1. Leishmaniasis David P. Humber Department of Life Sciences University of East London

2. Lecture Topics The parasite and vector The life-cycle Clinical features Diagnosis Epidemiology Chemotherapy Vaccination

3. Introduction Leishmaniasis Protozoal disease of mammals Largely zoonotic 23+ pathogenic species Cutaneous leishmaniasis Visceral Leishmaniasis

4. The Parasite Phylum Order Family Genus Sarcomastigophora Kinetoplastida Trypanosomatidae Leishmania

5. Morphology Promasitogte –Insect –Motile –Midgut Amastigote –Mammalian stage –Non-motile –Intracellular Digenetic Life Cycle

6. Morphology PromastigoteAmastigote Flagella Kinetoplast Golgi Nucleus Cytoskeleton

7. Scanning EM of Promastigote Rosette

8. Promastigote in Culture Kinetoplast Nucleus

9. Scanning EM TIA

10. Amastigotes - skin biopsy

11. Speciation Similar morphology DNA bouyant density Isoenzyme profiles - Zymodemes Monoclonal antibodies DNA hybridisation - PCR

12. Species Pathogenic in Humans Leishmania aethiopica Leishmania brazilliensis (complex) Leishmania donovani (complex) Leishmania major Leishmania mexicana (complex) Leishmania tropica

13. Mammalian Hosts Rodents Gerbils Hyraxes Bats Porcupines Opossums Sloths Primates Dogs Foxes Anteaters.....

14. Canine Host

15. Procavia capensis

16. Sloth Host

17. Distribution of Leishmaniasis

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

20. Sandfly - Phlebotomous pedifer

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

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

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

24. Visceral Leishmaniasis 1903 1920 1931 William Leishman Pentavalent antimony Experimental transmission Leishmania donovani (complex) L.d. archibaldi - L.d.chagasi L.d.donovani - Ld.infantum

25. VL - Clinical Symptoms Variable - Incubation 3-100+ weeks Lowgrade fever Hepato-splenomegaly Bone marrow hyperplasia Leucopenia & Cachexia Hypergammaglobulinnemia

26. Visceral Leishmaniasis

27. Epidemiology - Distribution

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

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

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

31. Biopsy punch

32. Specificity of L. aethiopica primers Marker L.. aethiopica L. tropica L. major L.. donovani

33. Treatment Good nursing & Diet Antibiotics Pentavalent antimony (upto 25% ressistance) Pentamidine Amidosidine New drugs - New delivery

34. Immune Response Innate IRs –Lsh/BCG gene Lsh r Lsh s –No real human equivalent –Other species specific genes described –Complement –Polymorphs –Macrphages

35. Macrophages Receptors –CR3 receptors for C3bi –Lipophosphoglycan –GP63 Killing Oxygen dependent Oxygen independent

36. Macrophage activation T cell activation –TH - 1 IL2, Gamma interferon –TH - 2 IL4, IL5 SALT –Langerhans cells –Tissue dendritic cells

37. Vaccines Leishmania + BCG –Ecuador - 3 species (Lbb,Lbg,Lma) 2 doses killed whole parasites 70% protection –Iran - 1 species (Lt) 1 dose whole killed 35% responded 0% cf BCG alone

38. CL - Cutaneous Leishmaniasis Old World –Leishmania aethiopica –Leishmania major –Leishmania tropica New World –Leishmania brazillensis L.b. –Leishmania mexicana L.m Spectrum LCL - MCL - DCL

39. Localised Cutaneous Leishmaniasis Single or multiple lesions –Usually on head and/or neck Generally self-healing –Variable few week to many months Ulceration followed by healing & scar –Secondary infection & tissue erosion

40. Localised Cutaneous Leishmaniasis

41. Mucocutaneous Leishmaniasis Direct inoculation or extension –L.aethiopica & others –Low cell mediated immunity (CMI) Metastatic spread –L.b.brazilliensis –High CMI & extensive tissue destruction –Also in DCL but no MI no tissue damage

42. Mucocutaneous Leishmaniasis

43. Diffuse Cutaneous Leishmaniasis Multiple diffuse spreading lesions –Usually face & limbs rarely trunk No ulceration Non-healing - life long infection No cell mediated immunity Good antibody response Leishmania aethiopica & Leishmania mexicana mexicana

44. Diffuse Cutaneous Leishmaniasis

45. Uta

46. Epidemiology Old World

47. Epidemiology New World

48. Diagnosis Clinical feature & geographical location Skin biopsy/slit skin smear Culture & histology Monoclonal antibodies PCR

49. Treatment Control secondary infection Self-healing - probably no treatment Surgery/cryosurgery/Topical MCL & DCL Pentavalent antimony - pentamidine

50. Control Vector control Reservoir control Treatment of active cases Vaccination