General Parasitology - LEC 2 Flashcards
multicellular, bilaterally symmetrical, elongated, flat or round organisms
Helminths
2 phyla of helminths that parasitize humans
Phylum Platyhelminthes
Phylum Nematoda
Helminths are ______ in size and often visible to naked eyes
macroscopic
Nematodes’ larvae (3)
Rhabditiform
Filariform
Microfilaria
Cestode’s larvae (7)
Cysticercus
Cysticercoid
Coenurus
Coracidium
Procercoid
Plerocercoid
Hydatid cyst
Trematode’s larvae (5)
Miracidium
Sporocyst
Redia
Cercaria
Metacercaria
reside in lymphatic system or in the blood
Microfilaria
Parasite that has microfilaria larva, it is a blood and tissue parasite
Wuchureria bancrofti
They complete their life cycle in one host
Nematodes
Nematodes that require 2 hosts (man and insect vector/cyclops)
filarial nematodes and Dracunculus medinensis
They complete their life cycle in 2 different hosts
Cestodes
Cestodes that doesn’t require 2 hosts to complete their life cycle
Hymenolepis nana
For most cestodes, man is the
definitive host
Identify the cestode parasite that make MAN AS ITS INTERMEDIATE HOST
Echinococcus granulosus
cestode parasite: the man serves as both definitive and intermediate host
Taenia solium
They complete their life cycle in 1 definitive host (man) and 2 intermediate hosts (freshwater snail, fish/crab)
Trematodes
Ascaris lumbricoides infective stage in humans
embryonated egg with L3 larva
where does soil transmitted helminths embryonate?
soil
diagnostic stages of A. lumbricoides
fertilized eggs/ovum and adult worms in small intestine
Class cestoda is divided into two orders
Cyclophyllidea
Pseudophyllidea
class cestoda that needs water to embryonate eggs
Pseudophyllideans
class cestoda that needs soil to embryonate eggs “terrestrial”
Cyclophyllideans
class cestoda that contained in bladder/cyst, fluid-filled (bladder larva)
Cyclophyllideans
class cestoda that is not contained in cysts
Pseudophyllideans
[cyclo] Larva in Taenia multiceps
Coenerus
Larva in Taenia saginata and T. solium
Cysticercus
Larva in Hymenolepis spp.
Cysticercoid
[cyclo] T. solium and saginata eggs/ova when consumed affects the brain of humans. The disease caused by the said spp is called______
Cysticercosis
Pseudophyllideans L1 larva (ciliated with hooks)
Coracidium
Pseudophyllideans L2 larva (with cercomere, 3 pairs of hooklets)
Procercoid
Pseudophyllideans L3 larva (
Plerocercoid/sparganum
Disease cause by the ingestion of Plerocercoid/sparganum or the L3 larva of Pseudophyllideans.
Sparganosis disease
Trematodes’ intermediate host
snails (gastropods)
Earliest larva of trematodes
miracidium larva
Infective stage of 1st intermediate host (snail)
Miracidium
Infective stage of 2nd intermediate host (cow,sheep)
Cercaria
encysted stage of a fluke in its final intermediate host (definitive host)
Metacercaria
Miracidia is developed inside the nail through stages of what
mother sporocyst-daughter sporocyst
redia (I) - redia (2)
hanggang maging cercariae
Trematodes require water to embryonate. T or F
True
If schistosoma spp na trematodes, wala siyang stage na ______
redia larva stage
Basta tandaan ang trematodes may primary and secondary host
sige po
Worms (nematodes) na may plug sa structure
Adenophorea
Nematodes naman na walang plug (round kasi)
Secernentea
Adenophorea’s larval stage infective to definitive (final host)
First larval stage (trichinella)
Embryonated egg (trichuris)
Difference of Adenophorea and Secernentea in terms of EXCRETORY SYSTEM
adeno-without lateral canals
secer-with lateral canals
Difference of Adenophorea and Secernentea in terms of CAUDAL PAPPILAE
Absent or onti lang sa Adeno
tapos sa secer madami (numerous)
Secernentea’s larval stage infective to definitive host
Third larval stage/embryonated egg
Filarial hosts (3)
1 man DF
2 IH (snails, insects)
Dracunculus medinensis intermediate host
cyclops/waterflea/copepod
Sa E. granulosus, yung tao is intermediate host. Infected parin siya ng larva ng parasite. Kaya nga yung larva na cysticercoid nagcacause ng disease na____
Cysticercosis
Taeniasis, man is the definitive host.
TRUE
location where the eggs are laid.
Ovipositioning medium
Schistosoma spp are diecious because
they can reproduce their own eggs.
term for “bump” in adenophorea
Protusion
Disease caused by T. cati and T. canis
VLM (visceral larva migrans)
OLM (ocular larva migrans)
crown like structure on a tapeworm (korona siya sis)
Rostellum
attachment of parasite to intestine
Sucker
If may spine/hooklets ang head ng parasite, tinatawag na ____
Armed scolex
If walang spine/hooklets ang head ng parasite, tinatawag na ____
Unarmed scolex
Toxocara spp have ___ number of sucker
four
Trematodes have ___ no. of sucker
2
what do you call the sucker of trematodes
oral sucker
ventral sucker
Ventral sucker is called
Acetabulum
Nematodes shape
elongated, cylindrical, unsegmented
Cestodes shape
tape-like, segmented
Trematodes shape
Lead-like unsegmented
Nematodes, mas malaki babae kesa lalaki. diecious
omsim
Trematodes monoecious sila, except sa schistosoma spp. na mas malaki lalaki kesa babae (diecious)
opo
HEAD ng nematodes
No sucker
No hooks
Some spp have well-developed buccal capsule
HEAD ng cestodes
may sucker
may hooks (often)
ALIMENTARY CANAL ng nematodes
complete
may anteriorly terminal mouth and posteriorly subterminal anus
ALIMENTARY CANAL ng Cestodes
WALA HAHAHAH
ALIMENTARY CANAL ng Trematodes
Meron pero incomplete tapos wala siyang anus
Difference of nematodes, cestodes, trematodes in terms of BODY CAVITY
Nematodes - present
Cestodes - absent
Trematodes - absent
Nematodes Mode of Infection
✓ ingestion of eggs
✓ penetration of larvae thru surfaces
✓ arthropod vector
✓ ingestion of encysted larvae
Cestodes mode of infection
✓ infection by encysted larvae
Trematodes mode of infection
✓ infection, larval stages
✓ entering intestinal tract
✓ penetration thru skin
How helminths affect man?
✓Pathological lesions
✓ Malnutrition
Clinical manifestations (acute,)chronic
exaggerated immune response of body against the parasite
Hypersensitivity reactions
dxs caused by malnourishment
Helminthiasis
Acute - kusang gumagaling
self-limiting disease
Chronic - fatal if left untreated e.g., Taeniasis (1year), malaria
leishmania (leishmaniasis-altho protozoan na to)
Chronic dxs
Scientific term of head louse
Pediculus humanus capitis
Scientific term of body louse
Pediculus humanus corporis