The document discusses Trypanosoma parasites, including their morphology, life cycles, diseases caused, and methods of transmission. Trypanosoma can be transmitted by tsetse flies or kissing bugs and cause African sleeping sickness or Chagas disease, respectively. They have different morphological forms depending on their host and life cycle stage. Treatment involves drugs targeting the acute or chronic phases of the diseases. Control relies on treating infected hosts and controlling the insect vectors.

1. College of Health Sciences
Dep. of Medical Laboratories
Parasitology Theory
3rd stage
Lecture 5
Dr.: Shameeran S. Ismael
BVM & S, M.Sc Medical Microbiology(Parasitology),
PhD Molecular Parasitology

2. II Class: Flagellates
3. Haemo-Flagellate parasite
Trypanosoma spp.
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

3. 3.Trypanosoma Spp.
• Parasitic protozoa of blood
and/or tissues of mammals.
• Trypanosoma are present in
blood , lymph , lymphoides
and cerebrospinal fluid.
Trypanosoma is multiply by
longitudinal binary fission
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

4. Trypanoaoma spp.
Kingdome: Protista
Phylum: Protozoa
Sub-phylum: Sarcomastigophora
Class: Mastigophora
Order: Kinetoplastida
Family: Trypanosomatidae
Genus: Trypanosoma
Species: T. brucei gambiense
T. brucei rhodesiens
T. cruzi Shameeran S. Ismael veterinary
protozology theory, 202011/28/2020

5. Disease: Trypanosomiasis as general
African Trypanosomiasis (T.brucei) and American
Trypanosomiasis (T. Cruzi)
Final host: Man
Site of infection: blood
Infective stage: metacyclic Trypomastigote
Life cycle: Indirect direct
Vector: for Glossina (tsetse fly)is vector for Trypanosoma
brucei and Triatoma (kissing bug) is vector for
Trypanosoma cruzi
Shameeran S. Ismael protozology
theory.Dep.Medical Laboratories, 2020

6. Infection:
1. In African Trypanosomiasis, infection occur when
TseTse fly inject Metacyclic Trypamastigote in to
blood during biting and blood meals
2. In American Trypanosomiasis, infection occur
when feces of Bug containing Metacyclic
Trypamastigote contaminated the wound
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

7. There are another mode of infection:
• Mother to child transmission
• Mechanical transmission
• Accidental infection from laboratories
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

8. Morphology :-
• Trypanosmes is an elongated , spindle-shape with a
single nucleus near the middle of parasite.
• It has kinetoplast
• It has undulating membrane
• Possess a slender-single flagella at the anterior end
• Flagellum serve as organ of attachment and locomotion
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

9. Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

10. There are four morphological stages :-
1.Trypamastigote:
A blade like form with a kinetoplast posterior to the
nucleus, undulating membrane is well developed and
free flagellum is often resent. Its found in vertebrate
and arthropods.
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

11. 2. Epimastigote: Kinetoplast lie anterior to the nucleus
and the undulating membrane is short, this stage
found in the vertebrates but it’s a stage in arthropods.
3.Promastigote: kinetoplast and axoneme are at the
anterior tip of the body, there is no undulating
membrane. Its found in arthropods.
4. Amastigote: The body is rounded, a flagellum is
absent or is represented a short fibril, kinetoplast is
present, body is found in vertebrate and arthropods
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

12. Trypomastigote Epimastigote Promastigote Amastigote
FORM
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

13. Trypanosoma
Shameeran S. Ismael veterinary
Trypanosomiasis
American
Trypanosomiasis
East African
Trypanosomiasis
Transmitted byTransmitted by
Causes
T.brucei
rhodesiense
T.brucei gambiense T.cruzi
Sleeping sickness
Chagas’ disease
West African
Trypanosomiasis
Glossina (tsetse fly) Triatoma (kissing bug)
11/28/2020

14. Trypanosoma divided into two station:
1. Salivarian station (Anterior station)
2. Stercorian station (Posterior station)
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020
1.Anterior Station:
The epimastigote multiply in the gut of arthropodes and
infective stages metacyclic trypomastigote forms accumulate
in the mouth parts or salivary glands, so that the infection is
transmitted when the arthropods take a blood meal.

15. Mechanism of disease transmission by Tsetse fly
Bite of ♂ & ♀
Trypomastigotes
(polymorphic trypanosomes)
Diagnostic
stage
12-42µ
Epimastigote
Full of short
stumpy metacyclic
Trypomastigote
3 weeks
Infective stage
Biological transmission
Salivary
gland
Tsetse fly
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

16. Saliverian station including:
1.T. b. gambiense:
• It’s the cause of gambeinse sleeping sickness for man
in Africa, disease is transmit by TseTse fly
• Disease is chronic occur by invasion of blood and
lymph node by the parasite, CNS infected finally
leading to coma and death.
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020
2. T. b.rhodesinse
•Causing East African sleeping sickness for human

17. Life cycle of anterior Trypanosomiasis
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

18. Pathogenesis and clinical signs:
There are two stages:
a) Haemolymphatic stage: parasites are multiplies in
peripheral circulation, subcutaneous tissues and
lymph and lead to:
1.Lymphoid enlargement and spleenomegaly associated
with plasma cell hyperplasia,
hypergammaglobulinaemia, ultimately in infection
of long duration, the lymphoid organ become
shrunken due to exhaustion of their cellular
elements.
2.Anemia: haemolytic anemia and leading to sub/cut
Odema and emaciation.
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

19. b) Neurological/Meningoencephalic stage: enters CNS by
crossing blood brain barrier and cause cell
degenaration and inflammatory infiltrates occur in
muscles, CNS and myocardium
Note: Both stages without treatment the disease is fatal
Diagnosis of African Trypanosomiasis:
by microscopic examination of blood smear for motile
trypanosomes with Giemsa stain.
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

20. Treatment:
I. Treatment of stage one of disease:
1.Pentamidine:
Used against T.b.gambiense - generally well
tolerated
2.Suramin:
Used against T.b.rhodesiense - causes Urinary
tract problems and allergic reactions
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

21. 2. Treatment of stage of disease
1.Melarsoprolol:
Is used against both the species - causes reactive
encephalopathy which can be fatal
2.Eflornithine: -
Is effective against T.b.gambiense only treatment
regimen is strict but less toxic than
melarsoprolo
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

22. 2. Posterior station ( Sterocoraria)
• The metacyclic trypomastigotes accumulate in the
hind-gut and are passed in the faces of arthropods.
Infection of vertebrate occur by contamination of the
skin wounds.
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

23. Mechanism of disease transmission by winged bug
Shameeran S. Ismael veterinary
T.cruzi in human blood
Epimastigote
form
Short stumpy
metacyclic
trypomastigote
(infective stage)
Pass out with faeces
Cyclopropagative
transmission
Alimentary
canal of
bug
11/28/2020

24. Posterior station ( Sterocoraria) including:
Chagas disease, or American trypanosomiasis, a zoonotic
disease that is caused by the parasite Trypanosoma cruzi.
Infection is most commonly acquired through contact with
the feces of an infected bug (or "kissing bug"), a blood-
sucking insect that feeds on humans.
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

25. Life cycle of Posterior Trypanosomiasis
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Shameeran S. Ismael veterinary
protozology theory, 2020

26. Pathogenesis
• Disease may be acute or chronic characterized
by myocarditis, megaoesophagus and
megacolon.
• Result of dis. Is massive destruction of the
reticuloendothelial tissue and muscles of
viscera and causing death.
Shameeran S. Ismael veterinary
protozology theory, 2020
11/28/2020

27. Clinical signs:
Chagas disease has two phases an acute and
chronic phase:
1.Acute phase: It occurs immediately after the
parasite entry into the body and may last for 2
months
• Infection may be mild or asymptomatic
Parasites are usually found in the blood during
this phase and the main symptoms includes
fever, headache, enlarged lymph glands, pallor,
muscle pain , difficulty in breathing, etc
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

28. 2. Chronic phase
• After the acute phase most patients go into the
“chronic indeterminate” phase, where parasites
are not found on blood Patients are unaware
and may remain asymptomatic for life
• About 30% may develop cardiac
complications and upto 10% may develop G.I.
complications and neurological problems In
later years, patient may die from progressive
cardiac failure due to destruction of heart wall
by the parasite.11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

29. Romana’s sign:
• Romana sign, also known as chagoma, refers
to periorbital swelling, palpebral edema and
conjunctivitis seen 1-2 weeks following
infection with Trypanosoma cruzi.
• When bug bit the man and contaminated the
wound, the feces is rubbed by the host, the
parasite may enter into the host through breaks
in the skin or through eye or through mucous
membrane and characterized by Swelling of
the eyelid on one eye is known as Romana’s
sign.11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

30. Diagnosis:
1.Acute phase: Blood smears are used for
diagnosis of acute phase (Both thick and thin
smears) can be made and stained with Giemsa
stain for microscopic visualization of the
parasite
2.Chronic phase: Clinical findings along with
clinical history is used for diagnosis of chronic
phase. Two or more serological tests are also
necessary to support the diagnosis
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

31. Treatment:
1. Acute phase: Benznidazole and nifurtimox
are 100% effective against the parasite during
the acute phase
2. Chronic phase: Cardiac drugs may be given
as per the symptoms of the patient
Benznidazole and nifurtimox are effective in
immunosuppressed patients and in children
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

32. Control
1. Control of African Trypanosomiasis:
• Treatment of infected host
• Control of TseTse fly
• Use of Pentamidin as prophylactic drug
2. Control of American Trypanosomiasis:
• Treatment of infected host
• Control of Bug
• Elimination of reservoir hosts
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020

33. Thanks for attention,,,,
11/28/2020
Shameeran S. Ismael veterinary
protozology theory, 2020