1 Leishmaniasis Leishmania donovani (complex) (VL) Leishmania tropica (CL) Leishmania major (CL) Leishmania aethiopica (CL) Leishmania mexicana (Complex) (CL) Leishmania brazilliensis (complex) (MCL) Leishmania peruriana

2 The Parasite PhylumPhylum OrderOrder FamilyFamily GenusGenusSarcomastigophoraKinetoplastidaTrypanosomatidaeLeishmania

3 Morphology PromasitogtePromasitogte InsectInsect MotileMotile MidgutMidgut Amastigote Amastigote Mammalian stageMammalian stage Non-motileNon-motile IntracellularIntracellular Digenetic Life Cycle

4 Morphology Promastigote Amastigote Flagella Kinetoplast Golgi Nucleus Cytoskeleton

5 Promastigote

6 Amastigotes (*) of Leishmania donovani in the cells of a spleen. The individual amastigotes measure approximately 1 µm in diameter.

7 Amastigote

8 Amastigotes of Leishmania in a macrophage from a lymph node of a dog.

9 Leishmania (Leishman- Donovan or LD bodies). Lying in macrophage cells from liver. Giemsa. × Enlarged by 9.6.

10 A macrophage filled with Leishmania amastigotes.

11 Life cycle The organism is transmitted by the bite of several species of blood-feeding sand flies (Phlebotomus) which carries the promastigote in the anterior gut and pharynx. It gains access to mononuclear phagocytes where it transform into amastogotes and divides until the infected cell ruptures. The released organisms infect other cells. The sandfly acquires the organisms during the blood meal, the amastigotes transform into flagellate promastigotes and multiply in the gut until the anterior gut and pharynx are packed. Dogs and rodents are common reservoirs. The organism is transmitted by the bite of several species of blood-feeding sand flies (Phlebotomus) which carries the promastigote in the anterior gut and pharynx. It gains access to mononuclear phagocytes where it transform into amastogotes and divides until the infected cell ruptures. The released organisms infect other cells. The sandfly acquires the organisms during the blood meal, the amastigotes transform into flagellate promastigotes and multiply in the gut until the anterior gut and pharynx are packed. Dogs and rodents are common reservoirs.

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13 Mammalian Hosts RodentsRodents GerbilsGerbils HyraxesHyraxes BatsBats PorcupinesPorcupines OpossumsOpossums Sloths Sloths Primates Primates Dogs Dogs Foxes Foxes Anteaters Anteaters

14 Vectors Phlebotomine Sandflies 6 genera world wide distribution Phlebotomus & Lutzomia 500 species Females Haematophagus Males sap feeders

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16 Clinical Disease Visceral Fatal (90% untreated) Liver Spleen Bone marrow Cutaneous Generally Self- healing Skin Mucous membranes SPECTRUM OF DISEASE

17 Initial Infection Similar in all species Inoculation of promastigotes Inflammation & chemotaxis Receptor mediated phagocytosis Promastigote Amasitgote Transformation

18 Parasite Spread Macrophage lysis & parasite release Lymphatic spread Blood spread Target organs Skin/lymph nodes/spleen/liver/ bone marrow

19 Visceral Leishmaniasis William Leishman Pentavalent antimony Experimental transmission Leishmania donovani (Complex) L.d. archibaldi - L.d.chagasi - L.d.donovani - Ld.infantum

20 VL - Clinical Manifestation Variable - Incubation weeks Lowgrade fever Hepato-splenomegaly Bone marrow hyperplasia Anemia, Leucopenia & Cachexia Hypergammaglobulinnemia Epistaxis, Proteinuria, Hematuria

21 Profile view of a teenage boy suffering from visceral leishmaniasis. The boy exhibits splenomegaly, distended abdomen and severe muscle wasting.

22 A 12-year-old boy suffering from visceral leishmaniasis. The boy exhibits splenomegaly and severe muscle wasting.

23 Jaundiced hands of a visceral leishmaniasis patient.

24 Enlarged spleen and liver in an autopsy of an infant dying of visceral leishmaniasis.

25 Post Kala Azar Dermal Leishmanoid Normally develops <2 years after recovery Recrudescence Restricted to skin Rare but varies geographically

26 Cutaneous leishmaniasis of the face.

27 A cutaneous leishmaniasis lesion on the arm.

28 INFECTION Sub-clinical or inapparent infection Recovery Death Immune to reinfection Concurrent infection PKDL

29 Diagnosis Clinical signs & symptoms Hypergammaglobulinemia ELISA/Formol gel Bone marrow biopsy Spleen or liver biopsy Culture & Histology

30 Speciation Similar morphologySimilar morphology Isoenzyme profiles - ZymodemesIsoenzyme profiles - Zymodemes Monoclonal antibodiesMonoclonal antibodies DNA hybridisation - PCRDNA hybridisation - PCR

31 Treatment Good nursing DietAntibiotics Pentavalent antimony Pentamidine New drugs - New delivery

32 Control Vector controlVector control Reservoir controlReservoir control Treatment of active casesTreatment of active cases VaccinationVaccination