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Parasitology > Exam # 1 > Flashcards

Exam # 1 Flashcards

1
Q

What is a parasite?

A

organism that lives on or in a host organism and gets its food from or at the expense of its host

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2
Q

What is parasitism?

A
  • is a form of symbiosis, in which the parasite, usually the smaller
  • symbiont, is metabolically dependent on the host.
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3
Q

What is the relationship between host and parasite?

A 
One symbiont (host) is harmed, while the other 
symbiont (parasite) benefits.
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4
Q

What are the characteristics of a parasite?

A
  • Depends on the host for survival
    • Has adverse effects on the host
    • Has greater fecundity than host
    • Is usually smaller than its host
    • Doesn’t want to kill its host
    host dies-parasite dies
    • In the case of Macroparasites
    (Helminths) – Are over-dispersed among the host population
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5
Q

How can a parasite harm a host?

A
  • Cause clinical/sub-clinical diseases
  • Trauma
  • Nutrient Robbing
  • Toxin production
  • Inflammatory responses/ Interaction with host immune
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6
Q

Why do we study parasites in veterinary medicine?

A
  • Impact animal health/welfare, Economic loss
  • Negatively impact the human-animal bond
  • Pose a challenge in wildlife conservation
  • Pose a risk to human health. Parasitic zoonoses
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7
Q

What is a direct life cycle?

A

Free living —> Host, no intermediate hosts

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8
Q

What is an indirect lifecycle?

A

Egg/Larvae in another host(s)–> host. Intermediate hosts present.

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9
Q

What is the lifecycle shown in this picture?

A

Direct lifecycle

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10
Q

What kind of lifecycle is shown in this picture?

A

Indirect

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11
Q

What is a microparasite?

A

E.g. Protozoa, Viruses (Malaria, Giardia, Toxoplasma)

  • Tiny, Unicellular, microscopic
  • Multiply within hosts
  • Short life cycles
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12
Q

What are macroparasites?

A

E.g. Roundworms, Tapeworms, Ticks, Fleas

Large, Multicellular, adult macroscopic

Reproduce in definative hosts

Generally longer life cycles

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13
Q

What are endoparasites?

A
  • Adults inside body of host
    eg: Nematodes, tapeworms, giardia
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14
Q

What are ectoparasites?

A

Parasites that live on the body of the host.

E.g. Ticks, mites, bugs, flies, mosquitos

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16
Q

What is an Obligatory parasite?

A

Only parasitic stage- no free living environmental stage

eg: trichinells spp. Plasmodium spp.

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22
Q

What are facultative parasites?

A
  • Both parasitic and non parasitic lifestyles
  • opportunistic parasite, can complete lifecycle without hosts.
    eg: strongyloides spp
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24
Q

What are Spurious parasites?

A

Incidental finding. Parasite is found in unusual host. Usually resulted from predation or accidental ingestion/ contamination.

Eggs/ larvae do not develop in unusual host

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25
Q

What is a pseudoparsite?

A
  • object or organism that resembles or is mistaken for a parasite.
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26
Q

What are the three major groups of parasites?

A
  • Protozoa
  • Helminths
  • Arthropods
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27
Q

How do protazoa reproduce and are they single celled or multicellular?

A

Single celled - microscopic • Reproduce mostly asexually -
Multiply and increase in number • Some sexually – fusion of
gametes
e.g. Giardia, Cryptosporidium Toxoplasma, E. coli

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28
Q

What is some important information on Helminths?

A

Multicellular – Adults easily visible • Produce offspring • Well developed organs, systems • Prepatent period and patency is
long
e.g: Hookworm, Tapeworms, Flukes

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29
Q

What is some important information about arthropods?

A
  • Multicellular – Visible
  • Segmented bodies, jointed limbs

• Parasites themselves or vectors
of other microbes

• Insects – 6 legs

• Arachnids 8 legs (adult)
e.g. Flies, ticks, mites

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30
Q

What is definitive host?

A

Main host. Supports sexual reproduction of the parasite. Parasite reaches
sexual maturity. E.g. Dogs for Toxocara canis

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31
Q

What is an intermediate host?

A

Supports the parasite’s development and asexual reproduction
(multiplication)—E.g. Slugs and snails for some lungworms.

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32
Q

What is a paratenic host?

A

Development, multiplication does not occur in this host. Help in
maintaining the lifecycle but not necessary. E.g., Rodents for some nematodes

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33
Q

What is a transport host?

A

Carrier of the parasite from one host to another. No development or
multiplication. E.g., Houseflies for some parasites. Aka mechanical hosts.

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34
Q

What is an aberrant/ unusual host?

A

Non-natural host. The parasite may cause pathology in aberrant hosts.
E.g., Dogs are aberrant intermediate hosts for Racoon roundworms.

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35
Q

What is a vector?

A
  • Carrier of an infectious agent between organisms of a different species. Can be
    intermediate hosts or transport hosts. Usually used in case of human infections. E.g., mosquitoes
    for heartworm, malaria.
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36
Q

What is a reservoir host?

A

Maintains the infection without being harmed—e.g., White-tailed deer for
brainworm.

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37
Q

What are the routes of transmission?

A
  • Fecal-oral- most intestinal parasites (Giardia, hookworms)
  • Skin penetration ( per-cutaneous)- bot fly
  • Vector transmission/ innoculation- heartworm via mosquitos
  • Direct contact : ectoparasites
  • Sexual transmission- Tritichomonas foetus
  • Vertical transmission: mother to offspring
    • Placental/ Prenatal (toxocara canis)
    • Through milk- Transmammary/ Lactogenic transmission (eg: ancyclostoma spp.)
  • Iatrogenic Transmission: Blood transfusion through contaminated surgical instruments, needles. (e.g. Blood protozoa, bacteria, virus)
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38
Q

How do you diagnose parasites?

A
  • Fecal test
    • Float, Sedimentation, Qualatative, Quantitative
  • Urinalysis- ex dioctophyme
  • Examination of blood
    • Blood protazoans, arthropods, and some helminths
    • Direct smear, stained smear, knotts test (HW disease)
  • Exam of tissue
    • Ex: Trichinella
    • Tissue digestion/ tissue squash
  • Exam of hair/ skin
    • Primarily ectoparasites. Ex: fleas mites, lice
    • Skinscrape, KOH digestion of scrape, direct observation.
  • Necropsy
    • Fatal cases
    • Adult parasites/ stages, characteristic lesions formed by parasites.
    • Histopathology
  • PCR/Genetic Markers
    • Species level ID
    • Primers/ probes used to amplify species specific genetic markers
    • can be done from extracted egg/larvae/ adult.
  • Immunological Tests: Elisa, IFA, CFT, ect.
    • Serological tests- tests for antibodies against parasites
    • In house testing
    • Commercial tests.
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39
Q

What are the important methods of parasite management or control?

A
  • Kill/Neutralize the parasites in the definitive hosts – Antiparasitic drugs
  • Prevent or reduce the production of offspring in the host
  • Immunization - Vaccines
  • Optimize host health to resist transmission
  • Kill/clear free-living stages in the environment
  • Prevent contact with/consumption of intermediate/paratenic hosts
  • Kill/neutralize intermediate/paratenic hosts

BREAK THE LIFECYCLE

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40
Q

What is a serious emerging issue in parasitology?

A

Drug resistance

  • Judicial use of paraciticides is critical
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41
Q

TRUE or FALSE: Arthropods are the smallest phylum in the animal kingdom?

A

False - they are the largest

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42
Q

What groups are encompassed within Arthropods?

A

Crustaceans (crabs, lobsters, shrimp), Arachnids (spiders, ticks, mites, scorpions), and Insects

(bugs, ants, bees, moths, flies, fleas, mosquitoes)

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43
Q

What are some problems caused by arthropods?

A
  • Annoyance
  • toxins/ Venom
  • Allergic Reactions
  • Invasion of host tissues/ trauma
  • Disease/ pathogen transmission
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44
Q

What are the important arthropod groups?

A
  • Arachnids and Insects
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45
Q

What are 2 groups within Arachnids?

A

Mites and Ticks

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46
Q

What is some important general information about arachnids?

A

2 distinct body parts – cephalothorax and
abdomen
• 8 legs attached to cephalothorax, no
wings or antennae
• Actively feed on host tissues and fluids at
some stage of their lifecycle

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47
Q

What are the 4 groups within Insects?

A
  • Hemiptera (Bugs)
  • Phthiraptera (Lice)
  • Siphonaptera (Fleas)
  • Diptera (Flies)
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48
Q

What is some important general information about insects

A

3 distinct body parts – head, thorax, abdomen
• 6 legs, 2 antennae, 2 pairs of wings attached
to thorax
• Actively feed on host tissues and fluids at some
stage of their lifecycle

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49
Q

What are some important characteristics of mites?

A
  • Dorsally flattened
  • small < 1mm
  • 6 legs as larvae to nymph
  • 8 legs as an adult
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50
Q

What are the features of mites that are diagnostically important?

A

l length of pedicel ( stalk connecting leg to caruncle) and caruncle (cup like sucker)

  • Chilicerca (feeding mouthparts)
  • Location of anus and anal plate
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51
Q

What are the two types of mites? What are some differences between them?

A
  • Burrowing mites- Short stumpy legs, circular shape, smaller than surface mites. They tunnel into skin.
    ex: Demodex
  • Surface mites- Long distinct legs, generally round to oval shape, larger than burrowing mites, remain on the surface
    ex: Otodectes
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52
Q

What is the lifecycle of mites?

A

Egg -> Larvae-> Nymph -> Adult

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53
Q

How are mites transmitted?

A

By contact (direct and indirect)

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54
Q

What symptoms/ issues can mites cause?

A
  • No effect to sever dermatitis (mange)
  • Hypersensitivities ( allergic reactions)
  • Excoriation and secondary bacterial infection.
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56
Q

What are some key features of ticks?

A
  • Dorso-ventrally flattened
  • Larvae 6 legs, nymph and adults 8 legs
  • Not very host specific
  • Sexual dimorphism obvious
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57
Q

What are Ticks?

A

Well-known vectors of human and veterinary pathogens (e.g Lyme, Ehrlichia etc.)

  • Most important in veterinary field **
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58
Q

What are some important features of Hard ticks?

A

Mouthparts visible when seen from above

• “Plate” on the back – Scutum

• Found in habitats rich with vertebrate hosts,
moist woodlands, forest edges, hiking trials

• More important (parasitize more people/animals
and more diseases in the US)

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59
Q

What are some important features of Soft ticks?

A
  • Mouthparts invisible when seen from above
  • Lack scutum – wrinkled body

• Found in animal burrows, dens. Can survive
hot and dry conditions

• Less common. Species of veterinary
importance are Ornithodorous spp., and
Otobius spp.

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61
Q

What is the lifecycle of 3 host tick?

A
  1. ) Adults will feed/ mate on third host
  2. ) Female will drop off host and oviposit
  3. ) Eggs will hatch and 6 legged larva will feed on first host.
  4. ) Larva will leave after feeding and then molt to nymph
  5. ) 8 legged nymph will feed on second host, then leaves and molts to adult
  6. ) Cycle repeats
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62
Q

What is the life cycle of the one host tick?

A
  1. ) Eggs hatch and 6 legged larva find host.
  2. ) Larva has 2 molts on host.
    - First molt to 8 legged nymph.
    - 2nd molt to adult on host
  3. ) Adults mate
  4. ) Female drops off host and oviposits
  5. ) cycle repeats
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63
Q

What is the action the tick is doing in this photo?

A

Questing- Host seeking behavior

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64
Q

What are the two types of ticks?

A

Hard ticks (Ixodidae) and Soft ticks (Argasidae)

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67
Q

What ticks are the most important in veterinary medicine?

A

Hard ticks and 3 host ticks

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71
Q

What are some issues ticks can cause?

A

All ticks can cause:

  • Anemia
  • Dermatitis, alopecia
  • Local bacterial infection of bites

Some ticks:

  • Paralysis: Salivary toxin of female tick
  • Pathogen transmission
  • Alpha-gal syndrome (red meat allergy)
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72
Q

What are some general characteristics of lice?

A
  • Dorso-ventrally flattened
  • 6 legs
  • High host specificity, also site specific
  • Divided into two main groups
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73
Q

What are the two types of lice?

A

Chewing/ biting lice (Mallophaga)

Sucking louse (Anoplura)

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74
Q

What are the key characteristics of Chewing/ biting lice? Sucking louse?

A

Chewing/ Biting Lice:

  • Wider head (wider than thorax)
  • Occurs mainly on birds, occasionally on mammals
  • Stout mandibles

Sucking Louse:

  • Head narrower than thorax
  • Nearly every mammal can be infested by sucking louse
  • Piercing mouthparts
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75
Q

What is the duration of the lifecycle of lice?

A

Entire lifecycle (20 – 40 days) on the host

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76
Q

How long can lice live off of the host?

A

Can live 2-3 weeks off the host but usually less than a week

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77
Q

How are lice transmitted?

A

Direct or indirect contact – Grooming instruments

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78
Q

When is infection more likely to occur with lice and what are the effects lice can have on the patients?

A
  • Infestation more common in the winter in northern climates – long
    hair
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79
Q

What are some key features of fleas?

A
  • Laterally flattened §
  • 6 legs
  • Not host specific
  • Lack wings but strong claws (attachment) and hind legs adapted for jumping
  • Chewing mouthpart
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80
Q

What is the diagnostic feature for fleas?

A

Shape of head and combs

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81
Q

What is the flea lifecycle? What conditions are optimal for growth/ survival of fleas?

A

Egg -> Larvae (1-3) -> Pupae -> Adult

Conditions: Warm and humid ( 75-90 degrees, 60-85 % humidity)

More Descriptive Life cycle:

  1. ) Eggs laid on hosts and are dislodged from the coat while shaking, scratching
  2. ) Development to larvae, pupae (inside cocoon) in the animal resting site.
  3. ) Larvae feed on flea poop “flea dirt”
  4. ) Adult hatch from cocoon when the host is nearby
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82
Q

What do flea larvae feed on?

A

Adult flea poop or “flea dirt”

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83
Q

What are some examples of Biting Flies?

A
  • Horsefly
  • deer fly
  • Horn fly
  • Stable fly
  • Black fly
  • Biting midge
  • Sand fly
  • mosquitoes
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84
Q

What are some examples of non biting flies (nuisance flies)?

A
  • Face fly
  • Head fly
  • House fly
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85
Q

What are some examples of myiasis causing flies?

A
  • Blowfly
  • Horse bot fly
  • Human bot fly
  • Nasal bot fly
  • Screwworm fly
  • Warble fly
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86
Q

What is the lifecycle of biting flies?

A
  1. ) Adult flies feed on horse
  2. ) After each meal, female lays eggs on ground with suitable substrate
  3. ) Eggs hatch in 12-24 hours to first instar larvae
  4. ) Larvae mature through three instars to pupae within puparia, then to adults within puparia.
  5. ) Adults emerge from puparia and can fly within an hour.

Life cycle completes within 12-20 days depending on environmental conditions.

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87
Q

What is the lifecycle of horse bot flies?

A
  1. ) Fly lays eggs no hairs, around legs, shoulders, neck and mouth.
  2. ) Horse injests eggs
  3. ) Eggs will attach to stomach / intestinal wall and grow into larvae (here they will live for 8-10 months)
  4. ) Larvae pass out in feces
  5. ) Larvae mature through three instars. Pupae withing puparia, and then to adults within puparia. This occurs in about 3-10 weeks.
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88
Q

When do adult fleas hatch from the cocoon?

A

When host is nearby.

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89
Q

What signs/ symptoms can effect patients with fleas?

A
  • Dermatitis
  • Flea bite hypersensitivity (Flea allergy dermatitis, FAD in dogs)
  • Anemia (rare, young animals)
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90
Q

What are some pathogens that can be transmitted by fleas?

A
  • Pathogen transmission:
  • Plague
  • Flea-borne typhus
  • Feline parvovirus
  • Tapeworms (D. caninum)
  • Nematode (A. reconditum)
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91
Q

What arthropod are these?

A

Flies

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92
Q

What is this arthropod?

A

Bug (Specifically bed bug)

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93
Q

What is this arthropod?

A

Fleas

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94
Q

What is this arthropod? Bonus: What is its scientific name?

A

Chewing/ Biting Lice

Bonus: Mallophaga

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95
Q

What is this arthropod? Bonus: What is its scientific name?

A

Sucking Louse

Bonus: Anoplura

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96
Q

What is this arthropod? What subtype is it?

Bonus: What family is it from?

A

Tick

Subtype: Hard Tick

Family: Ixodidae

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97
Q

What is this arthropod? What subtype is it?

Bonus: What family is it from?

A

Ticks

Subtype: Soft Ticks

Family: Argasidae

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98
Q

What is this arthropod? What is its subtype? Bonus : Example of one of them.

A

Mites

Subtype: Burrowing Mite

Example: Demodex

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99
Q

What is this arthropod? What is its subtype? Bonus : Example of one of them.

A

Mites

Subtype: Surface Mites

Example: Otodectes (Ear mites)

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100
Q

What is some general information about bugs?

A
  • Dorsoventrally flattened. Some bugs look like lice
  • Variable host specificity

– e.g Bed bug can bite both people and pets

  • Blood feeders
  • Bugs don’t live on people/pets, they bite host only when they need blood meal
  • Mostly feed at night, during day hide in crevices
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101
Q

What is the lifecycle of bugs?

A

Eggs ->Nymph (5 instars (stages) ) -> Adult

  • Bloodmeal is needed before each molt.
  • Adults can live for up to 1 year and can survive long period without feeding
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102
Q

What are some key characteristics of flies?

A

§ Important group of animal ectoparasites
§ Most have one pair of wings (adults)
§ Greatly vary in size, colour, food preference and
developmental stage that parasitize animals.
§ Adults feed on blood, saliva, tears, mucous of
hosts

§ Vectors and Intermediate hosts for many
pathogens microparasites
§ Larval stages may cause myiasis (s/c tissue,
respiratory track or GI track

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103
Q

What are the 3 types of flies and what is some general information about each?

A
  1. ) Biting fly - Damaging stage is adult fly, blood sucking.
    - Scissor like mouthparts
  2. ) Non- biting (nuisance flies)- can cause nuisance and stress.
    - Mouthpart has soft, spongy structure called labella and proboscis.
  3. ) Myiasis causing flies- Damage caused by maggots (larvae) that feed on host tissues. Adults are non biting.

ALL CAN TRANSMIT DISEASES

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109
Q

What is the pathogenesis of flies?

A
  • Harassment (common)
  • Anemia (rare)
  • Dermatitis/local infection
  • Hypersensitivity
  • Organ-specific damage
  • General tissue necrosis
  • Pathogen transmission
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110
Q

List the arthropods in order of decreasing host specificity.

A

Lice

Mites

Fleas

Ticks

Flies

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111
Q

How do you diagnose arthropod parasites?

A
  • Morphology of adult/ larval/ egg stages
  • Skin inspection
  • Ticks/ flies - easily visible (remove intact organism and look at with disecting microscope)
  • Examine third instar larvae of flies- spiracular plate
  • Mites- skin scraping- superficial/ deep
  • Tissue digestion using 5% KOH (for mites during deep scraping)
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121
Q

Why are arthropods an important group of ectoparasites?

A
  • Intermediate hosts for other parasites and vectors for micro-parasites
  • Very successful and adaptable – high reproductive potential
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122
Q

What are some arthropods that cause allergic reactions?

A

Bites or stings by lice, bugs, fleas etc

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123
Q

What are some arthropods that cause disease/ pathogen transmission?

A

Kissing bugs – Chagas disease

Mosquitoes - dog heartworm

Ticks - Lyme, Anaplasmosis, ect

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124
Q

What is the consequences of arthropods that invade host tissue?

A
  • Cause trauma
  • Invade the body tissue of the host
  • Fly larvae invasion – Myiasis
  • Dermatitis, pruritus (itching
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125
Q

How long does it take a mite to go through an entire life cycle? Where does it take place?

A
  • Entire lifecycle completes on the host.
  • Length of life cycle varies, few day (Sarcoptes) to weeks
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126
Q

How long can mites last in the environment?

A

Environmental survival limited (Only some species can survive few weeks outside the host)

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127
Q

What is a consequence of infection of lice?

A
  • Pediculosis – Pruritus, alopecia, excoriation, hair loss, anaemia
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128
Q

Fleas can be intermediate hosts to what ?

A

Some nematodes

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129
Q

How are bugs transmitted?

A

Through contact. They live mostly in the environment, in crevices

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130
Q

What are helminths?

A

Worms! Invertebrates, Macroparasites

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131
Q

What Phylum do roundworms belong to?

A

Nematodes

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132
Q

What Phylum do Flatworms belong to?

A

Platyhelminthes

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133
Q

What phylum do thorny- headed worms come from?

A

Acanthocephala

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134
Q

Platyhelminthes can be divided into 2 classes. What are they and what is the common name of those within them?

A

Cestodes (tapeworms) and Trematodes (flukes)

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135
Q

Where can you find Nematodes?

A

Present in every imaginable habitat. Arctic, Soil, Deep Sea, ect

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136
Q

TRUE or FALSE: Nematodes are Coelomates?

A

No they are pseudoceolomates

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137
Q

What is the target of antihelmintic drugs?

A

Nerve function. It is necessary to survival for nematodes

138
Q

What are key features of nematodes?

A
  • chitinous cuticle, presence of complete digestive system. - Sexual dimorphism, Reproduce sexually
139
Q

Which nematode does not reproduce sexually?

A

Strongyloides

140
Q

Male nematodes have what reproductive structure and what is it for?
BONUS: What is the structure made out of?

A

Males have copulatory bursa for grasping females, and copulatory spicules for guiding sperm.
Bonus: It is made out of a cuticle modification.

141
Q

What are the 3 cuticular modifications in nematodes?

A
  • Various size/ shape of buccal cavity
  • leaf crown/ alae
  • Copulatory bursa
142
Q

Which nematodes have a large Copulatory bursa?

A

Strongyles

143
Q

What is the infective state of nematodes?

A

L3 and sometimes L1

144
Q

What is the adult stage of nematodes referred to?

145
Q

Where are eggs shed from the nematode in regard to the host?

A

L1 in feces (sometimes in urine), some dont shed at all

146
Q

What is the most common migration of nematodes?

A

Hepatic-Tracheal migration

(ascarids)

147
Q

What are critical external components for larval/ egg development?

A

Temperature and Humidity

148
Q

What is hypobiosis?

A

-Inhibited larval development to avoid adverse conditions for development and
maturation – adaptation to host and environmental conditions
- Development starts once condition become favorable

149
Q

How do you diagnose infections of nematodes?

A
  • Morphological identification
  • Identifying eggs/ larvae
  • Molecular/ serological testing.
150
Q

What are the 6 major nematode orders?

A
  1. ) Strongylida
  2. ) Rhabditida
  3. ) Ascaridida
  4. ) Oxyurida
  5. ) Spirurida
  6. ) Adenophorea
151
Q

What is the segments of the cestodes body called?

A

Proglottids

152
Q

What are some unique features of cestode anatomy?

A
  • Flatworms - dorsoventrally flattened body.
  • Tiny (2 mm) to enormous (12 m)
  • Segmented body (Proglottids) 3 to 100s
  • Head with suckers (slit/cup like) - attachment or Bothria
  • Hemaphrodite
  • Acoelomate
  • Alimentary canal absent - feed by absorption
  • Body covered by tegument
  • Indirect life cycle
153
Q

What kind of lifecycle do cestodes have?

A

Indirect. Most vertebrate intermediate hosts/ some arthropods.

154
Q

What are two important orders of cestodes?

A

Cyclophylidea
Pseudophylidea

155
Q

Within Cyclophylidea, what are the categories of tapeworms of veterinary importance?

A

Taeniid tapeworms:
- Taenia spp.
- Echinococcus spp.
Non taeniid tapeworms:
- Dipylidium
- Mesocestoides
- Moniezia
- Anoplocephala

156
Q

What are the two important genus’s of pseudophylidea?

A
  • Diphyllobothrium (fish tapeworm)
  • Spirometra (tapeworm of dog, cats and wild
    carnivores)
157
Q

What are two important characteristics of cyclophylidea?

A
  • Organ of attachment: Suckers
  • Eggs are non operculated
158
Q

What are two important characteristics of pseudophylidea?

A
  • Organ of attachment: Bothria
  • Eggs operculated
159
Q

How many intermediate hosts do pseudophyllidean cestodes usually have?

A

2 intermediate

160
Q

What kind of larvae do cestodes have?

A

hexacanth larvae

161
Q

What are cestodes infective larvae called?

A

Metacestode in final intermediate hosts.

162
Q

What kind of cestode eggs are these?

A

All Taenia species have same egg morphology.

The eggs have an embryo with 6 hooks (hexacanth larvae) and thick straited egg shell

163
Q

What kind of cestode eggs are these?

A

Operculated eggs

Diphyllobothrium and Echinococcus spp. ) have same egg Spirometra morphology – commonly called taeniid eggs. Moneizia
(note, most trematodes have operculated eggs too)

166
Q

What are tapeworms named according to?

A

Morphology of the cyst

167
Q

What are the names of tapeworms cysts?

A
  1. Cysticercus
  2. Cysticercoid
  3. Hydatid
  4. Coenurus
  5. Strobilocercus
    Cysticercus – A single protoscolex in a fluid filled cyst
    Hydatid cyst
  6. Plerocercoid
  7. Tetrathiridum
168
Q

What is the adult morphology of trematodes ?

A

Flat, leaf like body

Easily visible

hermaphrodite

Two suckers (Oral and ventral)

169
Q

What kind of lifecycle do trematodes have?

A

Lifecycle is always indirect. Most have 2 hosts, some have 3 hosts (2 IHs)

170
Q

What intermediate host must always be present in trematode lifecycles?

A

a snail ( terrestrial or aquatic)

171
Q

What environmental factor is extremely important in the life cycle of most trematodes?

172
Q

What is the name for the infective stage for most trematodes?

A

Metacercaria

173
Q

Where do trematodes typically infect in the host?

A

Definitive host: may infect GI tract, Liver, Lungs, circulatory system

174
Q

What kind of eggs do trematodes have?

A

Eggs are operculated except heterobilharzia)

175
Q

What is a unique feature of fluke eggs is important to know?

A

It doesnt float. Sedimentation method is important

176
Q

What is key morphology of acanthocephalans?

A
  • No digestive tract, separate sexes, retractable spiny attachment (Proboscis)
177
Q

What kind of lifecycle do acanthocephalans have?

178
Q

what is the intermediate host for acanthocephalans

A

Arthropods (beetles)

179
Q

TRUE OR FALSE:Ancanthocephalans are a very common group of parasites

180
Q

In Acanthocephalans, how are nutrients absorbed?

A

No digestive tract. Nutrients absorbed through tegument.

181
Q

What parasite is this?

182
Q

What is the image pointing at? Hint: This is a nematode

183
Q

What parasite is this cross section from?

A

Nematode or roundworms

184
Q

What is this image of overall? What parasite is it from? and What are the red lines pointed at?

A
  1. ) Buccal Cavity
  2. ) Nematode
  3. ) Teeth
185
Q

What are the projections (indicated with the black arrow) in this photo?

A

Cervical Ale

186
Q

What kind of parasite is this?

A

Trematodes

187
Q

What kind of parasite is this?

A

Thorny headed worm or Acanthocephalans

188
Q

Recap

189
Q

Where are Acanthocephalans found?

A

Vertebrate digestive tracts

190
Q

What is an important note for Acanthocephalan eggs?

A
  • eggs are very heavy and contain larvae
199
Q

Nematode development can be completed where?

A

Entirely at the predilection site.

Larvae/pre-adults can also migrate during development

200
Q

Nematodes that generally develop ONLY in the gut are ?

A

Generally asymptomatic with low pathogenicity.

201
Q

Where do larvae migrate to in the case of tracheal ascarid?

A

Larvae will migrate to the liver, lungs, and heart.

Can cause hepatic damage, respiratory signs, lung lesions, etc.

202
Q

Name the two morphological factors that help differentiate between Nematode eggs:

A

Egg shape

Egg shell thickness

203
Q

Give an example of nematodes with thick egg shells?

A

Astarids

Tape worms

204
Q

Give an example of parasites with thin egg shells?

A

Hookworm, Strongyloides

205
Q

What is spring rise?

A

Spring rise is the build of larvae of the egg during the spring

206
Q

What is periparturient?

A

When the immune system is compromised during parturition → increased number of eggs/larvae

207
Q

Where can adult Nematodes be found?

A

In vomit and feces.

208
Q

How can you ID Nematode eggs/larvae in feces ?

A

Eggs = fecal smear, flotation, sedimentation

Larvae = Baermann method (larval sedimentation)

209
Q

The entire head of a Cestode is called a?

210
Q

The parasite that causes these lesions can travel a considerable distance before settling in their predilection site, what are they?

A

Larva Migrans

211
Q

In case of Pig ascarid, larval migration from the intestine on to the liver and the lungs can cause what kind of damage to the pig?

A

hepatic damagerespiratory signs, lung lesions

212
Q

What does the scolex give rise to?

A

The proglottids

213
Q

How is being a hermaphrodite beneficial for Cestodes?

A

Cestodes can self fertilize and cross fertilize.

214
Q

What does Acoelomate mean?

A

Lacking a coelum/body cavity.

215
Q

What is the opening indicated by the arrow called? What is it for? What phylum and order are they found in?

A

Bothria

Function: Organ of attachment

Phylum: Cestode

Order: Pseudophylidea

216
Q

What is the main function of the Cestodes Tegument?

A

The tegument’s main function is nutrient absorption.

217
Q

What is the main difference between Taeniid tapeworms and Non-taeniid tapeworms?

A

Egg morphology differs.

218
Q

Define Hexacanth.

A

Hexacanth

Canth = small hooks

Hexa = 6

Usually can count 6 hooks in the egg.

219
Q

Describe in detail the life cycle of the Cestode.

A
  1. Larva develop into adults in the intestine of the definitive host
  2. Egg with hexacanth larvae form in the definitive host
  3. Contaminate feces (environment)
  4. Egg with hexacanth larvae OR gravid proglottids (environment)
  5. Ingested by intermediate host; eggs change into oncosphere; penetrate gut wall and reach various tissues.
  6. Larvae (metacestodes) form cysts in various tissues (intermediate host)
  7. Ingestion of intermediate host tissue with cysts containing infective larvae enter new definitive host
  8. Cycle starts again
220
Q

Cysticercus is a ?

A

Single protoscolex in a fluid filled cyst.

221
Q

Metacestodes are named according to?

A

Morphology of cysts.

222
Q

What kind of lifecycle do nematodes have?

A

Direct lifecycle, indirect lifecycle, oviparous, viviparous, ovoviviparous, obligatory,
facultative

225
Q

What are oncospheres?

A

A hatched hexacanth

226
Q

What stage of development is L5 in nematodes?

227
Q

What is contained within each proglottid?

A

A male and female reproductive system

230
Q

Is Protozoa multicellular or unicellular? What else is important about them?

A

Unicellular
- single celled, distinct nucleus, microscopic, with greater complexity than other unicellular forms ( bacteria)
- Each protozoa possess specialized organelles
and function as independent organism

231
Q

Are most Protozoa pathogenic?

A

Most are free living and are not pathogenic but some co-
exist with animal hosts (parasitic protozoa)

232
Q

What is the life cycle of Protozoa?

A

Life cycle – direct (e.g Eimeria) or indirect (e.g Sarcocystics, Trypanosoma)

233
Q

What kind of reproduction is seen in Protozoa?

A

Asexual (e.g Giardia) or alteration of sexual and asexual lifecycle (e.g Toxoplasm

234
Q

Do Protozoa gravitate to a specific host?

A

Varied host specificity – High (e.g Sacocystics, Eimeria) or low (e.g Cryptosporidium)

235
Q

What is the pathogenicity caused by protozoa?

A

Pathogenicity is caused either by destruction of host cells, toxins or by changes in host immune
system

236
Q

What is an important consideration for protozoa?

A

Important to consider zoonotic potential

237
Q

What is important to remember when trying to control, diagnose, and treat protozoal infections?

A
  • Control requires knowledge of complete lifecycle
  • Diagnosis – Morphology, Serological and molecular
  • Treatment may not kill all stages
238
Q

What are the four groups of Protozoa of veterinary importance? What are they grouped by?

A

Flagellates
Amoebas
Ciliates
Apicomplexans

They are grouped based on their locomotion

239
Q

What is some important characteristics of Flagellates?

A
  • Locomotion by flagella
  • Mucosoflagellates (Direct life cycle, ex: giardia)
  • Haemoflagellates (Arthropod transmitted, ex: trypansoma)
240
Q

What is some important characteristics of Ameobas?

A

Locomotion by pseudopodia

  • Direct life cycles
  • Ex: Naegleria fowleri, E. Histolytica
241
Q

What is some important characteristics of Cillates?

A

Locomotion by cillia

  • Direct life cycles
  • Eg. balantidium coli
242
Q

What is some important characteristics of Apicomplexans?

A

Locomotion by gliding

Coccidia:

  • Direct life cycle (Ex: elmeria, crypto)
  • Indirect life cycle (Ex: Toxoplasma)

Haemosporida

  • Arthropod transmitted (Ex: Babesia)
247
Q

What is the morphological characteristics of muscoflagellates?

A
  • Pear shaped
  • Most have direct life cycle
  • e.g Giardia, Tritrichomonas spp. – direct lifecycle
  • Histomonas – Indirect lifecycle ( transmitted by another
    parasite)
    Two stage: Cyst and Trophozite ( only stage in Trypansoma)
248
Q

In Muscoflagellates, what are the key differences between Trophozoites and cysts?

A

Trophozoite
• Active motile form

• Vegetative form – divides by binary
fission

• Doesnot survive well in the
environment

• Only stage in Trypanosoma

Cyst
• Non-motile

• Environmentally resistant stage

• Can survive for months in wet and
cool conditions

249
Q

In muscoflagellates, what is a more simple breakdown of trophozoite vs. cyst stages?

A

Trophozoite stage is the feeding stage of the protozoan. Cyst stage is the dormant, resistant infectious stage of the protozoan

250
Q

How are hemoflagellates transmitted?

A

Arthropod transmitted

251
Q

Where are hemoflagellates found?

A

Lie in blood/ tissues of animals/ humans

252
Q

What are the 3 different forms of hemoflagellates and what makes them differ from one another?

A
  • Amastigote – Mammalian intracellular form
    No flagella or undulating membrane
  • Promastigote – Arthropod gut form
    Long flagella, spindle shaped body
  • Trypomastigote- Mammalian blood form
    Long flagella, spindle shaped body
253
Q

What are apicomplexans? What are some key characteristics?

A
  • Obligate intracellular pathogens
  • Designed to get inside cells – Apical complex (organelle for invasion)
  • Complex lifecycle – Direct (D) or indirect (I)
  • Life cycle alternates between sexual and asexual reproduction
254
Q

What are 3 types of apicomplexans?

A
  1. ) Intestinal (coccidia)
  2. )Systemic
  3. ) Blood
255
Q

What kind of life cycle do intestinal apicomplexans have and what are some examples?

A

Direct Lifecycle (Examples: Cryptosporidium, Eimeria, Cystoisospora)

256
Q

What kind of life cycle do Systemic apicomplexans have and what are some examples?

A

Indirect lifecycles ( Toxoplasma, Neospora, Sarcocystis)

257
Q

What kind of life cycle do blood apicomplexans have and what are some examples?

A

Indirect- Arthropod transmitted

(Ex: Babesia, Cytauxzoon)

258
Q

What are the steps to the lifecycle of intestinal coccidia?

A

1.) Dog is infected (sporulated oocysts of isospora enter the gut)

2.) The shell of the oocyst Sexual reproduction breaks down and (GAMETOGONY) – releases parasitic production of male and sporozoites, which female gametes and penetrate intestinal fusion, resulting in epithelial cells
fertilized zygote

  1. ) Asexual Reproduction (Merogony)
  2. ) Sexual reproduction breaks down and (GAMETOGONY) – releases parasitic production of male and sporozoites, which female gametes and penetrate intestinal fusion.
  3. ) Zygote is created
  4. )Zytoge developes into an oocyst that exits the canine host in feces
    (6) the oocysts sporulate (SPOROGONY) in the environment in a few days and becomes infectious to new dogs.
259
Q

What is the lifecycle of systemic coccidia (toxoplasma)?

A

Asexual (merogony) and sexual
(gametogony) phase in definitive hosts

  • Only asexual (division, multiplication) in
    Intermediate hosts
  • Only for toxoplasma, transmission can
    occur between intermediate hosts!
  • For other systemic coccidia (Sarcocystis,
    neospora)
  • transmission to definitive hosts occurs
    by ingesting the cysts in the tissue of
    the IH, and - transmission to IH occurs via ingestion
    of sporulated oocyst!
260
Q

What is the lifecycle of blood apicomplexa?

A

Ex: Babesia Canis

  1. ) Tick has blood meal from infected animal, and sporozoites remain in the salivary glands of ticks.
  2. ) Sexual reproduction of protazoa occurs within the tick, and tick takes bloodmeal from new host.
  3. ) New host is innoculated via bite.
  4. ) Asexual reproduction occurs within the hosts erythrocytes.

Cycle repeats.

261
Q

What is a rare way blood ampicomplexans can be transmitted, other than through an arthropod vector?

A

Iatrogenic transmission is also possible
through blood transfusion or blood- contaminated fomites.

262
Q

How can you diagnosis a protozoal infection? What does each test detect?

A
  1. ) Fecal testing- microscopy (fecal float/ smear for intestinal protozoa)
    - can detect f cysts, torphozoites, oocysts in feces (quick diagnosis in clinical cases)
  2. ) Blood testing- Direct smear, stained smear (Blood protozoa are specific on the types of blood cells they infect!)
  3. ) Serological/ Molecular methods
    - Examination of blood/ serum for Antibody against parasites (serology)
    - Examination of feces for parasite/ antigen ( active infection)
    - Extracting DNA of the parasite and sequencing- High accuracy.
263
Q

Why test for parasites?

A
  • Tailor therapy/ prophylaxis for individuals.
  • Detect developing resistance
  • Reduce unnecessary use of medications in low risk population’s.
  • Detect emergence of new parasites especially with warming climate.
264
Q

Who needs parasitology testing?

A
  • Clinically ill ( Diarrhea, vomiting, bloody stool, anemia, eosinophilic enteritis, coughing, once bacteria/ virus r/o)
  • High risk animals ( young, high exposure, susceptible such as immunocompromised, pregnant, old, young, nursing)
265
Q

What is the definition of the word Prevalence?

A

Proportion of animals (%) infected with a parasite

266
Q

What is the definition of Intensity of infection?

A

Number of parasite/parasitic stage in an individual animal
• Usually expressed in eggs/oocyst/larva per gram of feces • When expressed as mean/median of a herd/population only positive
animals are considered

267
Q

What is the definition of sensitivity?

A

The ability of the test to correctly detect individuals infected with a parasite

(true positives)

268
Q

What is the definition of specificity?

A

The ability of the test to correctly detect individuals without a parasite (true
negatives?

269
Q

What is the definition of a pseudoparasite?

A

an object or organism that resembles or is mistaken for a parasite

270
Q

What kind of tests can be run on fecal samples?

A
  • Fecal smear
  • Fecal flotation
  • Fecal sedimentation
  • Baermann method
  • McMaster method/ FLOTAC
  • Coproculture (Fecal culture)
271
Q

What are the most important things to remember when doing a fecal examination?

A

• Important to have fresh samples, preferably directly collected from the animal
• At least 10 g of feces should be collected
• Feces collected from yard, pen or litter box may be old and egg may embryonate, oocyst
may sporulate
• Refrigerate (4 degree C) to prevent development
• Freezing is inefficient – freeze thaw destroys eggs/larvae

272
Q

What is a direct fecal smear and what are the pros and cons?

A
  • Qualitative fecal exam
  • Simple quick and easy
  • Good for moving protozoal trophozoites (giardia), mobile amoeba
  • Can be fixed with a special stain (e.g for Cryptosporidium)
  • Negative result inconclusive, positive result equally valid!
273
Q

What is a fecal flotation and what is the most important thing to remember when preforming the test?

A
  • Based on differential specific gravity of parasite eggs/cysts, fecal debris and flotation solution.
  • Flotation solution must have higher specific gravity than parasite eggs or oocysts.
  • Specific gravity of most parasite eggs are 1.1 – 1.2 g/ml
  • Flotation solutions should be > 1.2
274
Q

What parasite would a fecal float be best used for?

A
  • Best for most nematodes and cestode eggs, some protozoal (oo)cysts
275
Q

What happens if you use a solution for fecal float that is too low in specific gravity? To high?

A
  • Some fluke eggs won’t float especially if solutions of lower specific gravity are
    used
  • Higher specific gravity solution – distorts protozoal trophozoite, cysts and
    some helminths eggs, larvae – Proper choice of flotation solution
276
Q

What is the ideal specific gravity of a fecal float solution?

277
Q

What are the steps to complete a passive/ standing fecal float?

A
  1. ) Feces + flotation solution in beaker / cup.
  2. ) Strain and transfer into test tube/ fecalizer
  3. ) Add coverslip and let it stand for some time
  4. ) Examine coverslip under microscope
278
Q

What are the steps to complete a centrifugal fecal flotation?

A
  1. ) Feces + flotation solution in a beaker/ cup
  2. ) Strain and transfer to test tube
  3. ) Add coverslip and centrifuge ~ 1500 rpm for 5 minutes
  4. ) Examine coverslip under microscope
281
Q

What are the pros and cons of using a passive/ standing fecal flotation?

A

Pro:

  • Simple and Fast
  • Commercial kits available

Cons:

  • Lower sensitivity
  • Qualitative or semiqualitative.
282
Q

What are the pros and cons of using centrifugal fecal flotation?

A

Pro:

  • Recovers more eggs/ ova
  • Higher sensitivity
  • Can be quantitative

Con:

  • More labor intensive
  • More expensive
283
Q

What is most important to remember when deciding between a passive/ standing fecal floatation or a centrifugal fecal flotation?

A

Centrifugation increases the sensitivity of your tests. Centrifugation recovers 3-5 times as many eggs over other passive floatation techniques

284
Q

What is the McMaster Method?

A
  • Commonly used quantitate technique for helminth eggs in
    livestock
  • It uses a counting chamber that enables a known volume of fecal
    suspension to be examined microscopically
  • Based on the principle of passive flotation (no centrifugation
    required)
  • Quantitative
285
Q

What is the steps to preforming the McMaster method?

A
  1. ) The fecal slurry is made with a known amount of feces and a known amount of flotation solution
  2. ) The slurry is sieved through a strainer
  3. ) Filtrate is used to fill the counting slide chamber
  4. ) Calculation (according to the protocol)
286
Q

What is the Wisconsin double centrifugation?

A

Sensitive test that has 2 centrifugation steps, it is quantitative.

Most sensitive flotation technique in low
infection intensities (1 epg or less)
287
Q

What are the two centrifugation steps in the wisconsin double centrifugation?

A

Two centrifugation steps

  • 1st – Fecal slurry made up of feces and water
  • 2nd – Sediment of 1st step homogenized with flotation solution
288
Q

Why is the wisconsin double centrifugation test challenging in clinics?

A
  • Requires larger space (centrifuges)
  • More time
  • Expensive
289
Q

What is fecal sedimentation and when would it be used?

A
  • For eggs with higher specific gravity (e.g trematodes and acanthocephalan eggs) that do not float easily or eggs that are easily distorted by flotation solution
  • More sensitive than direct smear
290
Q

What are the steps to the traditional sedimentation method?

A

Mix 10 g of feces with 100 ml of water

  1. ) Mix and strain, collect filtrate in a beaker
  2. ) Allow to sediment for 5 minutes
  3. ) Allow to sediment for 5 minutes
  4. ) Siphon off supernatant
  5. ) Examine the sediment
291
Q

What is the Baermann method? What would be a parasite this would be an ideal test for?

A
  • For parasites that shed larvae in the feces (e.g. Dictyocaulus, lungworms)
  • Feces suspended in water overnight -> Migration of live larvae out of the fecesinto water
  • Should only be used in fresh feces (live larvae)
292
Q

What is a coproculture (fecal culture)? What is it used for?

A
  • Eggs of strongyles/trichostrongyles are virtually impossible to
    diagnose morphologically so eggs are grown in a culture
    medium (vermiculite) at room temperature for several days to
    the third stage larvae (L3)
  • L3s are morphologically distinguishable
  • Usually done in pooled samples
293
Q

What are the steps to a coproculture?

A
  1. ) 20-30 grams of feces + tap water vermiculate
  2. ) Incubate at room temperature, maintain moisture
  3. ) After 7-14 days Larvae recovered (Baermann technique)
  4. ) Microscopy
294
Q

What are the limitations of fecal based diagnosis?

A
  1. ) Chances of false negatives
  2. ) Chances of false positives
295
Q

Why may there be false negatives on fecal tests?

A
  • Sporadic shedding
  • Prepatent period – Parasites not yet mature to shed eggs/larvae
  • Single-sex nematode infections
  • Senescent infections
  • Old feces (hatched eggs)
296
Q

What is a false negative test?

A

Negative test result but the host has parasites

297
Q

What is a false positive test?

A

Positive test result but no parasitism

298
Q

Why may there be a false positive on fecal tests?

A
  • Coprophagia/Predation – Spurious
    parasites
  • Pseudoparasites
  • Many parasite species shed identical eggs – Diagnostic challenge
299
Q

What is a direct blood smear? What kind are there?

A

S implest blood parasite detection procedure is by direct microscopic examination of whole blood.

  • Thick smear
  • Thin smear
300
Q

What is a thick bloodsmear and what is a parasite it is good to use for?

A

o Examining a drop of blood on a slide
o Mainly for motile microfilariae of D. immitis
o Quick and easy method but less reliabl

301
Q

What is the Modified Knotts test used for?

A

Rapid detection and identification of microfilariae (larvae) of filarial nematodes in
blood
- Concentrates microfilaria from 1 ml of blood à more sensitive

302
Q

What is a thin bloodsmear and what is a parasite it is good to use for?

A

o A drop of blood spread on the slide
o Not suitable for microfilaria larvae
o Suitable for Trypanosomes, Babesia, Thelaria, Anaplasma

303
Q

What is superficial skin scraping? What wouls you use it for? Where should you scrape?

A
  • On animal with pruritic or scaly skin ( Scabis, Cheyletiella, Otodectes etc.)
  • The best areas to scrape are typically crusty ear margins and crusty areas on the elbows or hocks.
304
Q

What is deep skin scrapping? What is a parasite this is used for, and what is the process to take a deep skin scrape?

A

For mites that reside deep in the hair follicle (E.g. Demodex )

  • Squeeze the skin
  • Scrape unitl there is light capillary bleeding – multiple sites
305
Q

What is the steps for thin blood smears?

A
  1. ) Make slide ( Make blood smear, you know how to do this)
  2. ) Fix in methanol for 2 minutes
  3. ) Stains ( Giemsa, fields stain)
307
Q

What is tissue digestion used for? What are the general instrictions? What is an example of a parasite you can use this for?

A
  • For parasites that have their larval or adult stages in host tissues and organs
  • Tissue is digested in digest solution (mostly acid pepsin) at a certain temp for certain time -> centrifugation -> digest examined
    (e. g – Trichinella spp., some arthropods)
308
Q

What is the peri-anal tape method? What are its pros and its cons?

A
  • Preferred method to detect eggs of pinworms in large animals
  • Eggs often attach to perianal region and may not been present in the feces
  • In dogs/cats- used to detect segments and eggs of cyclophyllid cestodes (e.g Taenia spp.)
  • Risky technique in regions where Echinococcus spp. is endemic.
309
Q

What can be used to diagnose ectoparasites?

A
  • Skin scrapping KOH digestion

• Collection and examination

312
Q

What are coproantigen tests? What is an example?

A

Coproantigen tests: Parasite antigens in feces Increasingly common for in-house detections (e.g cyst wall antigen for Giardia in dog/cat feces)
Example: Blood antigen test – E.g. 4dx snap test (IDEXX)

Coproantigen ELISA exists for Ascaris, hookworms, giardia.

313
Q

What immunological tests are available for protozoal infections?

A

Antibody tests – Protozoal infections

  • Complement fixation test
  • Immunodiffusion
  • Haemagglutination test
  • Florescent antibody test
314
Q

What is KOH digestion? What/ when is it used for?

A

If the scrapping contains much debris § If lice/mites are suspected and not found by inspection

315
Q

What are the steps to KOH digestion?

A
  1. ) 1 volume of skin scrappings + 10 volumes of KOH in large beaker
  2. ) Heat until hair disolves
  3. ) Centrifuge and transfer the sediment to a petridish and observe under microscope at 10x ( you can see mite eggs, mites, and lice with this)
318
Q

What are immunologic tests against parasites? What is an example of one?

A 
Detecting antibodies (against the parasites) and antigens (of the parasites)
• ELISA – testing serum antibodies against parasites, parasite antigens
319
Q

What are the strengths of Immunologic testing for parasites?

A
  • Can identify presence of parasites when eggs are not recovered by flotation (e.g prepatent infection, intermittent egg shedding)
  • Relatively simple, fast (commercial kits)
320
Q

What are the limitations of immunological testing of parasites?

A
  • Measures immune response to exposure – not necessarily active infection
  • Cross-reactivity
  • Not universally available
323
Q

What are PCR tests for parasites?

A
  • Extraction of parasitic DNA from eggs/larvae in feces (Copro PCR); blood or tissue stages, or adult stage
  • Amplification of a specific genetic marker/gene or genes
  • Analyzing the DNA sequence to ID the species
324
Q

What is the Advantages of PCR parasite testing?

A
  • Higher Sensitivity ( copro pcr than egg based method)
  • Accurate
  • Sequences for species level ID, genotyping, phylogenetics
325
Q

What are limitations of using PCR testing for parasite identification?

A
  • Not possible in clinics
  • Expensive, Highly technical

Parasitology (10 decks)

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