 Parasite
 Host
 Definitive
host
 Intermediate host
 Infective stage
 Diagnostic stage
 Vector
 Life cycle

Protozoa: single-celled organisms
“Multiply in human host”

Helminthes: multicellular worms “Do not
normally multiply in human host”
Amoeba:
Entamoeba histolytica
Acanthamoeba Species
Naegleria Species
Flagellates:
Giardia lamlia
Trichomonas vaginalis
Trypanosoma species
Leishmania species
Ciliates:
Balantidium coli
Coccidia:
Blood and tissue coccidia:
Plasmodium species
Toxoplasma gondii
Intestinal coccidia:
Isospora belli
Cryptosporidium parvum
Trematodes (Flukes):
Schistosoma species
Paragonimus species
Fasiolopsis buski
Cestodes (Tapeworms):
Taenia species
Echinococcus granulosus
Diphyllobothrium latum
Hymenolepis nana (less important)
Nematodes (Roundworms):
Intestinal nematodes:
Ascaris lumbricoides
Enterobius vermicularis
Tricuris trichiura
Strongyloides stercoralis
Ancylostoma duodenale
Filarial and other tissue nematodes:
Wuchereria bancrofti
General lab. Safety:
1- Wear lab coats, gloves,
2- Don’t eat or drink
3- Carefully handle the samples, because it’s
contagious
4- Containers must be labeled probably and
after used closed very well
5- How to dispose wastes
6- Cleaning
7- Safety equipments
Gloves
Lab coat
Mainly we deal with stool as a general
specimen
We can receive also :
1- urine, in case of S.haematobium,
S.mansoni , T.vaginalis.
2- Blood, in case of Plasmodium spp,
trypanosoma, W.bancrofti.
3- Vaginal discharge, in case of T.vaginalis.
4- Sputum, in case of Paragonimus spp.
5-
CSF, in case of Trypanosoma spp,
Naegleria.
6- Bone Marrow, in case of L.donovani.
7- Lymph Gland Aspirate, in case of
Trypanosoma spp, L. donovani.
8- Liver Aspirate, in case of E.histolytica, L.
donovani.
9- Biopsies: - Skin, in case of Leishmania spp,
D. medinensis.
- Muscles, in case of Trichinella.
10- Duodenal Aspirate, in case of G. lamblia,
S. stercoralis.
11- Rectal Scraping, in case of E.histolytica,
Schistosoma spp.

Precautions

Containers

Request form

Time of examination

Macroscopic examination

Microscopic examination

Color : normally brown not pale or dark.

Consistency:
whether
formed,
semi
formed,
unformed, watery.

Composition: Presence of mucus, blood and or Pus

Odor

Whether the specimen contains worms, part of the
worm(segments), larva.
Wet mount :
Either saline or iodine: usually we see the
Cyst stage, we loose the trophozoite
because it’s a fragile stage.

We use 2 clean glass slides: in the first 1
drop of saline and in the other drop of
iodine then by wooden stick take a small
part of sample mix, cover then examine
after removing your gloves .
Saline smear
Iodine smear
saline
Iodine 1%
Huge number of eggs
Huge number of eggs
Trophozoites : by their
motility
Cysts : as the iodine stains
the details.
Disadvantages: The
trophozoites are rapidly
killed by iodine and
therefore become
unidentifiable

Serological
tests:
haemoagglutination
ELISA,
test:
Passive
these
tests
deals with serum Ag and Ab’s.

Molecular tests: PCR, most commonly
used in researches.