Leishmaniasis is a parasitic disease which is caused by leishmania parasite. Leishmania can affect dogs and humans alike. Leishmaniasis is caused by a protozoan parasite from the genus Leishmania and can only be transmitted by certain species of biting sand fly. The disease exists in two forms: cutaneous Leishmania and visceral Leishmania. Both types can affect dogs. Visceral Leishmania is much more serious than Cutaneous Leishmania, since it means that parasites have reached vital internal organs of the dog (black fever).
The infection occurs when flagellated parsites are injected in the host body through sandfly bite. Incubation period from infection to symptoms can range between one month to several years. On most occasion, the infection spreads throughout the body affecting different internal organs and the affected dog develops visceral or systemic disease. Up to 90% of dogs suffering from symptomatic Leishmaniasis have both visceral and cutaneous lesions. Kidneys, skin, spleen, liver, eyes and joints are the main organ systems that are affected by this condition.
It is important to note that leishmaniasis is a zoonotic disease which can be transmitted to humans from dogs.
Since there are two types of leishmaniasis, cutaneous and viscerel, each type has different symptoms.
Visceral — affects organs of the abdominal cavity
Severe weight loss
Loss of appetite (anorexia)
Tarry feces (less common)
Cutaneous — affects the skin
Hyperkeratosis — most prominent finding; excessive epidermal scaling with thickening, depigmentation (loss of skin color), and chapping of the muzzle and footpads
Alopecia — dry, brittle hair coat with symmetrical hair loss
Nodules usually develop on the skin surface
Intradermal nodules and ulcers may be seen
Abnormally long or brittle nails are a specific finding in some patients
Other signs and symptoms associated with leishmaniasis include:
Lymphadenopathy — disease of the lymph nodes with skin lesions in 90 percent of cases
Signs of renal failure — excessive urination, excessive thirst, vomiting possible
Neuralgia — painful disorder of the nerves
Pain in the joints
Inflammation of the muscles
Osteolytic lesions — a "punched-out" area with severe bone loss
Inflammation of the covering of bones; rare
Fever with an enlarged spleed (in about one-third of patients)