Virulence and pathogenicity of parasites Flashcards
3 groups of eukaryotic organisms that aflict health and wellbeing of animals?
- Protozoa
- Helminths
- Arthropods
single celled, nucleated org that causes harm to health?
Protozoa
worm like animals showing differentiation, metazoans
Helminths
3 sub classifications of helminths and short description
Nematode-round worm
Cestode- tapeworm (flat words)
Trematode- fluke (flatworm)
Arachnids and insects, ectoparasites that afflict health and well being of animals?
Arthropods (Entomology)
Lives on the host, causes infestations?
Ectoparasite
Lives in the host, causes infection?
Endoparasite
harbors adult or sexual stage of the parasite?
Definitive host
harbors larval or asexual stage of the parasite?
Intermediate host
an unusual host, unnecessary for the maintenance of parasite in nature?
Incidental host
conferred by a host’s specific immune response developed as a result of a previous parasitic infection?
Acquired immunity
resistance to reinfection or superinfection conferred by presence of parasites that are alive but are in check by host immunity-malaria, toxoplasmosis
Premunition
Parasites have specificity for?
particular definitive and intermediate hosts
Often parasite life cycles can only be completed in?
a particular host
How can disease manifestations differ?
Depends upon whether an animal serves as a definitive, intermediate, or incidental host.
infection dose and the number of organisms acquired over time?
Severity
Ingestion cause of parasite infection?
Giardia, Balantidium coli, Toxoplasma gondii, Cryptosporidium, Cestodes, some Nematodes, some Trematodes
Skin or mucosal penetration cause of parasite infection?
Hookworm, Strongyloides stercoralis; schistosomes
Transplacental (prenatal) cause of parasite infection?
Toxoplasma gondii, Toxocara canis, Strongyloides stercoralis
Transmammary (milk) cause of parasite infection?
Toxocara canis, T. cati, Ancylosotma caninum
Arthropod bite (vector) cause of parasite infection?
Babesia, heartworm, Leishmania, Trypanosomes
Sexual contact: cause of parasite infection?
Tritrichomonas foetus
How does the parasites reproduce in protozoa?
Multiply in Hosts
How do helminths reproduce?
Adult worms do not multiply in the definitive host. Worms die over time, unless the host is re-exposed
The severity of the disease is proportional to worm load introduced into the host.
Attachment of parasites causes?
Cell and tissue damage
Different mechanical or biting mouthparts?
Oral cavity
Attachment organs
Suction disc
direct penetration
Ancylostoma tubaeforme have what kind of attachment?
3 pairs of teeth in buccal cavity
Adult hookworms in the small intestine of infected dogs or cats are attached to the intestinal villi by?
Large mouth cavity (buccal cavity)
-Adult hook worms can cause loss of .2 mL of blood per day
Taenia spp. scolex (T. solium and T. saginata) attach to this area in humans?
small intestine
Attach to villi of small intestine
Giardia intestinalis
TICKS CAN CAUSE? (worst case scenario)
Paralysis
What do Ascaris,
tapeworms, schistosomes, filarial worm cause mechanically?
Blockage of internal organs
What do Echinococcus, Cysticerci cause mechanically?
Pressure atrophy
What do Helminthic larvae cause mechanically?
Migration through tissues
Nematodes will cause ______ to horse’s small intestine?
Rupture (blockage first)
Inflammation causes pathology during worm migration?
Toxocariasis
Anasakiasis,
schistosome cercariae, hookworms use?
Destructive enzymes (toxic parasite product)
African trypanosomes, malaria use?
Endotoxins (toxic parasite product)
Tick paralysis comes from _____ ______ by the tick?
toxic secretions (toxic parasite product)
Parasitic infections can lead to loss of?
Nutrients by the host because they are in competition with host for nutrients like with the fish tapeworm
Giardia duodenalis and Stronglyodies stercoralis interfere with?
Nutrient absorption
Hookworms cause?
iron loss and nutrient loss
In definitive host, adult worms do or do not multiply?
Do not (the reproduce eggs but do not multiply themselves)
