Canine Leishmaniasis is not easy to diagnose and treat. It is a parasitic pathology, caused by the protozoan Leishmania infantum, which is transmitted to the dog through the bite of an insect, the phlebotomist or sandfly. It looks like a small mosquito, both for its tapered appearance and for the fact that it is a blood-sucking fly.

Leishmania parasites are rather particular because they need both the body of a phlebotomist and that of a mammal such as the dog to develop and multiply: the female of the phlebotomist has to bite the dog and suck its blood in order to lay the eggs. If the dog is infected, Leishmania parasites move into the stomach of the insect where they develop, multiply and become infectious. Thus, when the sand flies bite a healthy dog, parasites are transmitted  through the bite.

Peak-biting activity of phlebotomies is during the warm months, from May to October; the same as mosquitoes, they appearat sunset and are widespread in tropical and sub-tropical areas and throughout the Mediterranean basin, including islands. With the gradual but inexorable increase in the earth’s temperature, sand flies are slowly spreading even in areas with a more temperate climate, such as Northern Italy where there were no outbreaks until a few years ago.

A generalized disease also called viscero-cutaneous form is generally reported in dogs. Infection does not always lead to disease, in fact many infected dogs remain asymptomatic for life, without developing clinical manifestations. The clinical status of Leishmaniasis in dogs shows a great variability of symptoms and lesions depending on the level of infestation, the immune status of the host and the stage of disease development and infected organs.

When the disease develops, the symptoms are not immediate: they may appear after a few weeks or even a few months after the bite of sandfly, and these may occur individually or all together, at the same time.