Felid Cardiopulmonary Nematodes: Dilemmas Solved and New Questions Posed

Abstract

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.

Parasites of the Reintroduced Iberian Lynx (Lynx pardinus) and Sympatric Mesocarnivores in Extremadura, Spain

“…No L1 of lungworms nematodes were detected in the Iberian lynx and mesocarnivores, even though previous studies have reported Aelurostrongylus abstrusus, Oslerus rostratus, Angiostrongylus chabaudi, and nematodes of the genus Troglostrongylus in wild/domestic cats and other wild Felidae species [30]. A. abstrusus was previously recorded in the Eurasian lynx (Lynx lynx) with a prevalence of 17% [31].…”

Endoparasites of European Wildcats (Felis silvestris) in Greece

“…The cat lungworm A. abstrusus has been described in many wild felid species, though confirmed cases are few [ 7 , 80 ]. This parasite unequivocally infects European wildcats, as proven by epizootiological surveys and case reports [ 11 , 12 , 23 ].…”

“…This additional examination was based either on the recent evidence of taxonomical, biological, and epizotiological unresolved issues for some cardio-respiratory nematodes, as for Angiostrongylus spp., Aelurostrongylus abstrusus , Troglostrongylus spp. [ 7 , 13 ], or the necessity to corroborate the microscopic data for poorly known nematodes, such as Cylicospirura spp.…”

“…Other factors threatening this felid species are human-caused mortality (road kills and poisoning) and competition with feral domestic cats for prey and territory [ 2 ]. The interaction with domestic cats in sympatric habitats may also result in disease transmission and both-ways-spill-over of pathogens, such as parasites [ 6 , 7 ]. Parasitism in wild animals is common, and its impact is studied under three perspectives: (i) the effect of infections/infestations on the wild host, (ii) the possibility of transmission and the impact to domestic animals, and (iii) the likelihood of implications on human health [ 8 ].…”

“…Knowledge on parasites affecting European wildcats is scant, due to the elusive nature of these animals and minimum interactions with humans, which render challenging any sample collections. However, in the recent years, the scientific interest on parasites affecting wild felids has increased significantly, as novel insights have shed light on possible bridging infections with cardiopulmonary nematodes between wildcats and domestic cats [ 7 , 11 , 12 , 13 , 14 ]. Recent data have suggested that domestic cats in Greece may be infected by parasites and vector-borne pathogens, which could be shared by wildcats and in some cases have the potential to also infect dogs and humans [ 15 , 16 , 17 , 18 , 19 , 20 , 21 ].…”