parasitology

Question 1

what are parasites

Answer 1

eukaryotes; chronic and prolonged course of infection; most of them have complex life cycles; exogenous to the human host

Question 2

types of parasites

Answer 2

protozoa (unicellular: plasmodium sp.)
helminths (worms: tenia sp.)
exoparasites (arthorpods: lice)

Question 3

cause and spread of malaria

Answer 3

protozoa: plasmodium falciparum, p. vivax, p. malariae, p. ovale

spread by the anopheles mosquito; definitive host; sexual cycle

Question 4

developmental life stages of plasmodium spp.

Answer 4

mosquito stages; human liver stages; human blood stages

Question 5

malaria symptoms

Answer 5

chills, fever, vomiting, headache

Question 6

malaria etiology

Answer 6

mosquito bite introduces the protozoa into the host’s blood stream, protozoa infect and lyse red blood cells; causes anemia; lysed RBCs block blood vessels, leads to tissue death

Question 7

trichomonas vaginalis

Answer 7

trichomonias; protozoa; sexually transmitted

Question 8

trichnomoniasis

Answer 8

disease most common in women

symptoms: in men (rare) - burning after urination, mild discharge
in women - greenish-yellow discharge with a strong odor, itching, painful urination

Question 9

toxoplasma gondii

Answer 9

protozoa; cats are the definitive host; sexual cycle of the parasite occurs in the cat

Question 10

transmission of toxoplasma gondii

Answer 10

transmission occurs to humans; water and food contaminated with oocysts; changing cat litter box; eating undercooked meat of animals with tissue cysts; transplacentally; blood transfusions and organ transplants

Question 11

toxplasmosis infection

Answer 11

in healthy people is mild
in immunocompromised patients: more dangerous
the primary dange is congenital infection (transplacental): stillbirth, child is born with brain damage/visual problems

Question 12

water-born parasite species

Answer 12

protozoa - entamoeba histolytica; cryptosporidium sppp. giardia lambia

Question 13

transmission of water-borne parasites

Answer 13

drinking water contaminated with animal wastes; swimming pools; resistant to chlorination

Question 14

2 types of amebiasis

Answer 14

intestinal - cysts pass through the stomach where the exposure to gastric acid stimulates the release of the pathogenic trophozoits in the duodenum; the trophozoites cause necrosis in the large intestine

extraintestinal - mainly in the liver

Question 15

cryptosporidium spp.

Answer 15

cryptosporidosis

Question 16

cryptosporidosis

Answer 16

protozoa (c. hominis, c. parvum)

invade the epithelial cells of the intestines causing watery diarrhea, stomach pains, cramps and fever

Question 17

giardia duodenalis

Answer 17

giardiasis

Question 18

giardiasis

Answer 18

protozoa (giardia lamblia); flagetllate; attaches to the intestinal villi with an adhesive disk, resulting in localized tissue damage