Leishmaniosis in dogs and cats

Abstract

Leishmania are vector-borne protozoan parasites. Infection with these parasites can result in a range of clinical diseases, dependent upon the infecting species. Leishmania infantum is the main species causing leishmaniosis in dogs and cats in Europe, as well as visceral and cutaneous forms of leishmaniosis in humans. Dogs are the main reservoir, but cats and other potential vertebrate reservoirs have been also reported. Sand flies (Phlebotomus spp.) are the main vectors, but non-vectorial transmission (e.g. venereal, transplacental) is possible. Lacking a gold-standard diagnostic test, diagnosis of leishmaniosis is achieved mainly based on clinical signs, skin histopathology, serological detection of specific immune responses against Leishmania spp., and molecular detection of the parasite DNA in tissues using polymerase chain reaction. Correct and early diagnosis is essential for timely institution of treatment and for minimising the transmission of Leishmania from infected animals to vectors. Meglumine antimoniate and allopurinol are the most widely used anti-leishmanial drugs, although miltefosine is emerging as a useful alternative to meglumine, especially in the renally-compromised patient. Vaccination to prevent disease is also available, but only for dogs. The advent of effective insecticide-impregnated collars and topical (‘spot-on’) formulations, and insights into the appropriate management of leishmaniosis, lends a hopeful outlook for the future. This article discusses biology, epidemiology, diagnosis, and management of leishmaniosis in dogs and cats, and explains the importance of connecting clinical and research communities in a ‘One Health’ approach for effective surveillance and control of this disease.