PID parasit Flashcards
Dz of a parasite is dependent on?
- Location in host
- # ’s (dose) for infestations
- Host response
○ Immune system
○ Age of host
the mouth of a flea has a? and is used for?
provoskis
sucking blood
what is the most common dermatitis?
FAD
flea allergy dermititis
what are There are 3 main classes of
parasites that can cause
disease in humans
helminths
ectoparasites
protozoa.
Toxocara canis can cause __________ in humans.
Visceral Larval Migrans
or Ocular Larval Migrans
Ancylostoma braziliense can cause __________ in humans.
Cutaneous larval migrans
Taenia solium can cause __________ in humans when they serve as an accidental host.
Cysts in brain (neurocysticercosis)
cause epilepsy, blindness, madness
and death
Diagnostic methods for parasitology
- Host Species
- Site of Infection
- Size of parasite
broad Tx and prevention of parasites
Parasiticides • Sustainable management of the host • Management of the environment • Life cycle is used to determine treatment and prevention
the class of Nematoda refers to
Round worms
the class cestoda refers to
tapeworms (segmented worms)
the class trematoda refers to
Flukes
the phylum Anthropada refers to what classes
Insecta
Arachnida
Subkingdom Protozoa refers to what phylums
Phylum Mastigophora
Phylum Apicomplexa
the Phylum Nemathelminthes refers to the class of?
• Class Nematoda (Roundworms)
Phylum Platyhelminthes refers to the classes of? and they are?
the Flatworms
- Class Cestoda (Tapeworms)
- Class Trematoda (Flukes)
Nematodes characteristics
round worms - Free-living or parasitic • Elongate/cylindrical • Alimentary canal present • Sexes usually separate • Life cycle direct or indirect
Cestode characteristics
segmented worms • Flat body and no alimentary canal • Scolex (holdfast organ) • Strobila (body) with proglottids • Each proglottid- hermaphroditic • Indirect life cycle • Types of characteristic larval stages
Trematodes charicteristics
flukes • Dorso-ventrally flattened • Leaf-like • Oral and ventral suckers • Indirect life cycle- molluscan IH • Usually genitally independent
Arthropods ID characteristics and examples are
Insects • Adults: 3 pairs of legs (6 legs) • Head, thorax, abdomen • Antenna • Flies (Diptera) • Fleas (Siphonaptera) • Lice (Phthiraptera) • Hemiptera
Arachnids – Acari - ID characteristics are
• Nymphs and adults: 4 pairs of legs (8 legs) • Larvae: 3 pairs of legs • Body: cephalo-thorax and abdomen • No antennae, but palps • Ticks • Mites
Protozoa ID characteristics are
how are they classified and what are the examples?
Classified based on their mode of locomotion • Locomotion is accomplished by: Pseudopodia Flagella Gliding movements Cilia
the host that harbors adult (sexual) stage of
the parasite is.
Definitive host —
a host that harbors larval (asexual) stage(s) of the parasite while the parasite matures is
Intermediate host
a Paratenic host is?
a host that harbors parasite but it does not
undergo further development in this host; aka a transfer host
an animal (definitive) host that serves to maintain the parasite’s life cycle in the environment
Reservoir -
an Incidental host is?
- an unusual host, unnecessary for the maintenance of the parasite in nature
Host specificity
Parasites (particularly helminths) have
specificity for particular definitive and
Often parasite life cycles
intermediate hosts.
can only be completed in a particular host,
Disease manifestations may be different
depend upon whether an animal serves as a __________, __________ or an ____________host.
definitive, intermediate, or an incidental
Veterinary Parasitology has
Three groups of eukaryotic organisms that
afflict health and wellbeing of animals. they are?
— Protozoa (Protozoology): Single celled, nucleated
— Helminths (Helminthology): )
— Arthropods (Entomology): arachnids and insects;
ectoparasites
the phylum of helminthes can be further broken down into 3 groups of _______. each different from the other. explain.
Worm-like animals showing differentiation, metazoans Nematode — roundworm Cestode — tapeworm (segmented flatworms) Trematode — fluke (flatworms
Ectoparasite —Lives \_\_\_\_ the host and Causes \_\_\_\_\_\_\_\_\_\_ Endoparasite —Lives \_\_\_\_\_\_\_ the host —Causes \_\_\_\_\_\_\_\_
on; infestations
in; infections
Common routes of parasite entry are?
o Ingestion: o Skin or mucosal penetration: o Transplacental (prenatal) o Arthropod bite (vector): o Sexual contact
Virulence is dependent upon
Infective dose and exposure volume
pathogenesis is dependent upon
Penetration of anatomic barriers Attachment Cell and tissue damage Loss of nutrients Disruption, evasion, and inactivation of host defenses
true or false
Protozoa Multiply in hosts and
Helminths adult worms do not multiply in the definitive host.
Worms die over time, unless the host is re-exposed
The severity of disease is proportional to worm
load introduced into the host.
true for both
attachment of a parasite to a host can be done mechanically, molecularly or both?
both
some mechanical attachments or biting mouth parts of parasites to or into the host are the use of? name 5
Attachment mouthparts Oral cavity (capsule) Attachment organs Suction disk Biting mouthparts Direct penetration
damage to cells and tissues of the host can be done by?
mechanical damage
toxic products
immune pathogenic reaction
Mechanical tissue damage is done by a parasite to the host via.
Blockage of internal organs:
Pressure atrophy:
Migration through tissues:
Toxic Parasite Products that produce tissue damage can be categorized into 5 categories. what are they?
Destructive enzymes: Amoebic pore: Endotoxins: Catabolites: Toxic secretions:
Immune pathogenic reactions
that produce tissue damage can be categorized into 4 categories. what are they?
- Anaphylactic: Antigen + lgE, histamine
- Cytotoxic: Antigen on host cells, complement or
ADCC - Immune complex: Antibody complexes with extracelluar antigen
-C ell mediated: Sensitized T cells kill or release cytokines
a parasite ca cause a Loss of nutrients for the host can happen because of?
- Competition with hosts for nutrients
- Interference with nutrient absorption
- Nutrient loss
what is Natural or innate immunity?
A defense mechanism that does not depend upon prior exposure to the invader. this is achieved via
- Cytokines and cytokine receptors
• Antimicrobial molecules and pattern recognition
receptors
- Cellular defense, phagocytosis
Acquired immunity is?
conferred by a host’s
specific immunity response developed as a
result of a previous parasitic infection.
what is Premunition immunity?
resistance to reinfection
dependent on retention of the infectious
agent - malaria, toxoplasmosis
Concomitant immunity is?
immunity from 1 stage of a parasite but susceptible to other stages
- the survival of some cells or organisms with the immune
destruction of other cells or organisms of the same line-schistosomiasis
