Introduction to Parasites 2

Question 1

What are the three classes of parasites?

Answer 1

Protozoa, helminths and arthropods

Question 2

Describe the structure of protozoa

Answer 2

Single celled organisms

Question 3

What is the mode of protozoa transmission?

Answer 3

Intestinal parasites - fecal - oral routeBlood parasites - arthropod vector

Question 4

What is the species responsible for malaria?

Answer 4

Plasmodium falciparum

Question 5

What is the vector for malaria?

Answer 5

Anopheles mosquito

Question 6

What is the life cycle of malaria?

Answer 6

Sporozoites are injected under the skin by the mosquito, they travel through blood and enter the liver, they mature in the liver and re-enter the circulation as merozoites. Merozoites invade red cells, multiply and lyse cells

Question 7

What is the diagnosis of amoebic dysentery?

Answer 7

Cysts in formed stool - microscopyDiarrhoea with blood and pus

Question 8

What type of disease is Amoebic Dysentery responsible for?

Answer 8

Intestinal and extra-intestinal infectionsLiver abscess in late disease

Question 9

What infection is caused by the bite of sandflies?

Answer 9

Leishmaniasis

Question 10

What is cutaneous or muco-cutaneous leishmaniasis characterised by?

Answer 10

Skin or mucosal ulceration

Question 11

What is Viceral leishmaniasis caused by?

Answer 11

Fever weight loss and hepato-splenomegaly

Question 12

How is diagnosis of leishmaniasis achieved?

Answer 12

Histology of biopsy material

Question 13

What are the different types of helminths?

Answer 13

Nematodes, Cestodes, Trematodes

Question 14

What are Nematodes?

Answer 14

Round worms

Question 15

What are Cestodes

Answer 15

Tapeworms

Question 16

What are trematodes

Answer 16

Flatworms

Question 17

What is the diagnosis of nematodes?

Answer 17

Press adhesive sellotape against perianal region

Question 18

What is the lifecycle of Ascaris lumbricoides - nematode?

Answer 18

Ingested eggs hatch in the intestine, larvae carried by circulation to the lungs, swallowed again, adult worms develop in and inhabit small intestine

Question 19

What are the various methods of ingesting a tapeworm?

Answer 19

Larval cysts ingested in meat, ingest eggs in dog faeces

Question 20

Where is there a high incidence of Schistosomiasis

Answer 20

Near fresh water, snail is important in the life cycle intermediate host

Question 21

What accompanies a helminth infection?

Answer 21

EosinophiliaElevated IgE

Question 22

How is diagnosis of a parasite infection achieved?

Answer 22

Microscopy of parasites cysts and ovaSerology - detection of antibodies Blood films for malaria

Question 23

Are cultures of parasites possible?

Answer 23

rarely

Question 24

Schistosomiasis is what kind of parasite?

Answer 24

Flatworm (trematode)

Question 25

Ascarius lumbricoides is what kind of parasite?

Answer 25

Round worm (nematode)

Question 26

What kind of parasite infection is leishmaniasis and amoebic dysentry?

Answer 26

Protozoal