Cryptosporidium Flashcards Preview

Parasitology > Cryptosporidium > Flashcards

Flashcards in Cryptosporidium Deck (25):
1

What are the three types of emerging diseases?

not occurred in humans before, previously occurred but only in small numbers, and occurred throughout history but recently recognised as a distinct disease

2

What is a re-emerging disease?

a disease that was once a major health problem, then declined dramatically, and again is becoming a major health issue

3

To which phylum does Cryptosporidium belong?

Apicomplexa (all parasites in this phylum are called coccidia)

4

Where does Cryptosporidium develop in the body?

In the GI tract

5

Why is Cryptosporidium an unusual Apicomplexan?

it is phylogenetically very distant to other species in the phylum

6

What is the infective stage?

oocysts

7

Which are the two most important organelles in the apical complex?

micronemes and rhoptry

8

How is the oocyst unique?

the oocyst wall has a suture at the end that dissolves during excystation. this allows the sporozoites to colonise the villi of the small intestine

9

How are oocysts transmitted?

Through the fecal-oral route

10

Is C. parvum species specific?

no

11

What is the most common clinical symptom?

diarrhea

12

What are some other clinical symptoms?

abdominal pain, nausea, fever, fatigue, breathing

13

Which group of individuals shows less signs of symptoms?

immunodeficient individuals

14

Which group of individuals has the highest mortality rate?

persons with AIDS

15

What effect do the metabolites secreted by Cryptosporidium have on the body?

-inhibition of glucose-stimulation affecting Na absorption
-increased production of mucosal prostaglandin which can inhibit NaCl absorption (leading to diarrhea)

16

What affect does the immune system reacting to Cryptosporidium have on the body?

-leukocytes can produce high levels of prostaglandins
-alterations in intestinal permeability via increased secretions of cytokines (ex. IFN-gamma and TGF)

17

How can one contract the parasite?

from animals, manure used as fertilizer, person-to-person contact, waterborne, foodborne, airborne

18

Who is at risk?

veterinarians, farmers, medical personel, day-care workers, immunodeficient people, children, owning pets, family, sexual activities (anaallll), non-filtered water, etc

19

What is the percent efficiency of using water samples to test for the presence of Cryptosporidium?

6.3%

20

What are some new detection methods and what are the disadvantages?

ELISA and PCR
both are expensive, cannot distinguish between viable and non-viable cells, and they are not species-specific

21

What is apparently the best water treatment method?

sand filtered water

22

What is the percent of surface water that was tested positive in Canada and in Quebec?

4.5% in Canada, 12% in Quebec only

23

What is the issue with chemotherapy and this disease?

because chemo destroys the host immune system, they cannot fight the infection on their own and must take drugs

24

Which drugs have been used successfully to treat cryptosporidiosis?

spiramycin, azithromycin, paromomycin

25

How invasive is the parasite?

not very invasive. only resides on the apical surface of intestinal epithelium. still elicits innate and acquired immune responses and causes inflammation