Parasite can effect human easily so pay attention

Seminar

1. Lab 3

By: Mrs. Zhima M. Rasheed


Parasitology
Protozoa
Flagellates

2. The Flagellate
Parasitic protozoa which possess whip-like flagella
as their organs of locomotion.

There are classified as follow:-

Phylum: Sarcomastigophora
Subphylum: Mastigophora
Class: Zoomastigophorea

3. Intestinal and Atrial flagellates:

 Most of them are nonpathogenic commensals, Two of
them cause clinical disease.
Parasite site of infection
1. Giardia lamblia (duodenum, jejunum)
2. Trichomonas vaginalis (vagina, urethra)
3. Trichomonas tenax (mouth)
4. Trichomonas homonis (caecum)
5. Chilomastix mesnili (caecum )
6. Enteromonas homonis ( colon)
7. Retortamonas intestinalis ( colon)
8. Dientamoeba fragilis (colon )

4. Intestinal Flagellates'
Giardia lamblia (Giardiasis)
Pathogenic flagellate
Inhabit the small intestine ( duodenum and jejunum) of man
Half pear-shaped with cup like ventral surface.
Cysts are small, compact.
Reservoirs include cattle, coyotes, cats, and humans.
Cysts can survive for 2 months in environment.

5. Trophozoit stage

Trophozoit of Giardia is a 12 to 15 micrometer
It has (tennis racket) or (tear drop) shape.
It has two axostyles(vertebrate column) ,
two nucleus (each with large karyosome) and (4) pairs of flagella .
the ventral surface has sucking discs for sucking during feeding
It is actively motile by flagella & multiply by binnary fission .
The trophozoite attaches to the lining of the small intestine with a
"sucker" and is responsible for causing the signs and symptoms of
giardiasis.

8. Cyst stage

1)Giardia cysts are 9 to 12 micrometer
2)The cyst is oval shape
2) It has two axostyle
3) Two pairs of nuclei
4) Two pairs of median bodies
MB: defined as the inferior portions of the flagella.

9. Life cycle (Giardiasis)
Infection: Ingestion of cysts, usually in contaminated water or by the
fecal-oral route.
Infective stage: Cysts (survive several months).
Diagnostic stage: Cysts and trophozoites , can be found in the feces.
•Man, pigs and monkeys are infected.
Symptoms (Giardiasis)
Early symptoms include flatulence, abdominal distension, nausea
and foul-smelling bulky, Diarrhea.
The chronic stage is associated with vitamin B12 malabsorption.

10. Mode of transmission
Mainly through contaminated food and water.
By direct person to person spread (poor sanitation).
Laboratory Diagnosis:
1. Specimen: Stool, jejunal biopsy
2. Microscopy: In the wet mount preparation trophozoites ( liquid stool)
and cyst forms (formed stool) are seen.
•Staining by giemsa.
•The standard diagnostic method is stool examination to detect cysts and
(more rarely) trophozoites.
3. Serology: Antibody (ELISA), Antigen in the stool (CIEP and ELISA).

11. Trichomonas vaginalis
Parasitic protozoa which possess whip-like flagella as
their organs of locomotion.
3 infect humans:
1.T. vaginalis
2.T. tenax
3.T. hominis

12. Trichomonas vaginalis
1)Infection of male and female uro-genital tracts.
2)Sexually transmitted.
3)Only in trophozoite form

Morphology(Trichomonas vaginalis )

1)Trophozoite form 15 to 18 micrometers
2) Half pear shaped with a single nucleus.
3) Four anterior flagella and a lateral flagella.
4)attached by an undulating membrane.

14. Life cycle (Trichomonas vaginalis )

Infection occurs by sexual contact.
Trichomonas vaginalis colonizes the vagina of women and the
urethra (sometimes prostate) of men.

15. Symptoms (Trichomonas vaginalis)
1) In men, may cause mild urethritis or prostatitis.
2) In women, in heavy infections may cause vaginitis
sometimes with foul-smelling yellowish.
Diagnosis (Trichomonas vaginalis )
1) Finding the organism in vaginal discharge
(by Giemsa-stained smears).
2) Cultivation of a swab sample.

16. Microscopy for T. vaginalis diagnosis
Procedure:
1.A sample of vaginal discharge or collect specimens with
a Dacron swab or speculum.
2.Then mix a sample with a small drop of saline (0.85%
Nacl) on a glass slide and put a cover slip.
3.Check it under the microscope.
4.The flagella movement will be clear under microscope.

18. Trichomonas Tenax
•Its pyriform flagellate. It measures 5-12 um in length
and 5-10 um in width.
•It’s a harmless commensal of the human mouth,
living in the tartar around the teeth.
•Its transmitted by kissing, salivary droplet.
•Diagnosis can be made by demonstration of T. tenax in
the tartar by microscopy, and no therapy indicated.

19. Trichomonas Hominis
•It’s a pyriform, measuring 5- 14 um in length and 7-10 um in
width.
•It inhibits the caecum of man and feeds on enteric bacteria.
•It doesn’t invade intestinal mucosa
•T. hominis does not typically cause significant disease in
humans.