Parasitic Diseases- Protozoa Flashcards
what are the 4 classifications of protozoa?
- mastigophora: flagellates
- sarcodina: amoebae
- ciliophora: ciliates
- apicomplexa: apicomplexans
describe mastigophora
have a long flagella for movement
describe sarcodina (3)
only a few parasites in this class, water-borne and cause neurologic symptoms
describe ciliophora, give a special case
have cilia for movement, rumen protozoa are ciliates, but NOT parasites, symbiotic
describe apicomplexa
angular vertex structure to help parasite burrow into cells and tissue
give 2 common charaterisitics of all protozoans
- unicellular
2. have 2 life cycle phases: cyst/oocyst and trophozoite
describe the cyst/oocyst life cycle phase of protozoans (3)
- resistance phase to protect from dehydration/in the environment
- infective to new hosts
- covered by a protecting wall
describe the trophozoite phase of protozoans
- vegetative form, inside the host
- parasite replicates by sexual or asexual methods and feeds on the host
- has the ability to move around in host body
describe the typical fecal-oral life cycle of protozoans in terms of cyst/oocyst and trophozite
- cysts are passed in feces, resistant, and infective
- once in new host, excystation occurs and now the trophozoite is feeding, motile, and replicating
- trophozoite undergoes encystment and is passed in feces as cycle starts again
what classification of protozoan is Giardia spp.?
a flegellate
where is the protozoan Giardia spp. found?
in the small intestine of a wide range of mammalian hosts
where does Giardia spp. attach in the host? why can this be a problem for the protozoan?
to the ventral surface on intestinal lining; the epithelial cells lining intestinal villi are continually being shed so the Giardia trophozoites have to relocate frequently
when attached to the intestinal lining, what do Giardia trophozoites do? (2)
- asexual mitosis to replicate
2. mainly cause diarrhea and steatorrhea (yellow, fatty feces) due to eating the intestinal lining
what does a heavy infection of Giardia spp. do to the host?
flattens intestinal mucosa, which causes decreased production of digestive enzymes, malabsorption, of nutrients, and weight loss
what type of life cycle does Giardia spp. have?
direct life cycle
describe the direct life cycle of Giardia spp.
trophozoites live in the villi of the small intestine, where they undergo encystation, then the cysts pass in feces, where they are ingested by the host and undergo excystation to become trophozoites in the villi again
what is the one health concern for Giardia spp.? how avoid?
zoonotic!! wash your vegetables (if fertilized with manure) and treat your water!
how do you diagnose Giardia spp.?
find cysts in feces
how do you treat Giardia spp.?
kind of back door, there’s no approved drugs for treatment in dogs and cats in the USA… but antihelmintics work pretty well
how do you control the spread of Giardia spp.? (3)
isolate infected individuals, bathe them to remove cysts, and remove feces from areas and animals to limit ingestion spread
what classification of protozoans are coccidia?
apicomplexans
what are the 2 types of coccidia?
- eimeria
2. isospora
what mess-you-up things do coccidia do and how?
acute invasion and destruction of intestinal mucosa, can get inside cells (intracellular parasites!)
what symptoms do coccidia cause?
the general, nonspecific symptoms most often seen in increased stress such as diarrhea, fever, loss of appetite, weight loss, death in extreme cases
in what 6 animals is coccidiosis and economically important disease?
- cattle
- sheep
- goats
- pigs
- poultry
- rabbits
in what 3 animals is coccidiosis less common?
- dogs
- cats
- horses
in an eimeria oocyst, or egg, how many sporocysts are there and how many sporozoites are there in those?
4 sporocysts, each with 2 sporozoites, so each oocyst can make 8 trophozite protozoans
in an iospora oocyst, or egg, how many sporocysts are there and how many sporozoites are inside that?
2 sporocyst each with 4 sporozoites, so each oocyst can also make 8 trophozoite protozoans
describe the amount of species of coccidia
multiple species with specific hosts
what kind of life cycle do coccidia have?
direct, only one host