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

BACKGROUND: The 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. METHODS: Terrestrial 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. RESULTS: Aelurostrongylus 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. CONCLUSIONS: To 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.

Angiostrongylus chabaudi in felids: New findings and a review of the literature.

Cardiopulmonary infections by Angiostrongylus chabaudi affect domestic and wild felids but, due to limited information on the biology of this nematode, its pathogenicity remains unclear. This article describes the histopathological alterations associated with Angiostrongylus infection in a wildcat from Bulgaria, and reviews current literature on this feline angiostrongylid. Nematodes were isolated from lung lavage and faecal samples of a road killed wildcat in Southern Bulgaria. The morphological identification of parasite larvae as A. chabaudi was confirmed by molecular analysis of part of the 18S ribosomal RNA gene. Upon histopathological examination, severe granulomatous pneumonia, ranging from multifocal to coalescing, and pulmonary vascular lesions were observed. Extensive alveolar collapse, alveolar emphysematous changes, parenchymal haemorrhages and small artery wall hyperplasia were observed in the parenchyma adjacent to the granulomas. Histopathological examination revealed the presence of cross-sections of adult female parasites within the lumen of the pulmonary artery branches, the intima altered markedly by subendothelial proliferation and oedematous changes. This study compliments current knowledge of the pathogenesis of feline angiostrongylosis by A. chabaudi in wildcats, as well as of the distribution of this little-known parasite.

Fatal Angiostrongylus dujardini infection in callitrichid monkeys and suricates in an Italian zoological garden.

This paper reports four fatal cases of metastrongylid nematode Angiostrongylus dujardini infection observed in a Saguinus oedipus and a Callimico goeldii monkey and in two suricates (Suricata suricatta). All animals were kept in captivity in a zoo of central Italy. The two monkeys died with no premonitory signs, while the two-month-old suricates showed malaise, anorexia and tachypnea for a few days prior to death. Cardiomegaly and/or granulomatous pneumonia were the major anatomo-pathological findings. Inflammatory lesions were observed in the liver, heart and kidney of the suricates at histology. A. dujardini diagnosis was confirmed through both morphological identification of adult worms recovered at necropsy and molecular characterization of larvae in tissue samples. Callitrichidae and suricates are active predators and maintain their hunting behaviour in captivity and it is then likely that they were exposed to infection by preying on parasitized gastropods, intermediate hosts of A. dujardini, entering zoo enclosures from the surrounding environment. This is the first report of A. dujardini in Italy and in S. suricatta.

Cytological and parasitological analysis of bronchoalveolar lavage fluid for the diagnosis of Angiostrongylus vasorum infection in dogs.

Bronchoalveolar lavage (BAL) is a procedure that retrieves cells and other elements from the lungs for evaluation, which helps in the diagnosis of many pulmonary diseases. The aims of this work were to perform this procedure in dogs in the acute and chronic phases of an Angiostrongylus vasorum infection for cytological analysis and to evaluate the potential of this technique as a diagnostic method for this lung-heart worm. The BAL procedure was performed through the use of an endotracheal tube on seven A. vasorum infected dogs and on five non-infected dogs lined as a control group. Sixty days post-infection (dpi) active and live larvae were retrieved from the bronchoalveolar fluid (BALF) of all infected dogs. Furthermore, in one animal it was possible to retrieve larvae in its BALF before the pre-patent period. This work reports that the A. vasorum infection resulted in an increase of relative neutrophils and eosinophils counts. In contrast, there was a significant decrease in the alveolar macrophage relative count in infected animals from 60 to 330 dpi. This study shows that the BAL is an accurate technique for the diagnosis of canine angiostrongylosis. Moreover, the technique allows us to retrieve cells and other elements that line the lung surface for cytological evaluation, which provides information about inflammatory diseases, and the diagnosis and prognosis of pulmonary parasites such as A. vasorum.

Interleukin-5 transgenic mice show augmented resistance to Angiostrongylus costaricensis infection.

To determine the possible role of eosinophils in Angiostrongylus costaricensis infection, both interleukin-5 (IL-5) transgenic (Tg) and non-transgenic (non-Tg) C3H/HeN mice were infected with A. costaricensis third-stage larvae. IL-5 Tg mice demonstrated greater resistance than non-Tg mice to A. costaricensis, as shown by lower adult worm recovery, smaller adults, fewer eggs in the intestinal wall and fewer larvae passed in the feces. Both mice showed similar antigen-specific IgA and IgGI antibody responses, although IgA was more prominent than IgG1. Egg deposition and inflammatory responses in the intestinal walls were milder in IL-5 Tg mice than in non-Tg mice. The eggs with developed larvae, deposited in the intestinal walls of IL-5 Tg mice, were surrounded by numerous degranulating eosinophils and sometimes with Splendore-Hoeppli deposits. The data suggest that eosinophils are involved in the resistance of the mouse during primary infection with A. costaricensis.