LEISHMANIASIS 2016-2017

Leishmaniasis is one of the most important vector-borne diseases
of humans. This parasitic disease can be caused by many species of
Leishmania (over 20 Leishmania species), most of which are
zoonotic.
In humans, different species of the parasite are associated with
different forms of the disease.
Many Leishmania spp. cause skin ulcers and nodules. A few of
these organisms can also affect the mucous membranes, and may
cause disfiguring lesions of the nose.
Other species damage the internal organs and cause human visceral leishmaniasis which is a life-threatening condition.
Among domesticated animals dogs are the most important species in the epidemiology of this disease.
Leishmania transmitted to humans by the bite of infected female phlebotomine sandflies. Over 90 sandfly species are known to transmit Leishmania parasites.
It is chronic systemic disease caused by intracellular protozoa of the
genus leishmania. The disease is characterized by fever, Hepato-
splenomegaly, lymphadenopathy, anemia, leukopenia,
thromboocytopenia and progrssive emaciation and weakness.
Untreated clinical disease is usually fatal.
Post kala-azar dermal leishmaniasis consist of macular, papular
and/or nodular skin lesions that occur weeks to years after
apparent cure of systemic disease. Post kala-azar dermal
leishmaniasis occur in about 50% of visceral L. in Sudan and in 10-
20% of cases in India.
Infectious agents:
Typically Leishmania donovani , L. infantum and L.infantum/
chagasi.
Reservoir:
Humans , wild Canidae (foxes and jackals) and domestic dogs.
Incubation period:
generally 2-6 months ranging from 10 days to years.
Period of communicability:
Not usually transmitted from person to person but infectious
to sandflies as long as parasites persist in the blood or skin
of reservoir.
Infectivity for phlebotomines may persist after clinical
recovery of human patients.