New insights on metastrongyloid lungworms infecting cats of Sardinia, Italy

Severe respiratory distress in a stray cat caused by the lungworm Aelurostrongylus abstrusus: A first case report in Lithuania

Aelurostrongylus abstrusus is the most common feline lungworm worldwide. A 4 months old male cat with a history of coughing and dyspnoea was presented to a small animal clinic in Lithuania. Upon clinical examination tachypnoea (64 bpm), cough, stridor, wheezing sound, end-inspiratory crackles, dyspnoea and pulmonary oedema were recorded. Due to suspected bacterial infection and pulmonary oedema, the cat was treated with antibiotics and diuretics for 40 days, without improvement. On week 7 following the first visit, haematology revealed leucocytosis, lymphocytosis, monocytosis and eosinophilia. Thoracic radiographs showed multiple pulmonary alternations. Microscopic examination of bronchoalveolar lavage fluid and faeces (Baermann migration test) confirmed an infection with A. abstrusus by detection of first stage larvae. The cat was treated with spot-on moxidectin/imidacloprid (Advocate® for cats, Elanco Animal Health GmbH) according to manufacturer's instructions. The L1 of A. abstrusus were still present in the faeces 3 weeks, and cough persisted 4 weeks following the first treatment with moxidectin; anthelmintic treatment was therefore continued with a fipronil/praziquantel/eprinomectin spot-on solution (Broadline®; Boehringer Ingelheim/Merial) according to manufacturer's instructions. No L1 of A. abstrusus were present in the faeces 7 weeks and cough disappeared 11 weeks following the first treatment with moxidectin.

Molecular prevalence, phylogenetic characterization, and epidemiological risk factors of pulmonary nematodes in domestic cats in Türkiye

Aelurostrongylus abstrusus, Oslerus rostratus, and Troglostrongylus brevior are nematodes found in the respiratory system of domestic cats and cause a variety of symptoms. All three parasites use the same hosts and niches, and the morphological measurements of their L1s excreted in faeces overlap with each other. In this study, 300 cats brought to Ondokuz Mayıs University Veterinary Teaching Animal Hospital were screened for lungworms by morphological measurements and molecular analyses. The prevalence of the lungworms was found as 1.33% (4/300) for A. abstrusus, 0.66% (2/300) for O. rostratus, and 0.33% (1/300) for T. brevior. Molecular identification of A. abstrusus, T. brevior, and O. rostratus in domestic cats was carried out for the first time in Türkiye within the present study. This study also reveals the risk factors of lungworm positivity in domestic cats in Türkiye.

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.

Metastrongyloid Infection with Aelurostrongylus abstrusus, Troglostrongylus brevior, Oslerus rostratus and Angiostrongylus chabaudi in Feral Cats from the Canary Islands (Spain)

Lungworms are a major cause of feline respiratory disease, frequently underdiagnosed due to its presentation of symptoms being similar to that of other feline respiratory pathologies. Epidemiological data about these nematodes are scarce in the Canary Islands (Spain). Given the veterinary importance of these parasites, the aim of the present study was to improve the current epidemiological knowledge of the lungworm species that could be affecting feral cats in this archipelago. A total of 29 feral cats from La Gomera were analyzed. The respiratory tract of each animal was inspected and the nematodes obtained were identified by morphological keys and molecular techniques. Metastrongylids were detected to be widely distributed throughout the island with a prevalence of 55.2% (16/29). The species Aelurostrongylus abstrusus, Troglostrongylus brevior, Oslerus rostratus and Angiostrongylus chabaudi were identified. Also, coinfections with A. chabaudi and O. rostratus were detected in two animals. The present study shows a high diversity of lungworms in feral cats in La Gomera, with the first report of A. chabaudi and T. brevior for the Canary Archipelago and the first citation of A. chabaudi in cats for Spain. The wide distribution and high prevalence found in this study indicate a high risk of exposure to pulmonary infections in cats.

Prevalence and risk factors associated with cat parasites in Italy: a multicenter study

Background

Parasites that infect cats include protozoa, helminths and arthropods, many of which are transmissible to humans. Effective control relies on a good knowledge of parasite distribution and the risk factors for infection. The present study was aimed at evaluating the prevalence of major feline parasites in Italy and the risk factors associated with their occurrence.

Methods

Over a 12-month study period, feces, hair and ectoparasites from naturally infected cats from feral colonies, shelters and private households were analyzed at 13 study centers across Italy. Samples from these cats (n = 987) were analyzed at all centers using the same diagnostic methods. Prevalence values and risk factors were evaluated statistically for the identification of predictors of risk.

Results

The overall prevalence of gastro-intestinal and broncho-pulmonary (BP) nematodes was 35.9% (354/987). Toxocara cati was the most prevalent species (253/987; 25.6%), followed by Ancylostomatidae (98/987; 9.9%). Among BP nematodes, Aelurostrongylus abstrusus was the most common (76/987; 7.7%). Approximately 35.7% (352/987) of the study population was infested by ectoparasites, of which the most common were fleas (29.4%, 290/987), followed by ear mites Otodectes cynotis (9.8%, 97/987). Predictors of risk for parasite infection included age, a predominantly or exclusively outdoor lifestyle, geographic area and lack of antiparasitic treatment.

Conclusions

Both ecto- and endoparasites are still common in cats throughout Italy, many of them being of zoonotic concern and vectors of pathogens to humans. Given the presence of parasites throughout the entire study period, year-round treatment should be considered. Furthermore, data confirm the need to protect the human–animal bond using proper endo- and ectoparasiticides to reduce the risk of human infection, in application of the One-Health concept.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-04981-2.

Environmental Contamination by Dog Feces in Touristic Areas of Italy: Parasitological Aspects and Zoonotic Hazards

Public spaces are common sites of fecal contamination which is concerning considering the prevalence rates of gastrointestinal pathogens carried by pets. Multiple pet-bound parasite species capable of infecting humans have previously been reported in fecal samples collected from urban areas around the globe, including Italy. In addition, the presence of gastrointestinal parasites has recently been shown in pets from the island of Sardinia, a well-known touristic destination. For these reasons, this study aims to evaluate the level of fecal contamination of two of the most important cities on Sardinia. Furthermore, the presence of endoparasites in fecal samples collected was also investigated to assess the parasitological risks associated with such contamination. A grid approach using a geographical information system was applied, followed by transect counting and sampling. A total of 956 and 220 dog feces with an average feces count of 4.7 and 2.6 per 100 linear meters were found for Sassari and Alghero, respectively. In Sassari 15.6% (52/333) and in Alghero 6.8% (6/88) of the samples tested positive for parasitic elements. Hookworms, Strongyloides stercoralis, Toxocara sp., and Trichuris vulpis were among the parasites most identified. This study showed significant urban contamination of both Sassari and Alghero with dog feces and the parasites within them, including potentially zoonotic species. The general public as well as tourists visiting the island should be aware of the risks associated with this and appropriate measures taken.

Efficacy of a topical combination of eprinomectin, praziquantel, fipronil and (S)-methoprene against developing and adult Troglostrongylus brevior lungworms (Nematoda, Crenosomatidae) in cats

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Broadline® is 100 % effective against Troglostrongylus brevior in cats.

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A treatment has beneficial effects on pathology and health status of the cats.

The efficacy of the eprinomectin, praziquantel, fipronil and (S)-methoprene combination parasiticide Broadline® (Boehringer Ingelheim Animal Health) was evaluated against developing larval and adult stages of Troglostrongylus brevior, a metastrongyloid pulmonary nematode which is reported to parasitize domestic cats in southern Europe with increasing frequency.

Twenty four purpose-bred cats were experimentally infected with 100 third-stage T. brevior larvae each and randomly allocated to either remain untreated (control) or to be treated with the combination product when T. brevior were developing larval (6 days post inoculation, dpi) or adult nematodes (28 dpi) (eight cats per group). Treatments were administered topically at the minimum label dose of 0.12 mL/kg. Fecal samples of the cats were examined to confirm the presence of patent (adult) nematode infections prior to treatment at 28 dpi and to monitor the larval excretion. At necropsy (49 dpi), the weight of the pulmonary lymph nodes and lungs were determined, and T. brevior lungworms were recovered and counted.

All control animals and cats to be treated at 28 dpi excreted T. brevior larvae 24 dpi and 26 dpi while no larvae were excreted by the cats treated at 6 dpi. Following treatment at 28 dpi, T. brevior larval excretion decreased immediatetly and ceased prior to necropsy. Nematode counts demonstrated that treatment with the combination product was 100 % efficacious against both developing larval and adult T. brevior: no lungworms were recovered from any treated cat while all control animals harbored T. brevior (range, 6–52) (p < 0.001).

No treatment-related health problems or any other clinical signs were observed in the cats. However, significantly higher absolute and relative (organ weight to body weight ratio) pulmonary lymph node weights of the control animals compared with the treated cats at 6 dpi (p < 0.001 and p < 0.001, respectively) and at 28 dpi (p = 0.003 and p = 0.019, respectively) indicated the pathology of the T. brevior infection.

In conclusion, the combination product was demonstrated to be 100 % efficacious against developing larval and adult T. brevior. Furthermore, it was demonstrated that indicators of impaired respiratory and immune systems resultant from T. brevior infection can be prevented with an efficacious treatment when administered during the pre-patent period of infection or are improving substantially within three weeks of treatment of cats harboring adult lungworms.

Transmammary transmission of Troglostrongylus brevior feline lungworm: a lesson from our gardens

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Transmammary transmission of Troglostrongylus brevior in domestic cats is suggested.

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Snails, rats and lizards play a role in the epidemiology of this feline lungworm.

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Observational parasitology is important in studying events that may occur in small ecological niches around us.

Feline lungworms such as Aerulostrongylus abstrusus and Troglostrongylus brevior are snail-borne pathogens causing respiratory disease in domestic cats. Paratenic hosts such as rodents and reptiles have also been implicated in the epidemiology of these parasites. Although A. abstrusus has been recognized for a long time as the most prevalent lungworm among cats worldwide, T. brevior is of major concern in kittens. Bearing in mind that disease due to T. brevior occurs mainly in pediatric patients younger than 6 months of age, the diagnosis of this parasite in two kittens presenting severe respiratory disease from the garden of one of the authors inspired us to investigate the potential routes of transmission for T. brevior in domestic cats. Of the three queens (A, B and C) that delivered kittens (n = 8), only cat A was positive for T. brevior, presenting her two kittens severe respiratory clinical signs, which lead to the exitus in one of them, 18 days of age. In addition, three kittens, the offspring of queen B, turned to be positive at the coprological examination after suckling from queen A, whereas those from queen C (that suckled only on their own mother) remained negative. A series of coprological, histological and molecular tests were conducted to confirm the presence of T. brevior in the patients as well as in the other cats cohabiting the same garden. Adult nematodes were retrieved from the trachea and bronchi of the dead kitten (kitten 1A), and larvae at the histology of the lung and liver parenchyma associated with bronco pneumonitis and lymphocytic pericholangitis, respectively. Cornu aspersum (n = 60), Eobania vermiculata (n = 30) snails (intermediate hosts) as well as lizards and rats (potential paratenic hosts) were collected from the same garden and processed through tissue digestion and molecular detection. Troglostrongylus brevior larvae were recovered through tissue digestion from two C. aspersum (3.33 %) and it was confirmed by PCR-sequencing approach, which also detected T. brevior DNA in the liver and lungs of one rat and in the coelomatic cavity of one gecko lizard. During the COVID-19 lockdown, when scientists spent more time at home, we grasp the opportunity to decipher T. brevior biology and ecology starting in a small ecological niche, such as the garden of our house. Data herein presented led us to suggest: i) the transmammary transmission of T. brevior in domestic cats; ii) the role of intermediate and paratenic hosts (including reptiles) in the epidemiology of the infection which they transmit; as well as iii) the importance of observational parasitology in studying any event that certainly occurs in small ecological niches, as it could be in our home gardens.

Molecular Survey of Metastrongyloid Lungworms in Domestic Cats (Felis silvestris catus) from Romania: A Retrospective Study (2008-2011)

Background: Lungworms are recognized as important agents in the pathology of the respiratory system in domestic cats. While Aelurostrongylus abstrusus is worldwide known and studied, Troglostrongylus brevior has gained the attention of the scientific community only in the last decade. The pathogenicity of this species seems to be higher than A. abstrusus, causing more severe clinical presentations and being potentially fatal, especially in young animals. Methods: In this study, 371 DNA isolates of faecal samples were tested by multiplex polymerase chain reaction for the presence of A. abstrusus, T. brevior, and Angiostrongylus chabaudi. Results: The results showed that 30.2% and 6.7% of the investigated domestic cats were positive for A. abstrusus and T. brevior respectively, stressing out the importance of these parasites as agents of respiratory conditions in domestic cats from Romania. None of the samples were positive for A. chabaudi. The age, the outdoor access, and the lack of deworming were identified as significant risk factors for infection with A. abstrusus. Conclusions: This paper represents the first report of T. brevior in domestic cats from Romania. Moreover, it presents the most northern localization in Europe of T. brevior.

Survey of lungworm infection of domestic cats in Hungary

From 61 settlements of 12 Hungarian counties, 303 domestic cats were included in this survey. Between autumn 2016 and spring 2018, fresh faecal samples were randomly collected and examined by flotation and by the Baermann-Wetzel method for the presence of lungworm infection. No eggs of Eucoleus aerophilus were detected. Morphological identification of first instar larvae (L1) was also carried out. In the faeces of 60 cats (19.8%) from 17 settlements and Budapest, L1 of Aelurostrongylus abstrusus were found. More than half of the cats were from the western part of the country. The average number of larvae per gram of faeces was 190.2 ± 304.88. These results are in line with the former findings on the prevalence of aelurostrongylosis of domestic cats in Hungary. In addition, Oslerus rostratus was also found for the first time in the faecal samples of three cats from the eastern part of the country, infected also with Ae. abstrusus. The average age (2.51 ± 1.26 years) of infected cats indicates that lungworm infection is more common among younger cats. No relationship was found between the lung-worm infection and the sex of cats. Non-neutered cats had a significantly higher proportion of lungworm infections. Two-thirds of the infected cats were apparently healthy, and only 19 individuals showed clinical signs of respiratory disorders.

Pulmonary arterial response to Angiostrongylus vasorum in naturally infected dogs: echocardiographic findings in two cases

Background

Angiostrongylus vasorum is a nematode living in the pulmonary arteries of canids. Infected dogs develop severe pulmonary lesions which can potentially lead to pulmonary hypertension (PH). However, reports of PH in natural infected dogs are scant. One of the possible causes of the low prevalence of PH in A. vasorum-infected dogs could be the establishment of large diameter intrapulmonary arteriovenous anastomoses (IPAVAs), which attenuate pulmonary vascular resistance, thus reducing the pulmonary arterial pressure. The present report describes the pulmonary arterial pressure (PAP) response to A. vasorum natural infection in two dogs, assessed by echocardiography and by the saline contrast echocardiographic test (SCE).

Results

Both dogs showed clinical signs of respiratory disease. At presentation, case 1 did not show echocardiographic signs of PH and the SCE test was positive proving the presence of IPAVAs. However, at the follow-up visit, despite A. vasorum infection resolution, the same dog showed PH and the SCE test resulted negative, which ruled out the presence of IPAVAs. Case 2 suffered from severe pulmonary arterial hypertension and right-side congestive heart failure since the day of presentation. Saline contrast echocardiography was negative both at the time of presentation and at the follow-up visit.

Conclusions

In the two cases described above, the PH was not associated with IPAVAs. During A. vasorum infection, IPAVAs recruitment mechanism is able to contrast the rise of PAP until a certain level. It probably represents an initial escape mechanism of PH that, over time, exhausts its compensatory capacities allowing PAP to rise and to be detectable on echocardiography.

Electronic supplementary material

The online version of this article (10.1186/s13071-019-3544-2) contains supplementary material, which is available to authorized users.

Comparison of clinical and imaging findings in cats with single and mixed lungworm infection

OBJECTIVES

This study has compared clinical and imaging features in 52 cats naturally infected by respiratory nematodes Aelurostrongylus abstrusus, Troglostrongylus brevior and Capillaria aerophila, and in both monospecific and mixed infections.

METHODS

Medical records of cats with a lungworm disease were retrospectively reviewed. Cats with clinical examination findings, haematobiochemical analysis and thoracic radiography were included in the study and clinical and radiographic scores were assigned. For eight cats CT of the thorax was also available and analysed. A statistical analysis was performed to investigate the potential correlation between clinical and radiographic score, and to evaluate the effect of age, sex and infection on clinical and radiographic severity.

RESULTS

Monospecific infections by A abstrusus (32/52), T brevior (6/52) and C aerophila (5/52) and coinfections by T brevior/ A abstrusus (7/52), T brevior/ C aerophila (1/52) and A abstrusus/ C aerophila (1/52) were diagnosed. Cats with mixed infections showed higher clinical scores compared with cats with monospecific parasitoses ( P <0.05), while no differences were observed for radiographic scores. No correlation between clinical and radiographic scores was found (rs = 0.50), and these scores were not affected by patient age or sex. CT, performed on cats infected with A abstrusus, T brevior or A abstrusus/T brevior, provided additional information in cats with mild radiographic signs.

CONCLUSIONS AND RELEVANCE

This study indicates that clinical parameters may be more severe in mixed infections than in monospecific parasitoses. A significant correlation between clinical and radiographic score was not detected, while several subclinically infected cats showed radiographic changes. In cats with mild-to-moderate lung patterns, the ventrodorsal/dorsoventral projection showed lesions that are not visible in the lateral projections, especially in the caudal lobes.

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.

One-year parasitological screening of stray dogs and cats in County Dublin, Ireland

To date, there are no recent studies identifying the prevalence of parasites of human and veterinary importance in dogs and cats in Ireland. The interaction between pets and wildlife species in the environment is an important source of parasite exposure to canids and felines, and one likely to be heightened in the stray animal population. This study aimed to establish the prevalence of endoparasites in unowned dogs and cats in County Dublin, Ireland. Feces from stray dogs (n= 627) and cats (n= 289) entering a rehoming centre were collected immediately after defecation. The main parasitic agents detected were ascarids (15.52 and 30.26%),Cystoisospora(3.27 and 3.69%),Giardiaspp. (6.02 and 1.84%) and lungworms (0.64 and 2.08%), in dogs and cats respectively. Animals younger than 3 months of age were more likely to be infected with ascarids (P< 0.001) andCystoisosporaspp. (P= 0.008 andP= 0.014) than older animals. All lungworms were morphologically identified and dogs were infected withAngiostrongylus vasorum(0.48%) andCrenosoma vulpis(0.16%) whereas cats were only infected withAelurostrongylus abstrusus(2.08%). This represents the first prevalence study of stray animals in Ireland. Data collected will inform the treatment and in addition, the future monitoring and control studies of parasite populations.

Feline Troglostrongylosis: Current Epizootiology, Clinical Features, and Therapeutic Options

Parasitic bronchopneumonia plays an important role in feline respiratory medicine, thus it is receiving growing attention by researchers and practitioners. In recent years, Troglostrongylus brevior, a lungworm usually infecting wild felids, has been recognized as an agent of the lower respiratory tract in domestic cats. In particular, as a likely consequence of a spill-over from wild reservoirs (e.g., the European wildcat), T. brevior infection is increasingly reported in cats from Mediterranean and Balkan countries. This parasitic nematode has an indirect life cycle, and its biology overlaps that of the better known "cat lungworm" Aelurostrongylus abstrusus. In fact, cases of co-infections caused by both lungworms are not infrequent in domestic cats. Knowledge on clinical features of troglostrongylosis is still incomplete. Available data indicates that clinical signs and radiographic evidence are severe especially in kittens and young cats, are non-specific and often overlap with those of other feline respiratory diseases, such as feline bronchial disease/asthma, or infectious pneumonia. These characteristics make a definitive diagnosis of troglostrongylosis challenging, this disease requires a timely ancillary therapy and an appropriate anthelminthic treatment. As feline troglostrongylosis is an emerging parasitic disease of domestic cats, it should be included in differential diagnosis for lower respiratory tract disease in cats from regions where this parasite is present but also where it is unexpected. This article reviews current knowledge on the pathogenic role of T. brevior in domestic cats and resulting respiratory illness, with a special focus on clinical aspects, diagnosis, and management of the disease.

Troglostrongylus brevior: a feline lungworm of paediatric concern

The immature immune system of cats in their paediatric age (i.e., first six months of life) favours the establishment of infectious respiratory tract diseases mainly caused by well recognized viruses and bacteria species. Conversely, lungworm infections are less investigated during respiratory disorders in kittens. In the last decade, Troglostrongylus brevior has been found affecting the respiratory tract of cats, along with the better-known Aelurostrongylus abstrusus. Given the scant data available on the epidemiology of feline troglostrongylosis, faecal samples from 575 domestic animals living in three Italian municipalities (i.e., Bari, Messina and Siena) were screened for lungworm infection by Baermann and molecular tecniques. Animals were grouped according to their age as ≤6 months (i.e., paediatric patients), 6-24 months, or >24 months. Paediatric cats were further sub-divided in infant (2-6 weeks), weanling (6-12 weeks) and juvenile (3-6 months). Of the 575 animals tested, 241 (42.0%) were younger than 6 months, 188 (33%) were 6-24-month-old and 146 (25%) were older than 24 months. Lungworm infection was diagnosed in 84 (14.6%) of the examined cats. Of the 49 (20.3%) paediatric animals positive for lungworms, T. brevior was the nematode species most frequently diagnosed (n = 44; 89.8%), followed by A. abstrusus (n = 2; 4.1%), and three cats (6.1%) were co-infected by both species. The diagnosis of T. brevior infection was significantly associated with animals aging ≤6 months (18.2%; P < 0.01) than elder cats. Indeed, the prevalence of infection by T. brevior decreased in animals aging 6-24 months (3.2%) being not detected in cats older than two years. Results of this study indicate that paediatric cats are at higher risk of T. brevior infection compared to adults (P < 0.01).

Troglostrongylus brevior: a new parasite for Romania

Background

The genus Troglostrongylus includes nematodes infecting domestic and wild felids. Troglostrongylus brevior was described six decades ago in Palestine and subsequently reported in some European countries (Italy, Spain, Greece, Bulgaria, and Bosnia and Herzegovina). As the diagnosis by the first-stage larvae (L1) may be challenging, there is a possibility of confusion with Aelurostrongylus abstrusus. Hence, the knowledge on the distribution of this neglected feline parasite is still scarce. The present paper reports the first case of T. brevior infection in Romania. In July 2017, a road-killed juvenile male Felis silvestris, was found in in Covasna County, Romania. A full necropsy was performed and the nematodes were collected from the trachea and bronchioles. Parasites were sexed and identified to species level, based on morphometrical features. A classical Baermann method was performed on the lungs and the faeces to collect the metastrongyloid larvae. Genomic DNA was extracted from an adult female nematode. Molecular identification was accomplished with a PCR assay targeting the ITS2 of the rRNA gene.

Results

Two males and one female nematodes were found in the trachea and bronchioles. They were morphologically and molecularly identified as T. brevior. The first-stage larvae (L1) recovered from the lung tissue and faeces were morphologically consistent with those of T. brevior. No other pulmonary nematodes were identified and no gross pulmonary lesions were observed.

Conclusions

This paper represents the first report of Troglostrongylus brevior infection in Romania, so far representing the second northernmost location for this genus in Europe. The diversity of species infecting wild and domestic felids and the differences regarding the clinical significance of these nematodes highlight the need for a more intense surveillance and proper diagnosis of feline lungworm infections, especially in countries where more species were demonstrated to be present. Furthermore, an increased awareness between clinicians is needed for a correct diagnostic approach to feline lungworm diagnosis.

Occurrence and zoonotic potential of endoparasites in cats of Cyprus and a new distribution area for Troglostrongylus brevior

The present study investigated for the first time the occurrence of pulmonary and intestinal parasites of cats in Cyprus. Cats from five districts of Cyprus (Lefkosia, Lemesos, Larnaka, Pafos and Ammochostos) were examined by classical parasitological methods and the identity of lungworm larvae, whenever present, was confirmed by PCR-coupled sequencing. A total of 185 cats, 48 living exclusively indoors and 137 with outdoor access, were included in the study. Parasites were found in 66 (35.7%) of the examined cats, i.e. Toxocara cati (12%), Cystoisospora rivolta (12%), Joyeuxiella/Diplopylidium spp. (7%), Giardia spp. (6.5%), Troglostrongylus brevior (5%), Cystoisospora felis (2.5%), Aelurostrongylus abstrusus (2%), Taenia spp. (0.5%) and Dipylidium caninum (0.5%). Mixed infections were recorded in 18 cats. Cats that lived exclusively indoors or had received an antiparasitic treatment in the last 6 months were less likely to be infected (p < 0.05). Moreover, cats younger than 1 year old were more likely to shed first-stage larvae of T. brevior (p = 0.04). The present study shows that cats in Cyprus are infected at a high percentage by a variety of parasites that potentially affect their health and also, in some cases (i.e. T. cati, D. caninum, Giardia spp.), may have an impact on human health. Moreover, it was revealed that T. brevior, a lungworm of emerging significance, is present on the island, rendering Cyprus the easternmost distribution border of this parasite in Europe to date.

Single and mixed feline lungworm infections: clinical, radiographic and therapeutic features of 26 cases (2013-2015)

Objectives The aim of this study was to retrospectively describe clinical, radiographic and therapeutic features of feline lungworm infection. Methods Medical records of cats with lungworm diagnosis, thoracic radiography and without concurrent diseases between 2013 and 2015 were reviewed. Collection of data included physical examination, haematology, serum biochemistry, therapy with a variety of anthelmintics and outcomes. Results Thirty-seven records were recovered and 26 were included in the study. Single infections by Aelurostrongylus abstrusus (n = 15), Troglostrongylus brevior (n = 3) and Capillaria aerophila (n = 1) and coinfections by T brevior/ A abstrusus (n = 6) and T brevior/ C aerophila (n = 1) were diagnosed. The most common respiratory signs were coughing (n = 12), increased vesicular sounds (n = 10), dyspnoea (n = 9), such as laboured breathing, orthopnoea or open-mouth breathing, and tachypnoea (n = 6). Two cats were subclinically infected. The most common laboratory abnormality was anaemia (n = 7). Radiographic patterns recorded were interstitial (n = 24), bronchial (n = 21), alveolar (n = 10) and vascular (n = 2). Twenty-five cats had a complete recovery within 2-6 weeks of therapy. One kitten died 7 days after the diagnosis. Conclusions and relevance Lungworms should always be included in the differential diagnosis in cats living in endemic areas and presenting with respiratory signs and radiographic abnormalities. A copromicroscopic examination should be considered as the first diagnostic step for all cats at risk of lungworm infections. In most cases, timely therapy with a variety of anthelmintics guarantees recovery.

Lungworms and gastrointestinal parasites of domestic cats: a European perspective

With the exception of Aelurostrongylus abstrusus, feline lungworms have been poorly studied. Information on their distribution is patchy and mostly limited to case reports. In this study, the occurrence of feline lungworms and co-infecting gastrointestinal parasites has been investigated in 12 European countries (i.e. Austria, Belgium, Bulgaria, France, Greece, Hungary, Italy, Portugal, Romania, Spain, Switzerland and the United Kingdom). An average of 10 domestic cats, with regular outdoor access, was sampled each month for 12months, and freshly passed faeces were collected. Stools were processed using a McMaster assay and a quantitative Baermann-Wetzel method. Animals positive for lungworms and/or gastrointestinal parasites were treated with a formulation containing fipronil, (S)-methoprene, eprinomectin, and praziquantel (Broadline®, Merial), and re-sampled 28days post-treatment. The association between lungworm infection and risk factors was analysed using statistical medians/means and the efficacy of the treatment against each lungworm species was assessed. Of 1990 cats sampled, 613 (30.8%) were positive for at least one parasite, while 210 (10.6%) were infected by lungworms. The prevalence of lungworm infection varied between the sampled sites, with the highest recorded in Bulgaria (35.8%) and the lowest in Switzerland (0.8%). None of the cats from Austria or the United Kingdom were infected by lungworms. Aelurostrongylus abstrusus was the species most frequently detected (78.1%), followed by Troglostrongylus brevior (19.5%), Eucoleus aerophilus (14.8%) and Oslerus rostratus (3.8%). The overall efficacy of the treatment was 99% for A. abstrusus and 100% for T. brevior, O. rostratus and E. aerophilus. Data presented provide a comprehensive account of the diagnosis, epidemiology and treatment of feline lungworms in Europe, as well as of the occurrence of co-infections by gastrointestinal parasites.

Mitochondrial haplotypes of Aelurostrongylus abstrusus and Troglostrongylus brevior (Nematoda, Metastrongyloidea) from domestic and wild felids

The lungworm Aelurostrongylus abstrusus is the most important respiratory parasite of domestic cats. Pulmonary aelurostrongylosis has been reported in wild felids, though unequivocally evidence of wildlife infection by A. abstrusus is scant. Recently, Troglostrongylus brevior, a lungworm usually infecting wild felids, has been described in domestic cats from Mediterranean areas. The present work evaluates the sequence variation of an informative region within the gene encoding the mitochondrial cytochrome c oxidase subunit 1 of A. abstrusus and T. brevior, in order to provide novel information on the genetic make-up of these lungworms. Parasitic stages of A. abstrusus and T. brevior were collected from domestic and wild hosts (i.e., domestic cat, European wildcat, caracal, serval, and lion) from Italy, Greece, and South Africa. Five (HI-HV) and four (HI-HIV) haplotypes were recorded for A. abstrusus and T. brevior, respectively, mostly shared between domestic and wild felids in different geographical areas. The phylogenetic analysis showed that all haplotypes of A. abstrusus and T. brevior clustered as monophyletic groups with a strong nodal support, indicating that all haplotypes identified were distinct from each other. All sequence types represent two distinct species, A. abstrusus and T. brevior, and these genetic convergences are also detected within and among populations of these nematodes, irrespective of their hosts and geographical origin. The occurrence of A. abstrusus and T. brevior haplotypes in different hosts from the same regions and between different countries indicates that the same lungworm populations circulate in domestic and wild hosts under the same routes of transmission.

Respiratory distress associated with lungworm infection in a kitten

CASE SUMMARY

A 5-month-old feral kitten developed worsening respiratory signs, including tachypnea, coughing and wheezing after standard anthelmintic treatment with fenbendazole at a local shelter. The kitten was referred to the University of California, Davis, William R Pritchard Veterinary Medicine Teaching Hospital for further evaluation. Thoracic radiographs revealed a severe diffuse bronchointerstitial pattern with bronchial cuffing, ill-defined nodules and lymphadenomegaly. Differentials included infectious etiologies such as toxoplasmosis, feline infectious peritonitis and cryptococcosis. Parasitic infection was considered less likely, owing to previous anthelmintic treatment. Bronchoalveolar lavage revealed marked neutrophilic and eosinophilic inflammation, and parasitic larvae were observed in a swab of trachea mucus. PCR confirmed the larvae as Aelurostrongylus abstrusus. The kitten recovered with two more rounds of anthelmintic treatment.

RELEVANCE AND NOVEL INFORMATION

Parasitic pneumonia should be considered as a cause of respiratory distress in kittens and cats. Lungworm infections have been more commonly reported in free-roaming young and adult cats, but cannot be excluded as a differential diagnosis in cats from varied environments and in kittens. Kittens appear to be especially sensitive to lungworm infections, manifested by the development of more severe clinical signs; thus lungworm infection should always be considered when presented with a kitten in respiratory distress. In the absence of cytologic confirmation of infection via bronchoalveolar lavage or oropharyngeal swab, PCR provides a valuable means for identification of lungworms, such as A abstrusus and Troglostrongylus brevior.

Relation between Aelurostrongylus abstrusus larvae excretion, respiratory and radiographic signs in naturally infected cats

A study was carried out to assess the possible relation between the number of Aelurostrongylus abstrusus larvae per gram of feces (LPG) with respiratory signs and radiographic findings in naturally infected cats. Out of 196 owned cats, 52 (26.5%) were found infected with A. abstrusus. Positive cats were divided into 4 age groups (1, 2-6 months; 2, 7-11 months; 3, 1-5 years and, 4, >6 years). Thoracic radiographs in double orthogonal views were carried out and cats were ranked on the basis of the respiratory signs (0, no symptoms; 1, mild; 2, moderate and 3, severe symptoms) and radiographic changes. Data showed that increasing LPGs were associated with higher probability to develop more severe symptoms, although some asymptomatic cats had high number of LPGs. Radiographic score and LPGs decreased with increasing cat age. A. abstrusus should be included in the differential diagnosis of lung diseases also in cats with mild respiratory symptoms.

OCCURRENCE OF LUNGWORMS IN EUROPEAN WILDCATS (FELIS SILVESTRIS SILVESTRIS) OF CENTRAL ITALY

The increasing focus on infections in domestic cats ( Felis catus ) has raised questions about lungworm distribution in wild hosts. To enhance knowledge of the occurrence of lungworms in enzootic regions of central Italy, we examined the carcasses of 16 European wildcats ( Felis silvestris silvestris). Adult nematodes, feces, respiratory flushings, and pulmonary tissues were collected at necropsy and then microscopically and genetically analyzed. Fourteen wildcats had single or mixed lungworm species. Aelurostrongylus abstrusus was the most common parasite retrieved, followed by Troglostrongylus brevior. In addition, three specimens of Angiostrongylus chabaudi were found in the pulmonary arteries of one wildcat. Histologically, the most common lesions were a mild-to-severe chronic catarrhal bronchitis and a chronic interstitial pneumonia with smooth muscle hypertrophy, associated with T. brevior and A. abstrusus , respectively. These results demonstrate that the European wildcats may harbor several species of lungworms that may impair their health and welfare. Also, F. s. silvestris is a potential reservoir for respiratory nematodes in domestic cats.

Diagnosis and management of lungworm infections in cats: Cornerstones, dilemmas and new avenues

PRACTICAL RELEVANCE

Respiratory parasites infecting domestic cats are attracting increased attention in feline clinical practice. In addition to the most commonly recognised 'cat lungworm' Aelurostrongylus abstrusus, Troglostrongylus brevior and Capillaria aerophila are now considered important pathogens of the respiratory tract of cats.

GLOBAL IMPORTANCE

These parasites are being increasingly diagnosed in several regions of the world and a continuous update on epidemiological changes and advances in diagnosis and control is of practical importance.

AIMS

This article reviews current knowledge of lungworms affecting cats, with a special focus on recent insights into diagnosis and management of the diseases they cause. The article also explores some potential new avenues for control of feline parasitic respiratory diseases, and highlights some key areas requiring further research.

Troglostrongylus brevior in an Eurasian lynx (Lynx lynx) from Bosnia and Herzegovina

Background

In the past few years the interest of the scientific community on lungworms of the genus Troglostrongylus has grown due to the increased number of unexpected cases of infections with Troglostrongylus brevior in domestic cats from Mediterranean Europe, likely due to a spill-over from wild reservoirs. Thus, there is a merit to increase our knowledge on the occurrence of this parasite in felids from European regions. The present paper describes lung lesions associated with T. brevior infection in the endangered Eurasian lynx (Lynx lynx) from Bosnia and Herzegovina.

Findings

The carcass of an illegally killed 3-year-old male Eurasian lynx was presented for necropsy at the Faculty of Veterinary Medicine of Sarajevo (Bosnia and Herzegovina). Grossly, multiple, multinodular, consolidated and firm, tan to grey areas, occupying the caudal third of caudal lung lobes, were observed. At cut section, the catarrhal fluid was draining from the airways. Larvae of T. brevior were found in tracheal scraping. The histopathological examination revealed multifocal to coalescing areas, centered on bronchi and bronchioles, and expanded alveoli filled with necrotic debris, degenerated inflammatory cells, mostly neutrophils and macrophages, and multiple cross sections of parasite larvae and thin-walled morulated eggs of lungworms. The paraffin-embedded lung samples were molecularly positive for T. brevior.

Conclusion

This paper describes the first record of T. brevior in the Eurasian lynx and the associated host lung pathology. Given its pathogenic potential and the lack of data on troglostrongylosis in lynx populations, the occurrence and impact of Troglostrongylus spp. on wildlife health as well as the role of L. lynx as reservoir of infection for other felids, should be further investigated.

Occurrence of Aelurostrongylus abstrusus and Troglostrongylus brevior in domestic cats in Greece

Background

Despite the evidence that Mediterranean Europe offers suitable conditions for the biology of felid respiratory metastrongyloids, no updated data on the presence of felid lungworms are available for Greece. Although the cat lungworm Aelurostrongylus abstrusus is considered as enzootic in domestic cats (Felis silvestris catus) living in some areas of continental Greece, conversely, Troglostrongylus brevior, has only been reported in the island of Crete. The present study aimed to evaluate the occurrence of Aelurostrongylus abstrusus and Troglostrongylus brevior in domestic cats from four different Greek locations including islands where European wildcats (Felis silvestris silvestris), believed to be the natural reservoir of T. brevior, are considered absent.

Methods

Faeces were collected from 125 stray cats in the city of Athens, and in Crete, Mykonos and Skopelos Islands, and examined by copromicroscopic techniques for the presence of lungworm larvae. When present, larvae were morphologically and molecularly identified.

Results

The occurrence of A. abstrusus and T. brevior was confirmed in 10 (8 %) and 7 (5.6 %) of the samples, respectively. In particular, T. brevior was detected in domestic cats in the city of Athens, and in Mykonos and Skopelos Islands, where wildcats are not present.

Conclusions

This information illustrates that T. brevior may infect domestic cats regardless of the presence of the natural host. Considering the relevant clinical impact of this nematode especially in young animals, it is advisable to include troglostrongylosis in the differential diagnosis of cat respiratory diseases also where this parasite is unexpected.

Felid Lungworms and Heartworms in Italy: More Questions than Answers?

Nematodes infecting the cardiorespiratory system of cats have recently stimulated high scientific interest. Over the past few years, different aspects of these parasites have been clarified and various issues elucidated. This increased knowledge has improved awareness on this topic but, at the same time, some dilemmas have not been solved and new questions have been raised. In this review, we underline and discuss current knowledge of, and new doubts relating to, feline lungworms and heartworms, with the aim of stimulating new studies to fill gaps of basic (i.e., epidemiology and biology) and applied (i.e., clinical aspects) knowledge of the old and new parasites affecting the cardiorespiratory system of cats.

Respiratory nematodes in cat populations of Italy

The occurrence of common respiratory parasites of domestic cats (the metastrongyloid "cat lungworm" Aelurostrongylus abstrusus and the trichuroid Capillaria aerophila) and of neglected respiratory nematodes of felids (Troglostrongylus brevior, Angiostrongylus chabaudi and Oslerus rostratus) was here evaluated in two and three geographical sites of Northern and Central Italy, respectively. In 2014-2015, individual fecal samples of 868 domestic cats were examined microscopically and genetically, and epidemiological data related to parasitic infections were evaluated as possible risk factors by binary logistic regression models. The most common parasite was A. abstrusus in both mono- and poli-specific infections, followed by T. brevior and C. aerophila, while cats scored negative for other parasites. Cats positive for A. abstrusus (1.9-17 % infection rate) and C. aerophila (0.9-4.8 % infection rate) were found in all examined sites, while cats scored positive for T. brevior (1-14.3 % infection rate) in four sites. Also, T. brevior was here found for the first time in a domestic cat from a mountainous area of Northern Italy. The occurrence of lungworms was statistically related to the presence of respiratory signs and more significant in cats with mixed infection by other lungworms and/or intestinal parasites. Cats living in site C of Central Italy resulted statistically more at risk of infection for lungworms than cats living in the other study sites, while animals ageing less than 1 year were at more risk for troglostrongylosis. Finally, the presence of lungworms was more significant in cats with mixed infection by other lungworms and/or intestinal parasites. These results are discussed under epidemiological and clinical points of views.

Metastrongyloid infection by Aelurostrongylus abstrusus, Troglostrongylus brevior and Angiostrongylus chabaudi in a domestic cat

The "cat lungworm", Aelurostrongylus abstrusus, affects cats worldwide. Recently, other cardio-pulmonary parasites, e.g. Troglostrongylus brevior and Angiostrongylus chabaudi, have been isolated from cats either for the first time or a long time after they were first described. This paper describes the first known mixed infection by A. abstrusus, T. brevior and A. chabaudi in a domestic cat. Biological and epidemiological implications of old and "new" metastrongyloid-caused infections in cats are discussed.

Lungworm disease in cats: ABCD guidelines on prevention and management

OVERVIEW

Cardiopulmonary nematodes are emerging parasites of cats in Europe. A number of helminth parasites may be involved. The most prevalent lungworm in domestic cats is Aelurostrongylus abstrusus. Oslerus rostratus and Troglostrongylus species are found mainly in wild cats. The trichurid Capillaria aerophila has a low host specificity and is not uncommon in cats. Additionally the lung flukes Paragonimus species are reported in many species outside of Europe, including cats.

CLINICAL SIGNS

Lungworm infections may be asymptomatic, or cause mild to severe respiratory signs, dependent on the worm species and burden; mixed infections are observed. Kittens can be vertically infected and may develop a more severe disease. Affected cats show a productive cough, mucopurulent nasal discharge, tachypnoea, dyspnoea and, in severe cases, respiratory failure and death.

MANAGEMENT

Early diagnosis and treatment greatly improves the prognosis. First-stage larvae can be easily detected in fresh faecal samples; the Baermann migration method is the enrichment technique of choice, but takes 24 h. Lungworm larvae can be found in tracheal swabs and bronchoalveolar lavage fluid, but with less sensitivity than in faeces. Molecular methods have been developed that exhibit high specificity and sensitivity, and allow diagnosis in the prepatent phase. Treatment options include fenbendazole paste, milbemycin oxime/praziquantel and various spot-on formulations. Severe cases should receive prompt medical care in an intensive care unit.

PREVENTION

Avoiding predation is at present the only preventive measure for pulmonary worms with indirect life cycles.

ZOONOTIC RISK

C aerophila has zoonotic potential, causing severe pulmonary disease in humans. Some Paragonimus species are also of zoonotic concern.

Release of lungworm larvae from snails in the environment: potential for alternative transmission pathways

Background

Gastropod-borne parasites may cause debilitating clinical conditions in animals and humans following the consumption of infected intermediate or paratenic hosts. However, the ingestion of fresh vegetables contaminated by snail mucus and/or water has also been proposed as a source of the infection for some zoonotic metastrongyloids (e.g., Angiostrongylus cantonensis). In the meantime, the feline lungworms Aelurostrongylus abstrusus and Troglostrongylus brevior are increasingly spreading among cat populations, along with their gastropod intermediate hosts. The aim of this study was to assess the potential of alternative transmission pathways for A. abstrusus and T. brevior L3 via the mucus of infected Helix aspersa snails and the water where gastropods died. In addition, the histological examination of snail specimens provided information on the larval localization and inflammatory reactions in the intermediate host.

Methodology/Principal Findings

Twenty-four specimens of H. aspersa received ~500 L1 of A. abstrusus and T. brevior, and were assigned to six study groups. Snails were subjected to different mechanical and chemical stimuli throughout 20 days in order to elicit the production of mucus. At the end of the study, gastropods were submerged in tap water and the sediment was observed for lungworm larvae for three consecutive days. Finally, snails were artificially digested and recovered larvae were counted and morphologically and molecularly identified. The anatomical localization of A. abstrusus and T. brevior larvae within snail tissues was investigated by histology. L3 were detected in the snail mucus (i.e., 37 A. abstrusus and 19 T. brevior) and in the sediment of submerged specimens (172 A. abstrusus and 39 T. brevior). Following the artificial digestion of H. aspersa snails, a mean number of 127.8 A. abstrusus and 60.3 T. brevior larvae were recovered. The number of snail sections positive for A. abstrusus was higher than those for T. brevior.

Conclusions

Results of this study indicate that A. abstrusus and T. brevior infective L3 are shed in the mucus of H. aspersa or in water where infected gastropods had died submerged. Both elimination pathways may represent alternative route(s) of environmental contamination and source of the infection for these nematodes under field conditions and may significantly affect the epidemiology of feline lungworms. Considering that snails may act as intermediate hosts for other metastrongyloid species, the environmental contamination by mucus-released larvae is discussed in a broader context.

Gastropod-borne parasites may cause debilitating clinical conditions in animals and humans. The infection occurs by consumption of intermediate hosts (i.e., snails). However, the ingestion of fresh vegetables contaminated by water and/or snail mucus has been proposed as a transmission source for some zoonotic metastrongyloids (e.g., Angiostrongylus cantonensis). Aelurostrongylus abstrusus and Troglostrongylus brevior cause severe clinical conditions in cats and their prevalence is increasing in feline populations. The epidemiology of feline lungworm infections is poorly understood and the role of gastropod molluscs, as vectors of the disease, is questioned. Since metastrongyloid nematodes may use other little-studied infection pathways, the presence of A. abstrusus and T. brevior larvae was herein assessed in the mucus of Helix aspersa snails and in the water where specimens died. The finding of A. abstrusus and T. brevior infective L3 in the mucus shed by H. aspersa or when infected gastropods die submerged in water indicates that alternative pathways for the transmission of feline lungworms may occur. Accordingly, these results should spur the interest of the scientific community towards the delineation of further infection routes for other metastrongyloids of major human concern, such as Angiostrongylus costaricensis and A. cantonenis.

Efficacy of Broadline® spot-on against Aelurostrongylus abstrusus and Troglostrongylus brevior lungworms in naturally infected cats from Italy

The increasing reports of Aelurostrongylus abstrusus infection and the new information on Troglostrongylus brevior have spurred the interest of the scientific community towards the research of pharmaceutical compounds effective against both pathogens. A novel topical combination of fipronil, (S)-methoprene, eprinomectin and praziquantel (Broadline®, Merial) has been released for the treatment of a variety of feline parasitic infections. The present study reports the efficacy of this spot-on in treating cats naturally infected by feline lungworms. Client owned cats (n=191) were enrolled from three geographical areas of Italy and faecal samples were examined by floatation and Baermann techniques. Twenty-three individuals were positive for L1 of A. abstrusus (n=18) or T. brevior (n=3) or for both species (n=2) and they were topically treated with Broadline®. Seventeen of them were also concomitantly infected by other parasites. Four weeks after treatment, faecal samples were collected and examined to assess the efficacy of a single administration of the product. Based on lungworm larvae counts, the efficacy of the treatment was 90.5% or 100% for A. abstrusus or T. brevior, respectively. Cats released significantly lower amounts of lungworm larvae after treatment compared to pre-treatment (p<0.0001). All but three cats were negative for other nematodes after treatment and all cats recovered from respiratory signs. Results of this study indicate that a single administration of the topical combination fipronil, (S)-methoprene, eprinomectin and praziquantel is effective and safe for the treatment of A. abstrusus and/or T. brevior infections in cats living under field conditions.

Angiostrongylus chabaudi Biocca, 1957: a new parasite for domestic cats?

Background

Natural infection with a species of Angiostrongylus has been reported only once in wildcats from central Italy by Biocca in 1957. The causative species of this infection was identified as Angiostrongylus chabaudi. Following this report, this parasite had never been found in either wild or domestic cats.

Findings

The lungs and the pulmonary arteries of an adult female cat (Felis silvestris catus), road-killed in Sardinia, Italy, were macroscopically examined and dissected under a light microscope for the presence of parasites. A slender nematode was detected and its morphometrical features were consistent with those of A. chabaudi. Morphological data were supplemented by sequencing of the partial cytochrome oxidase c subunit 1 (cox1) gene, as well as the internal transcribed spacer 2 (ITS2) of the rDNA. Nucleotide sequences displayed 99% homology with the ITS2 sequence [GenBank KM216825.1] of a specimen of Angiostrongylus sp. recovered recently from the pulmonary artery of a wildcat in Germany and 91% with cox1 sequence [GenBank GU138118.1] of Angiostrongylus vasorum.

Conclusion

The results of the present study indicate, for the first time, that A. chabaudi may also infect domestic cats, and thus should be considered in the diagnosis of metastrongyloid species infecting their cardio-pulmonary system.

Cardio-Pulmonary Parasitic Nematodes Affecting Cats in Europe: Unraveling the Past, Depicting the Present, and Predicting the Future

Various cardio-pulmonary parasitic nematodes infecting cats have recently been fascinating and stimulating the attention of the Academia, pharmaceutical companies, and veterinary practitioners. This is the case of the metastrongyloids: Aelurostrongylus abstrusus and Troglostrongylus brevior, the trichuroid: Capillaria aerophila (syn. Eucoleus aerophilus), and the filarioid: Dirofilaria immitis. Apparently, these parasites have been emerging in several European countries, thus, gaining an important role in feline parasitology and clinical practice. Under a practical standpoint, a sound knowledge of the biological, epidemiological, and clinical impact of cardio-respiratory parasitoses affecting cats, in addition to a potential risk of introduction, establishment, and spreading of “new” parasites in Europe is mandatory in order to understand the present and future impact for feline medicine and to address new strategies of control and treatment. The purpose of the present article is to review the current knowledge of heartworm and lungworm infections in cats, discussing and comparing past and present issues, and predicting possible future scenarios.

First report of Troglostrongylus brevior in a kitten in Greece

The first case of a natural infestation with Troglostrongylus brevior in a kitten in Greece is described here. A ∼40-day-old stray cat was referred to a private veterinary clinic with signs of respiratory distress. First stage larvae of a metastrongyloid nematode were observed in the wet mount faecal preparation. Despite an anthelmintic treatment, the respiratory signs worsened and the kitten died 2 days later. The larvae in the faeces were identified morphologically and genetically as T. brevior. The present evidence suggests a vertical or direct infestation of the kitten and a severe pathogenic role of T. brevior in young cats. This report expands the recent published cases of troglostrongylosis in domestic cats to a wider geographical distribution and opens new questions on the apparent spreading of T. brevior from wild to domestic hosts.

Feline lungworm Oslerus rostratus (Strongylida: Filaridae) in Italy: first case report and histopathological findings

Oslerus rostratus syn. Anafilaroides rostratus (Strongylida: Filaroididae) is a metastrongyloid transmitted by snails, which localizes in peri-bronchial tissues and in the lung parenchyma of wild as well as domestic cats. In Europe, this nematode has been reported only on two occasions, being diagnosed in cats from Majorca Island and in northern Spain. Here, we describe a case of O. rostratus infection in a necropsied 4-year-old cat in Sicily (southern Italy). At the inspection of lungs, slender and greyish nematodes (four females and two males) were found embedded in the peri-bronchial tissues and in the bronchial walls. Parasites were morphological and molecularly identified as O. rostratus, with their 18S sequences being identical among them and showing a high homology (99%) with those available in public databases. At the histology, nematodes were encapsulated in a pseudo-cystic formation surrounded by an interstitial inflammatory process and fibrous tissue. Lung lesions were mainly represented by peri-luminal fibrosis, hyperplasia and hypertrophy of the bronchial mucosa and glands, respectively. This first record of O. rostratus infection from Italy indicates that this parasite should be included in the differential diagnosis of feline of lungworm infection.

The European wildcats (Felis silvestris silvestris) as reservoir hosts of Troglostrongylus brevior (Strongylida: Crenosomatidae) lungworms

The increasing reports of Troglostrongylus brevior lungworm in domestic cats from Italy and Spain raised questions on its factual distribution and on the role wildcats play as reservoirs of these parasites. Carcasses of 21 wildcats were collected in natural parks of southern Italy (i.e., Catania, Sicily n=5 and Matera, Basilicata n=16) and biometrically and genetically identified as Felis silvestris silvestris, but two as hybrids. Troglostrongylus brevior and Eucoleus aerophilus lungworms were found in 15 (71.4%) and 7 (33.3%) individuals, respectively, being five (23.8%) co-infected by the two species. Both lungworms showed an aggregated distribution in the host population, assessed by k-index (i.e., 0.69 for T. brevior and 0.42 for E. aerophilus). Although no statistical significant difference was recorded among age, gender and geographical location of wildcats, a larger rate of infection by T. brevior was assessed in yearlings (85.7%) than adults (64.3%). This is the first epidemiological study reporting T. brevior infection in the European wildcat and discusses the potential threat this may represent for the conservation of this endangered species of felids. In addition, given the large frequency of lungworm infection herein recorded, the role of wildcats as reservoir hosts of these parasites to domestic cats is discussed.

Parasites of domestic owned cats in Europe: co-infestations and risk factors

BACKGROUND

Domestic cats can be infested by a large range of parasite species. Parasitic infestations may cause very different clinical signs. Endoparasites and ectoparasites are rarely explored in the same study and therefore multiparasitism is poorly documented. The present survey aimed to improve knowledge of the prevalence and risk factors associated with ecto- and endoparasite infestations in owned cats in Europe.

METHODS

From March 2012 to May 2013, 1519 owned cats were included in a multicenter study conducted in 9 veterinary faculties throughout Europe (Austria, Belgium, France, Hungary, Italy, Romania and Spain). For each cat, ectoparasites were checked by combing of the coat surface associated with otoscopic evaluation and microscopy on cerumen samples. Endoparasites were identified by standard coproscopical examinations performed on fresh faecal samples. Risk factors and their influence on parasitism were evaluated by univariate analysis followed by a multivariate statistical analysis (including center of examination, age, outdoor access, multipet status, and frequency of treatments as main criteria) with logistic regression models.

RESULTS

Overall, 50.7% of cats resulted positive for at least one internal or one external parasite species. Ectoparasites were found in 29.6% of cats (CI95 27.3-32.0%). Otodectes cynotis was the most frequently identified species (17.4%), followed by fleas (15.5%). Endoparasites were identified in 35.1% of the cats (CI95 32.7-35.7%), including gastro-intestinal helminths in 25.7% (CI95 23.5-28.0), respiratory nematodes in 5.5% (CI95 4.2-7.0%) and protozoans in 13.5% (CI95 11.8-15.3%). Toxocara cati was the most commonly diagnosed endoparasite (19.7%, CI95 17.8-21.8%). Co-infestation with endoparasites and ectoparasites was found in 14.0% of the cats, and 11.9% harbored both ectoparasites and gastro-intestinal helminths.Age, outdoor access, living with other pets, and anthelmintic or insecticide treatments were significantly associated with the prevalence of various parasites.

CONCLUSIONS

This survey demonstrates that parasitism is not a rare event in European owned cat populations. The prevalence of multi-parasitism is significantly greater than expected by chance and hence there is tendency for some individual cats to be more prone to infestation by both endo- and ectoparasites due to common risk factors.