Canine angiostrongylosis in Italy: occurrence of Angiostrongylus vasorum in dogs with compatible clinical pictures.

This study evaluated the perception of veterinarians in including the emerging metastrongyloid Angiostrongylus vasorum in the differential diagnosis for dogs referred with appropriate signs. Veterinarians at teaching hospitals, private practices or kennels collected faecal samples from 606 symptomatic dogs in six different areas of Italy. The samples were examined with the Baermann technique. Fourteen dogs scored positive for A. vasorum, all showing different clinical pictures, with the most common reason for inclusion in the study being a combination of respiratory signs along with general signs. The most reported sign was cough, followed by aspecific distresses. Other respiratory signs were dyspnoea, tachypnoea and breathing sounds, while bleeding diathesis occurred in one dog. Gastrointestinal disorders were diarrhoea and vomitus, while no neurological signs were detected. Four key cases are herein described, with a special focus on their clinical description, findings at the collateral diagnostic imaging and therapeutic options with moxidectin. This survey provides new data on distribution of A. vasorum in Europe and on the clinical impact of the disease. The results confirm that clinical angiostrongylosis overlaps a series of other conditions of dogs. Awareness among vet practitioners is discussed along with the importance of including A. vasorum on the list of differential diagnoses in canine clinical practice and of performing appropriate diagnostic methods.

Molecular detection of Capillaria aerophila, an agent of canine and feline pulmonary capillariosis.

Capillaria aerophila, a trichuroid nematode causing pulmonary infections in wild and domestic carnivores, is occasionally and potentially poorly recognized in infections of humans due to clinicopathological mimicry and a lack of accurate, robust laboratory diagnostics. The present work evaluated the efficiency of a DNA-based assay amplifying a partial cytochrome c oxidase subunit 1 (cox1) gene of C. aerophila in the diagnosis of lung capillariosis. Fecal samples from 34 dogs and 10 cats positive at parasitological examination for C. aerophila and other endoparasites (i.e., other lungworms, whipworms, roundworms, hookworms, tapeworms, and/or coccidia) and from 44 animals negative for C. aerophila but positive for other endoparasites were molecularly examined. Of the 44 samples positive for C. aerophila at copromicroscopy, 43 scored positive (i.e., 33/34 dogs and 10/10 cats) in seminested PCR, resulting in a sensitivity of 97 to 100%. Samples that were copromicroscopy negative for C. aerophila although positive for other endoparasites never produced a PCR product or nonspecific amplicons. The specific PCR amplification of C. aerophila (i.e., specificity of 100%) was confirmed by a nucleotide sequence analysis of the cox1 amplicons. The potential implications of the molecular diagnosis of lung capillariosis are discussed.

Canine and feline infections by cardiopulmonary nematodes in central and southern Italy.

Capillaria aerophila, Aelurostrongylus abstrusus, Angiostrongylus vasorum and Dirofilaria immitis are cardiopulmonary nematodes affecting dogs and cats and presently emerging in several countries. The results obtained in 2009 - 2010 during a study aiming to investigate the occurrence of these nematodes in regions from Central (Marche and Abruzzo regions--Sites A and B, respectively) and southern (Apulia--Site C) Italy are here reported. A total of 534 and 436 individual faecal samples collected from dogs and cats were examined, together with 471 and 34 faecal environmental samples taken from dog shelters and catteries. One hundred and ninety-two individual blood samples were also collected from dogs. Faeces were examined using copromicroscopical flotations and Baermann technique, whereas blood samples were tested by Knott's method. Eggs of C. aerophila were detected in 1.48 % and 20 % (Site A), 8.67 % and 2.71 % (Site B), and 16.67 % and 0 % (Site C) of individual and environmental canine samples. C. aerophila was found in 2.90 % (Site A), 3.03 % (Site B) and 14.29 % (Site C) of individual cats. Larvae of A. vasorum were found in 0.96 % and 2.48 % of individual and environmental samples from Site B, respectively, while those of A. abstrusus in 1.82 % (Site A) and 9.96 % (Site B) of individual faeces. Microfilariae of Dirofilaria immitis, identified on the basis of key morphological and morphometric features, were detected in 2.56 % of samples collected from Site B. Despite the small sample size, these results indicate that cardiopulmonary nematodes occur in Central and southern Italy, thus they should be included in the differential diagnosis of pet cardiorespiratory diseases. Larger surveys are necessary to gain more information on the diffusion of these parasites, especially for C. aerophila and A. vasorum, for which the actual distribution is poorly known.

New insights into morphological and biological features of Capillaria aerophila (Trichocephalida, Trichuridae).

Capillaria aerophila is a trichuroid nematode affecting the respiratory system of dogs, cats, wild carnivores and, occasionally, humans. Animals become infected by ingesting larvated eggs or earthworms, which act as facultative intermediate hosts. The aim of this work is to present new insights into morphological and biological features of this neglected lungworm. Typical features of C. aerophila eggs, differentiating them from those of most known trichuroid whipworms (i.e. size, asymmetry of bipolar plugs and a wall with a network of anastomosing ridges), were detected upon light and scanning electron microscopy. Eggs of C. aerophila were used for in vitro development. Light microscopy showed typical features of C. aerophila eggs: size, asymmetry of bipolar plugs and a wall with a network of anastomosing ridges. All these features were confirmed upon SEM, in that C. aerophila eggs showed an outer densely striated and net-like shell. Eggs of T. vulpis, used for a comparative analysis, were bigger than those of C. aerophila and showed a thick and smooth wall at both light and scanning electron microscopy. Eggs started to develop after 35 days from shedding and mobile larvae were observed in the eggs after two months. The results of this study provide key information on the biological cycle of C. aerophila and present key morphological characters for the identification of eggs in faeces.

Elusive Angiostrongylus vasorum infections.

BACKGROUND: The parasitic nematode Angiostrongylus vasorum causes severe clinical signs in dogs. The disease is often challenging because infected animals are often presented with clinical signs overlapping those of other diseases. METHODS: The present article describes six angiostrongylosis cases (Cases 1-6) that represent key examples of how canine angiostrongylosis may be extremely confounding. The six animals presented clinical signs compatible with canine angiostrongylosis but they were subjected to clinical examinations for other diseases (e.g. dirofilariosis or immune-mediated disorders) before achieving a correct diagnosis. RESULTS: In Case 1 clinical, radiographic and ultrasound examinations' results resembled a lung neoplasia. Case 2 was a dog with a mixed infection caused by A. vasorum and Dirofilaria immitis. Case 3 was a critically ill dog presented in emergency for an acute onset of dyspnoea caused by lungworm infection. The dog died a few hours after presentation despite support and etiologic therapy. Case 4 was a dog presented for chronic hemorrhages and ecchymoses caused by thrombocytopenia of unknown origin, thought to have an inherited, immune-mediated or infective cause. Case 5 was referred for neurological signs due to a suspected discospondylitis. Case 6 was erroneously diagnosed infected only with D. immitis although the dog was infected only with A. vasorum. A timely administration of an anthelmintic (mostly moxidectin) showed to be effective in treating the infection in those dogs (i.e. Cases 1,2, 4 and 5) that did not suffer with severe lung haemorrhages yet. CONCLUSIONS: Dogs 1-5 were referred in two regions of Italy that are considered non-endemic for A. vasorum. These findings indicate that veterinarians should include angiostrongylosis in the differential diagnosis of cardio-respiratory distress also in non-endemic regions and should perform appropriate diagnostics in the presence of compatible signs even if the clinical picture is atypical.

Field clinical study evaluating the efficacy and safety of an oral formulation containing milbemycin oxime/praziquantel (Milbemax®, Novartis Animal Health) in the chemoprevention of the zoonotic canine infection by Dirofilaria repens.

BACKGROUND: Dirofilaria repens is the causative agent of subcutaneous dirofilariosis of dogs, other animals and humans. This nematode is transmitted by mosquitoes of Aedes, Anopheles and Culex genera. In dogs, the parasite may cause subclinical infection or cutaneous signs. Recently, D. repens has emerged and spread in different geographical areas, with an increase of cases in dogs and humans. Chemoprevention in dogs in endemic areas is the most reliable approach for controlling this infection. This paper describes a randomized, blocked and multicentric clinical field study investigating the efficacy of an oral, chewable formulation containing milbemycin oxime/praziquantel (Milbemax®, Novartis Animal Health) in the chemoprevention of subcutaneous dirofilariosis in dogs. METHODS: This study was conducted in endemic areas of Italy. A total of 249 dogs, at two sites, negative for D. repens, were allocated into two groups (i.e. Treated -T1 vs Untreated-T2) with a ratio of 1:1, and subjected to clinical visits and blood sampling once monthly until the end of the study. All blood samples were microscopically and genetically examined. Animals belonging to T1 group received a minimum target dose of 0.5 mg/kg bodyweight of milbemycin oxime and 5 mg/kg of praziquantel in commercial tablets (Milbemax®) according body weight once every 4 weeks. Animals of group T2 were not treated with Milbemax® but received, when necessary, specific parasiticide treatments. The study duration was 336 ± 2 days for each dog. RESULTS: A total of 219 dogs completed the study (i.e. 111 in T1 and 108 in T2), while 30 dogs (i.e. 13 in T1, 17 in T2) were withdrawn for a variety of reasons unrelated to administration of Milbemax®. The percentages of animals not showing microfilariae of D. repens were 100% (111 animals) in T1 and 94.7% (108 animals out of 114) in group T2. Milbemax® was shown to be safe in treated dogs. CONCLUSIONS: The results of this study confirm that the monthly use of Milbemax® in dogs is effective and safe for the prevention of subcutaneous dirofilariosis in endemic areas.

Mixed trichuroid infestation in a dog from Italy.

BACKGROUND: Capillaria aerophila, Capillaria boehmi and Trichuris vulpis are trichuroid nematodes affecting wild and companion animals all over the World. The canine intestinal whipworm, T. vulpis, is the most common and well- known in veterinary practice, whereas the respiratory C. aerophila and C. boehmi have been rarely reported in pets as a likely consequence of overlapping morphometric and morphological features of the eggs, which impair a correct etiological diagnosis. FINDINGS: In December 2011, a mixed infestation by T. vulpis, C. aerophila and C. boehmi was diagnosed in an asymptomatic dog living in central Italy. Morphometric and morphological findings and pictures of the eggs found at the copromicroscopic analysis are herein reported. CONCLUSIONS: The present work demonstrates that when trichuroid eggs are found in a faecal sample from a dog, a careful morphological and morphometric analysis of individual parasite elements is mandatory. Key diagnostic features (i.e., size, wall surface pattern and aspects of plugs) should be carefully examined when eggs with overlapping shape and appearance are detected. In conclusion, given the importance in clinical practice of canine trichuroids and the zoonotic potential of C. aerophila, these nematodes should be included into the differential diagnosis of intestinal and respiratory parasitoses of dogs by a thorough microscopic analysis of all trichuroid ova present in microscopic fields.

Efficacy of major anthelmintics against horse cyathostomins in France.

This paper reports a survey conducted in France during 2011 to evaluate the efficacy of commonly used anthelmintics against horse cyathostomins. A total of 40 farms and 1089 horses were screened for the presence of cyathostomins. All farms but one were positive, with an overall animal infection rate of 53.7%, ranging from 9% to 83% on individual farms. On 445 horses from 30 of these farms, a faecal egg count reduction test (FECRT) was performed to evaluate the efficacy of oral formulations of fenbendazole (FBZ), pyrantel embonate (PYR), ivermectin (IVM) and moxidectin (MOX). Calculation of the mean FECR and 95% confidence intervals (95% CI) around the mean was performed using bootstrap analysis. Resistance to FBZ was found on 17 of 18 farms investigated, with a mean reduction of 57% (95% CI: 38.5-71.2%). Suspected resistance for PYR was found on 6 of 30 farms, and confirmed on another 3 of 30 farms, with a mean reduction for PYR of 94.7% (95% CI: 88.9-98.5%). Reduced efficacy simultaneously of FBZ and PYR was found in 7 farms. Reduced efficacy of IVM was found in one animal on one farm and of MOX in one animal on another farm, and was combined with resistance against FBZ and/or PYR. These results indicate that single and multiple drug resistance and reduced efficacy in equine cyathostomins is present in France. Macrocylic lactones proved to be highly effective compounds against cyathostomins, with reduced efficacy for IVM and MOX in two farms only. These results extend present knowledge on the occurrence of drug resistant cyathostomins in Europe, and illustrate the necessity to use anthelmintics in appropriate worm control programmes.

Genotyping of Toxoplasma gondii isolates in meningo-encephalitis affected striped dolphins (Stenella coeruleoalba) from Italy.

This study reports the occurrence of Toxoplasma gondii in the brain of three striped dolphins (Stenella ceoruleoalba) found stranded on the Ligurian Sea coast of Italy between 2007 and 2008. These animals showed a severe, subacute to chronic, non-purulent, multifocal meningo-encephalitis, with the cerebral parenchyma of two dolphins harbouring protozoan cysts and zoites immunohistochemically linked to T. gondii. Molecular, phylogenetic and mutation scanning analyses showed the occurrence of Type II and of an atypical Type II T. gondii isolates in one and two dolphins, respectively. In spite of the different molecular patterns characterizing the above T. gondii genotypes, the brain lesions observed in the three animals showed common microscopic features, with no remarkable differences among them. The role of T. gondii in causing the meningo-encephalitis is herein discussed.