Toxoplasma gondii

Question 1

order

Answer 1

eucoccindiorida- parasite of epithelial cells

Question 2

hosts

Answer 2

cats and other felids

Question 3

intermediate hosts

Answer 3

humans, dogs, livestock, or birds

Question 4

is there zoonosis?

Answer 4

yes

Question 5

size

Answer 5

12 micrometers

Question 6

what does the oocysts contain once sporulated?

Answer 6

2 sporocysts each with 4 sporozoites

Question 7

life cycle

Answer 7

unsporulated oocysts are shed in cats feces
oocysts form into tachyzoites- rapidly multiply
intermediate host ingest tachyzoites and they localize in muscle tissue and become bradyzoites
cat eats the tissues of the intermediate host with cysts
tissue cysts wall is digested in cats stomach
liberated bradyzoites initiate schizogonous and gametogenous development resulting in production of oocysts

also, organs invade extraintestinal tissues where tachyzoites and bradyzoites proceed as in intermediate host

Question 8

how long do oocysts take to sporulate?

Answer 8

1-5 days

Question 9

how do intermediate hosts become infected?

Answer 9

ingesting soil contaminated with oocysts

Question 10

how do cats become infected

Answer 10

eat the intermediate host harboring tissue cysts or by directly ingesting the sporulated oocysts

Question 11

_____ may also become infected with tissue cysts after ingestion of sporulated oocysts

Answer 11

wild game- liberated sporozoites spread via blood. tissue cysts form containing bradyzoites

Question 12

what is the invasive and proliferative stage?

Answer 12

tachyzoite

Question 13

how can humans become infected?

Answer 13

foodborne- eating raw infected meat
animal to human- ex. cat litter
mother to baby- transplacental

Question 14

what happens in the human host?

Answer 14

parasites form tissue cysts

these cysts remain there throughout the life of the host

Question 15

how are humans diagnosed?

Answer 15

serology or biopsy specimen

Question 16

site of infection

Answer 16

intestinal and extratintestinal tissues

Question 17

pathogenesis

Answer 17

most animals asymptomatic - depends on organs involved
death of intestinal cells
acute toxoplasmosis- severe with FIV
pneumonia

Question 18

diagnosis

Answer 18

serological test

ELISA or IFA tests

Question 19

cats develop ____ after initial infection and shed only ___ in a lifetime

Answer 19

immunity, once

Question 20

how often are oocysts usually shed in cat feces?

Answer 20

1-2 week period

Question 21

treatment

Answer 21

humans avoid feces and eating uncooked meat
no vaccine approved
Nonsulfonamides and sulfonamides

Question 22

serious concern of exposure of human ___ to hazard of death

Answer 22

fetuses

Question 23

what is toxoplasmosis?

Answer 23

transplacental transmission- many side effects to fetus

Question 24

toxoplasmosis can effect either a ____ host or a ____ host

Answer 24

nonimmune, immune