Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Parasitology > Chapter 6 > Flashcards

Chapter 6 Flashcards

(63 cards)

Start Studying
1
Q

What disease does cryptosporidium cause

A

cryptosporidiosis- diarrheal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What type of organisms does cryptosporidium infect

A

humans-often children and AIDS patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What was the worst cryptosporidiosis outbreak in the US

A

Milwaukee 1993- 400,000 people

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the symptoms of cryptosporidiosis

A

watery diarrhea, dehydration, weight loss, abdominal pain, fever, nausea vomiting, severe to immunocompromised, mostly SI also other digestive organs and lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How are cryptosporidium diagnosed

A

acid fast staining, immunofluorescence microscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is Cryptosporidiosis treated

A

electrolytes, nitazoxanide for immunocompetent, no guidance for immunocompromised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain the cryptosporidium life cycle

A
  1. thick walled oocyst (sporulated) exits host
  2. contaminated water and food with oocysts come into contact with humans, in drinking water
  3. thick walled oocyst ingested by human
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does cryptosporidium leave its host and what stage is it on when it does so

A

sporulated oocysts with 4 sporozoites leave through feces or possibly respiratory secretions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is cryptosporidium transmitted to humans

A

contact with contaminated water, recreational or drinking, can be zoonotic when exposed to infected feces of animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Once ingested by a human, what stage is cryptosporidium on and what does it do

A

after ingestion, excystation, where sporozoites are released and attack epithelial cells of GI tract or tissues in respiratory tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Explain when and how cryptosporidium undergo asexual multiplication and sexual multiplication

A

In infected cells of the GI tract or respiratory sys. schizogony/merogony-asexual then
gametogony-sexual producing micro (M) and macro (F) gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What occurs in the cryptosporidium life cycle after asexual and sexual reproduction

A

once macrogamonts are fertilized, they develop into oocysts that sporulate in host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What types of oocysts are produced in cryptosporidium

A

thick walled- often excreted from host

thin walled- usually for autoinfection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is special about oocysts of Cyclospora cayetanensis

A

they are unsporulated when excreted and do not become infected until sporulation is completed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the symptoms of cyclosporosis and what is the incubation period

A

incubation- 1 week
watery diarrhea, can be explosive, anorexia, weight loss, abdominal pain, nausea and vomiting, myalgias, fever, fatigue
or could be asymptomatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is cyclosporosis treated

A

antibiotics trimethoprim-sulfamethoxazole together called bactrim

sulf. . prevents growth of bacteria and
trimetho. .. is an antibiotic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the possible reactions to treatment for cyclosporosis

A

Stevens-Johnson syndrome-eruptions around mouth anus or eyes, disintegration of skin, liver damage, blood disorder, BM disorder
reactions to sulfonamide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where in the world is cyclosporosis found

A

common in tropics, subtropics, outbreaks reported in US and Canada

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Exlain the life cycle of cyclospora

A
  1. unsporulated oocysts are excreted in stool,
  2. environment is contaminated
  3. oocysts sporulate in environment
  4. sporulated oocysts enter food chain
  5. human ingests contaminated food/ water
  6. excystation in GI tract, asexual then sexual reproduction,
  7. unsporulated oocysts form, start over
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What illness does cyclospora cause

A

cyclosporosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What organism causes cyclosporosis

A

cyclospora

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

why is direct fecal-oral transmission not possible for cyclospora infection

A

because the oocyst is not infected at this stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What environment does a cyclospora oocyst need to sporulate

A

days or weeks, temp 22-32,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Explain sporulation in cyclospora life cycle

A

sporont divides into 2 sporocysts, which each have 2 elongate sporozoites. result is sporulated oocyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Explain excystation in cyclospora
oocyst excysts in GI tract of host, sporozoites are freed and invade epithelial cells of SI
26
What occurs in cells contaminated by cyclospora
schizogony-sexually mature into oocyst that shed in stool
27
How are cyclospora oocysts distinguished from cryptosporidium
mature oocysts have blue green fluorescence under UV light | cryptosporidium does not
28
What is different about isospora oocysts
each sporulated oocyst has 2 sporocysts
29
What kind of organism does isospora parasitize
mostly birds, sometimes mammals
30
Where in the world can isospora be found
all over, tropical and subtropical
31
What type of humans are often infected by isospora
immunodepressed and institutionalized groups
32
What symptoms does isosporosis have
acute nonbloody diarrhea, cramps in abs, lasts for weeks resulting in malabsorption and weight loss. severe in immunodepressed and children, eosinophilia
33
how is isoporosis treated
trimethoprim-sulfamethoxazole,
34
Describe the life cycle of isospora
1. oocyts released in feces, become immature oocysts with sporoblasts then sporocysts inside 2. mature oocysts with sporozoites are ingested 3. mature oocysts become sporozoites when excystation occurs 4. asexual reproduction creates merozoites 5. sexual reproduction results in oocysts released in feces, start over
35
Explain how isospora goes from an immatura oocyst to become sporozoites
immatura oocysts contains 1 sporoblast, sporoblast divides into 2 and secretes a cysts wall becoming a sporocyst, sporocyst divides twice producing 4 sporozoites
36
where and how does excystation occur in the isospora life cycle
in the SI , sporocysts excyst and release sporozoites which invade epithelial cells and start schizogony
37
Explain schizogony in isospora life cycle
schizonts rupture and release merozoites, invade epithelial cell, asexual reproduction
38
Map out stages of isospora, DRAW IT
OOCYST in feces-> meiosis, mitosis becomes INFECTIVE OOCYST->ingested becomes SPOROZOITE in SI->invades cell becomes TROPHOZOITE->becomes MERONT in enterocyte->merogony becomes MEROZOITE in lumen->can go back to troph/ MACRO and MICRO sexually reproduce becomes GAMETE-> fertilization becomes ZYGOTE->forms cyst wall becomes OOCYST.
39
Where are isospora trophozoites and what do they become
in invaded cell, become schizonts containing merozoites
40
What organisms do Eimeria infect
fowls-chickens, turkey
41
What organism is eimeria confused with
coccidiosis
42
why is eimeria significant
results in 7-9% of poultry industry loss
43
What conditions does eimeria live under
unsanitary, does well in summer
44
Why are fresh feces with eimeria non infective
sporogony from oocyst is exogenous
45
How long does sporogony in eimeria take
2 days in summer
46
what treatment is used to combat coccidiosis
no medication cures chicken once infected, prophylactic treatment is used-2 coccidiostat used in conjunction
47
Explain the life cycle of Eimeria
1. Sporozoite enters epithelial cell 2. Grows as trophozoite 3. Schizogony producing many merozoites 4. Schizont ruptures 5. Merozoites invade new epithelial cells 6.-10. Schizogony again, some merozoites loop here 11. & 15. 2nd and 3rd generation merozoites enter epithelial cells and take a different path (to 16 or 19). 16.-18. Many microgametes are produced & released 19.-20. Macrogametes are produced and stay in cell 21. Microgametes fertilize macrogametes in host epithelial cell and produce wall 22. Erupt from cell 23. These sporulate 24. Infective oocysts
48
What type of organisms does toxoplasma gondii infect
most warm blooded animals, definitive hosts are cats
49
How are cats infected with T gondii
ingesting oocysts from environment or from tissue of prey
50
what happens after a cat ingests a tissue cyst of T gondii
bradyzoites are released and move to SI epithelial cells and go through endodyogony
51
Explain endodyogony in T. gondii
2 daughters form in parent without nuclear conjugation, parent dissolves and 2 daughters form
52
How long does T gondii need to become infective
oocysts need 1-5 days to sporulate, can survive for months, resistant to drying and freezing.
53
How does T gondii go from a sporulated oocysts when ingested by a cat to a bradyzoite in a tissue
sporulated oocyst releases sporozoites and penetrates epithelial cells, sporozoites become tachyzoites and infect tissue, tachyzoites spread to other cells and become bradyzoites in a tissue cyst.
54
How can pregnant women avoid T gondii infection
no changing litter box, no uncooked meat, no mammal or bird meat
55
What are the infection rates of T gondii in humans, is it alarming?
16-40% of humans, cosmopolitan, few actual symptoms, only concerning with pregnancy
56
What are the symptoms of T gondii infection
swollen lymph nodes, muscle pain, fatigue, fever, sore throat, headaches.
57
What are the symptoms of congenital T gondii infection
causes congenital toxoplasmosis- tachyzoites cross placenta, later in life infants show vision loss, mental disability and seizures, retinochoroiditis-eye pain, light sensitivity, blurred vision, damage to retina
58
How severe is congenital toxoplasmosis
only possible during pregnancy, mother shows no signs, infection more severe during 1st than 2nd and 3rd trimester,
59
Congenital toxoplasmosis if early in pregnancy there is __ transmission but __ pathology. If late in pregnancy there is __ transmission but ___ pathology
low, high | high, low
60
How does toxoplasmosis affect the immunocompromised
worse symptoms, at risk of relapse, HIV+ more likely to develop severe infection
61
What organisms does Neospora caninum infect, which is the definitive host
dogs (definitive) and cattle, can cause neosporosis
62
What are the symptoms of neosporosis
continuous abortion in cattle, in puppies- 7 weeks old muscle atrophy, heart failure, jaw and hind leg paralysis
63
explain the life cycle of neospora caninum
oocysts excreted in dog feces, sporulate in environment, cattle graze and ingest it, in infected meat bradyzoites are in tissue cysts can cross placenta, passed in feces

Parasitology (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions