Dogs with Leishmania have been found throughout the Italian peninsula, but the reservoirs of interest were detected in the coastal areas and islands (Argentario peninsula and the island of Elba, about 40% of dogs are sieropositive). Sporadic cases have been observed in dogs that do not live in endemic areas but who have stayed there for longer or shorter periods, however in recent years there has been an increase in these areas, also affecting rural areas with an altitude of 700 / 800 meters from the sea level. This is perhaps due to the increased mobility of the owners or to a change in climatic conditions favouring the colonization of sandflies in new areas. This bug is present in the warm months from April to September.
This disease is considered a zoonotic disease, that is a communicable disease from animals to humans, fortunately not directly but only through the carrier, which by sucking the blood of an infected animal swallows the Leishmania larvae that inside the sandfly's gut perform the evolutionary cycle that makes them ready to infect other individuals including humans. The incubation of the disease does not have a precise and constant length of time and, in fact varies from one month to a few years. The symptomatology is also variable and not very specific (weight loss, asthenia), which leads to a delayed diagnosis. While for humans Leishmaniasis can be classified in three different forms: Cutaneous, Visceral and Muco-cutaneous according to the organs involved. In dogs there is only one generalized form that begins with skin lesions and progresses to the gut. The external signs that can indicate a contagion of leishmania are: thinning hair with dandruff that is not eliminated with a bath, a onychogryphosis (excessive length of the nails), injury to the skin and over time problems affecting the internal organs such as liver, spleen and kidney (nephritis, caused by an autoimmune reaction triggered by the Leishmania and by particular antibodies which results in the production of immune complexes localized in the kidneys and that cause the impairment of therapies and death of the dogs).
The therapies unfortunately are not 100% effective in fact a complete parasitological recovery is almost never achieved. Antimonial compounds were used for the longest time in the treatment of Leishmaniasis. The first antimonial trivalent salt used in the treatment of this pathology was Antimony Potassium Tartrate known as emetic tartar. Its toxicity and therefore the difficulty of dosing it cause its replacement by pentavalent antimony derivatives such as Sodium Stibogluconate and Meglumine Antimoniate. However, the pentavalent Antimony derivatives have a short half-life, so the therapy is long, minimum one month of daily injections. Often a synergy of action is achieved by associating Allopurinol, a hypoxanthine analogue, with a parasitostatic action, which acts by inhibiting protein synthesis in the parasite by blocking the synthesis of RNA. Another molecule used in the therapy of leishmaniasis is Aminosidine sulfate, an antibiotic and antiprotozoal of an oligosaccharide nature which can be used intramuscularly, only in the animals that do not have an impairment of the kidneys. Therefore the use of this product is limited by its nephrotoxicity and ototoxicity. A good anti-leishmania parasiticide, is amphotericin-B an antibiotic produced by Streptomyces nodosus, which irreversibly kills the parasites by binding to ergosterol in the cell membrane, but also presents a certain nephrotoxicity for which it must be used under strict medical supervision. In humans a special formula is successfully used, that is Amphotericin B lysosomal which, however, is not used on animals, as it is expensive and not sufficiently tested on them. Unfortunately Leishmaniasis is a problem that every year becomes more present and incisive. Perhaps for more than any other disease prevention is the most effective weapon. The products to use are all anti-flea and anti-tick in particular those based on Neem oil that also have higher repellent activity. In addition to the use of these products one should also follow rules of conduct such as preventing the dog from staying in the open during the evening and at night in the places declared at risk.
In these few lines I have tried to explain the difficulties related to the treatment of this disease, which can be defeated only after an early diagnosis by Veterinarians. To do this it is necessary to often subject the animal to controls, especially after a stay in the places now defined within the range of the Leishmania.