Toxoplasma Flashcards
What is special about Toxoplasma and felines?
Toxoplasma can only undergo sexual reproduction in felines (only asexual in every other species)
Prevalence of Toxoplasma?
high, it’s everywhere, infects ~1/3 of human population and also present in dogs, cats, pigs, sheep, and more
Toxoplasma is a leading cause of abortion in what two species?
sheep and goats
Toxoplasma gondii sources of infection
cat feces, contaminated water/veggies, raw or undercooked meat
How do cats pick up toxo?
hunting birds and rodents (ingesting sporulated cysts)
Where in the cat does toxo undergo sexual reproduction?
enterocytes
Asexual Reproduction of Toxoplasma
oocysts rupture, transform into tachyzoites, these multiply in ANY nucleated cell in the body, will encyst to avoid the immune system and these cysts can be found in CNS, muscles, and visceral tissue
Why is the cat the best host for Toxoplasma gondii?
cats have a lot of linoleic acid (a fatty acid) because, surprise surprise, they lack the enzyme required to break it down
Three Forms of Toxoplasma
- Oocyst
- Tachyzoites
- Bradyzoites/Cysts
Which form of toxoplasma is infectious?
trick question, they all are
only non infectious when it’s a non-sporulated oocyst in the environment
endodyogeny
a form of asexual reproduction, forms two daughter cells within the mother cell
“toxo”
bow
apicoblast
a plant-like organelle which makes a good drug target
Are bradyzoites indicative of acute or chronic infection?
chronic
What species are asymptomatic when infected with Toxoplasma?
horses, cattle, chicken (and most cats) (and some humans)
Ocular Toxoplasma
result of congenital infection
severe retinochorditis and can get keratic precipitates in the cornea
