio-pulmonary nematodes, Eucoleus aerophilus and Troglostrongylus brevior, while in wildcats the dominant parasite was E. aerophilus (34.0%) followed by Angiostrongylus chabaudi (23.4%) and T. brevior (14.9%). Dirofilaria immitis and Aelurostrongylus abstrusus were each detected in two wildcats (4.3%).ConclusionsThe present study expanded the epidemiological knowledge on felid cardiopulmonary nematodes in Romania. We confirmed the presence of A. abstrusus in wildcats and a patent infection with T. brevior in Eurasian lynx.Graphical

Fox Serum Proteomics Analysis Suggests Host-Specific Responses to Angiostrongylusvasorum Infection in Canids.

Dogs infected with the cardiopulmonary nematode Angiostrongylus vasorum may suffer from respiratory distress and/or bleeding disorders. Descriptions of clinical signs in foxes are rare, despite high prevalence. To evaluate the impact of infection on coagulation and immune response, serum proteins from eight experimentally infected foxes before and after inoculation (day 0, 35, 84, 154) were subjected to differential proteomic analyses based on quantitative data and compared to available data from dogs. The number of proteins with differential abundance compared to the uninfected baseline increased with chronicity of infection. Bone marrow proteoglycan, chitinase 3-like protein 1 and pulmonary surfactant-associated protein B were among the most prominently increased proteins. The abundance of several proteins involved in coagulation was decreased. Enriched pathways obtained from both increased and decreased proteins included, among others, “platelet degranulation” and “haemostasis”, and indicated both activation and suppression of coagulation. Qualitative comparison to dog data suggests some parallel serum proteomic alterations. The comparison, however, also indicates that foxes have a more adequate immunopathological response to A. vasorum infection compared to dogs, facilitating persistent infections in foxes. Our findings imply that foxes may be more tolerant to A. vasorum infection, as compared to dogs, reflecting a longer evolutionary host–parasite adaptation in foxes, which constitute a key wildlife reservoir.

The Angiostrongylus vasorum Excretory/Secretory and Surface Proteome Contains Putative Modulators of the Host Coagulation.

Angiostrongylus vasorum is a cardiopulmonary nematode of canids and is, among others, associated with bleeding disorders in dogs. The pathogenesis of such coagulopathies remains unclear. A deep proteomic characterization of sex specific A. vasorum excretory/secretory proteins (ESP) and of cuticular surface proteins was performed, and the effect of ESP on host coagulation and fibrinolysis was evaluated in vitro. Proteins were quantified by liquid chromatography coupled to mass spectrometry and functionally characterized through gene ontology and pathway enrichment analysis. In total, 1069 ESP (944 from female and 959 from male specimens) and 1195 surface proteins (705 and 1135, respectively) were identified. Among these were putative modulators of host coagulation, e.g., von Willebrand factor type D domain protein orthologues as well as several proteases, including serine type proteases, protease inhibitors and proteasome subunits. The effect of ESP on dog coagulation and fibrinolysis was evaluated on canine endothelial cells and by rotational thromboelastometry (ROTEM). After stimulation with ESP, tissue factor and serpin E1 transcript expression increased. ROTEM revealed minimal interaction of ESP with dog blood and ESP did not influence the onset of fibrinolysis, leading to the conclusion that Angiostrongylus vasorum ESP and surface proteins are not solely responsible for bleeding in dogs and that the interaction with the host’s vascular hemostasis is limited. It is likely that coagulopathies in A. vasorum infected dogs are the result of a multifactorial response of the host to this parasitic infection.

Genome sequence of the cardiopulmonary canid nematode Angiostrongylus vasorum reveals species-specific genes with potential involvement in coagulopathy

Angiostrongylus vasorum is an emerging parasitic nematode of canids and causes respiratory distress, bleeding, and other signs in dogs. Despite its clinical importance, the molecular toolbox allowing the study of the parasite is incomplete. To address this gap, we have sequenced its nuclear genome using Oxford nanopore sequencing, polished with Illumina reads. The size of the final genome is 280 Mb comprising 468 contigs, with an N50 value of 1.68 Mb and a BUSCO score of 93.5%. Ninety-three percent of 13,766 predicted genes were assigned to putative functions. Three folate carriers were found exclusively in A. vasorum, with potential involvement in host coagulopathy. A screen for previously identified vaccine candidates, the aminopeptidase H11 and the somatic protein rHc23, revealed homologs in A. vasorum. The genome sequence will provide a foundation for the development of new tools against canine angiostrongylosis, supporting the identification of potential drug and vaccine targets.

Quantitative proteomics analysis of Angiostrongylus vasorum-induced alterations in dog serum sheds light on the pathogenesis of canine angiostrongylosis

Blood contains hundreds of proteins, reflecting ongoing cellular processes and immune reactions. Infections with the blood-dwelling cardiopulmonary nematode Angiostrongylus vasorum in dogs manifest with a broad spectrum of clinical signs including respiratory distress, bleeding diathesis and neurological signs, and are associated with a perturbed blood protein profile in dogs. However, current knowledge does not completely explain the observed pathologies induced by A. vasorum infections, including bleeding disorders. Using sera from experimentally infected dogs, dog serum proteome was analysed by quantitative mass spectrometry methods over several time points before and after inoculation. Following computational analysis, we identified 139 up- and downregulated proteins after infection (log2 ratio cut-off ≥ 1.0; q-value ≤ 0.05). Among upregulated proteins were chitinase 3-like 1 and pulmonary surfactant-associated protein B (log2 fold-changes ≥ 5). Pathway enrichment revealed the complement (especially the lectin pathway) and coagulation cascades as significantly affected upon analysis of downregulated proteins. Among them were mannan-binding lectin serine peptidases, ficolin, and coagulation factor XIII-B. These results bring new elements towards understanding the underlying pathomechanisms of bleeding diatheses observed in some A. vasorum-infected dogs.

Felid Cardiopulmonary Nematodes: Dilemmas Solved and New Questions Posed.

In the past decade cardiopulmonary nematodes affecting felids have become a core research topic in small animal parasitology. In the late 2000s, an increase in studies was followed by unexpected findings in the early 2010s, which have stimulated research teams to start investigating these intriguing parasites. Prolific scientific debate and exchanges have then fostered field and laboratory studies and epizootiological surveys. New data have improved basic and applied knowledge, solved dilemmas and posed new questions. This article discusses the past and present background to felid cardiopulmonary nematodes after the last few years of intense scientific research. New data which have demonstrated the key role of Aelurostrongylus abstrusus and Troglostrongylus brevior in causing respiratory infections in domestic cats, and on the nil to negligible current importance of other species, i.e., Troglostrongylus subcrenatus, Oslerus rostratus and Angiostrongylus chabaudi, are presented. Biological information and hypothesized alternative routes of infection are analysed and discussed. Novel identification and taxonomical data and issues are reported and commented upon. On the whole, recent biological, ecological and epizootiological information on felid metastrongyloids is critically analysed, with the aim to answer outstanding questions, stimulate future studies, and underline new research perspectives.

Cardiopulmonary nematodes of wild carnivores from Denmark: Do they serve as reservoir hosts for infections in domestic animals?

The cardiopulmonary nematodes Angiostrongylus vasorum, Crenosoma vulpis, Capillaria aerophila and Aelurostrongylus abstrusus, are a cause of concern in the scientific and veterinary community, potentially causing significant disease in domestic animals. To investigate the potential of wild carnivores as reservoir hosts to these parasites, a total of 1041 animals from seven regions of Denmark were sampled: 476 raccoon dogs (Nyctereutes procyonoides), 367 red foxes (Vulpes vulpes), 123 American mink (Neovison vison), 31 beech martens (Martes foina), 30 Eurasian otters (Lutra lutra) and 14 polecats (Mustela putorius). Hearts and lungs were collected and examined for cardiopulmonary parasites. Capillaria aerophila was identified using morphology, whereas A. vasorum and C. vulpis were identified by a duplex real-time PCR, and A. abstrusus by conventional PCR. This is the first Danish report of A. vasorum and C. vulpis infections in raccoon dogs, mink and polecats, and of C. aerophila in raccoon dogs and beech martens. In addition, this is the first time A. vasorum and C. vulpis have been identified in wild animals from the island of Bornholm, just as it is the first report of C. vulpis in American mink, and C. vulpis and A. vasorum in polecats in Europe. The prevalence of A. vasorum appears to have increased in red foxes in Denmark compared to previous studies, while C. vulpis and C. aerophila prevalences are lower. Our data show that several wild carnivores can serve as reservoir hosts for A. vasorum, C. vulpis and C. aerophila in Denmark, and that A. vasorum appears more abundant than previously reported. It is speculated that the A. vasorum increase might relate to increased snail abundance, which may be due to a rise in mean yearly temperatures in Denmark.

Field safety and efficacy of an orally administered combination of sarolaner, moxidectin and pyrantel (Simparica Trio\xae) for the prevention of angiostrongylosis in dogs presented as veterinary patients

BackgroundInfection with the cardiopulmonary nematode Angiostrongylus vasorum may cause severe disease in dogs, therefore prophylactic treatments are necessary to prevent infection in dogs at risk. A clinical field study was conducted to demonstrate the efficacy and safety of an oral combination of sarolaner, moxidectin and pyrantel (Simparica Trio®) for the prevention of A. vasorum infection in dogs (prevention study). A survey study was conducted concurrently to determine the infection pressure in the same areas.MethodsPrevention and survey studies were both conducted at the same veterinary clinics in endemic hot spots for A. vasorum in Denmark and Italy. The prevention study was a randomized, placebo controlled, double masked study where 622 client-owned dogs were treated and tested at 30 days intervals for 10 months. In the survey study 1628 dogs that were at risk of infection and/or were suspected to be infected were tested by fecal and/or serological methods, and the percent of dogs positive for A. vasorum was calculated.ResultsIn the prevention study, there were no adverse events related to treatment with Simparica Trio®. Two placebo-treated animals became infected with A. vasorum during the 10-month study period, while none of the dogs in the combination product-treated group became infected. In the survey study, 12.2% of the study dogs were found positive to A. vasorum, indicating high exposure to the parasite during the period of the prevention study.ConclusionsMonthly oral treatment with the combination of sarolaner, moxidectin and pyrantel (Simparica Trio®) was 100% effective in the prevention of natural infection with A. vasorum in dogs in highly endemic areas. In endemic areas, A. vasorum occurrence in dogs at risk is considerable.

Intermediate gastropod hosts of major feline cardiopulmonary nematodes in an area of wildcat and domestic cat sympatry in Greece

BackgroundThe metastrongyloid nematodes Aelurostrongylus abstrusus, Troglostrongylus brevior and Angiostrongylus chabaudi are cardiopulmonary parasites affecting domestic cats (Felis catus) and wildcats (Felis silvestris). Although knowledge on these nematodes has been improved in the past years, gaps in our knowledge of their distribution and role of gastropods as intermediate hosts in Europe still exist. This study reports on the presence of these nematodes and their intermediate hosts in an area in Greece where domestic cats and wildcats occur in sympatry.MethodsTerrestrial gastropods were collected in the field and identified morphologically and by mitochondrial DNA-sequence analysis. Metastrongyloid larvae were detected by artificial digestion, morphologically identified to the species and stage level and their identity was molecularly confirmed.ResultsAelurostrongylus abstrusus was found in the snails Massylaea vermiculata and Helix lucorum, T. brevior in the slug Tandonia sp., and A. chabaudi in the slug Limax sp. and the snails H. lucorum and M. vermiculata.ConclusionsTo the best of our knowledge this study provides the first reports of (i) terrestrial gastropods being naturally infected with A. chabaudi, (ii) T. brevior naturally infecting terrestrial gastropods in Europe, and (iii) A. abstrusus naturally infecting terrestrial gastropods in Greece. Furthermore, the present study describes for the first time developmental stages of A. chabaudi and T. brevior in naturally infected gastropods. The biological characteristics of various intermediate gastropod hosts that could influence the distribution and expansion of feline cardiopulmonary nematodes are discussed, along with epizootiological implications and perspectives.

Cardiopulmonary nematode infections in wild canids: Does the key lie on host-prey-parasite evolution?

Cardiopulmonary nematodes are among the most pathogenic parasites of domestic and wild canids. The aim of this study was to describe the species diversity, prevalence and infection intensity of these parasites in the Iberian wolf (Canis lupus signatus) and the red fox (Vulpes vulpes) in the northwest of the Iberian Peninsula. 257 foxes and 74 wolves were necropsied between 2008 and 2014. Four nematode species were identified: Angiostrongylus vasorum, Eucoleus aerophilus, Crenosoma vulpis and Filaroides hirthi. This last species was only found in wolves, being the first time that is cited worldwide in this wild canid. The overall parasite prevalence was significantly higher in foxes (70%) than in wolves (28%). Specifically, prevalences in foxes and wolves were, respectively, 43% and 22% for A. vasorum, 33% and 5% for E. aerophilus, and 30% and 9% for C. vulpis. The prevalence of F. hirthi was 16%. The A. vasorum intensity was significantly higher in foxes than in wolves. Differences between host species in the risk of infection would be associated to diverging feeding behavior, and possibly reflects a parasite-host adaptation related to host's hunting strategies and cardiorespiratory requirements. This study revealed an association between infection and environmental factors, and highlighted a wide variation in the spatial distribution of A. vasorum. Our results indicate that cardiopulmonary parasites are widespread in wild canids in northwest Spain, and further agrees with other studies indicating the expansion of A. vasorum in Europe and, therefore, the urgent need to investigate infection in dogs in sympatric areas.

Cardiopulmonary parasitic nematodes of the red fox (Vulpes vulpes) in Serbia.

Among the wild canids, the red fox (Vulpes vulpes) is recognised as an important reservoir species for a range of parasites, including cardiopulmonary nematodes of public health and veterinary importance. As cross-host transmission between the red fox and domestic carnivores can play an important role in the epizootiology of cardiopulmonary parasitic diseases, the aim of the present investigations was to obtain data on the geographical distribution of cardiopulmonary nematodes of the red fox. The material for examination consisted of 83 foxes which were legally hunted at different locations during a three-month period from December 2017 to February 2018. The presence of four emerging species in Europe (Angiostrongylus vasorum, Crenosoma vulpis, Dirofilaria immitis and Eucoleus aerophilus) was revealed in red foxes of Serbia. Crenosoma vulpis and E. aerophilus were detected in foxes in both the plain and the mountainous areas across the country. Dirofilaria immitis is distributed in red foxes near alluvial rivers in Vojvodina province (northern Serbia). Angiostrongylosis caused by A. vasorum was demonstrated to exist in two enzootic foci with a high percentage of infected foxes in a plain area of northern Serbia. To the best of our knowledge, C. vulpis and A. vasorum were discovered for the first time in red foxes in central Serbia. The results provide strong evidence for veterinarians to take into consideration the parasitic nematodes discovered in red foxes in the differential diagnosis of diseases of companion animals. In the context of the 'One Health' approach the results related to the distribution of the zoonotic species E. aerophilus and D. immitis can be useful for medical epidemiology.