Introduction to Parasites

Question 1

What is a parasite

Answer 1

an organism that lives in another organism (host) and gets its food at the expense of the host

Question 2

Protozoa

Answer 2

Coccidia (Malaria)
Amoebae
Flagellates
Cilates
Microsporidia

Question 3

Helminths (worms)

Answer 3

Roundworms
Tapeworms
Flatworms

Question 4

Arthropods

Answer 4

Lice
Ticks
Mites

Question 5

Plasmodium species of malaria

Answer 5

P. falciparum

Question 6

Symptoms of malaria

Answer 6

fever, chills and flu-like symptoms

Question 7

Vector for malaria

Answer 7

Mosquito (Anopheles)

Question 8

Stages of infection in malaria

Answer 8

1. Spoirozoites injected under skin
2. travel through blood to liver
3. Mature and enter circulation as merozoites
4. Invade red cells, multiply and lyse and reinvade more cells
5. Gametocytes are taken up mosquitos

Question 9

Thin Blood Smear

Answer 9

Fixed in methanol and allows identification of species and quantification

Question 10

Thick Blood Smear

Answer 10

Increased sensitivity but limited parasite morphology. Not fixed in methanol

Question 11

Malaria control

Answer 11

Insecticide, mosquito nets, prophylaxis

Question 12

Amoebic Dysentry

Answer 12

Diarrhoea with blood

Question 13

Trophozoites ingest red cells by throwing out pseudopodia

Answer 13

Entamoeba histolytica

Question 14

Detection of amoebea infection

Answer 14

Microscopy of cysts found in stools

Question 15

Leishmaniasis species

Answer 15

Flagellate

Question 16

What does it cause and Where is Leishmaniasis found

Answer 16

Skin or mucosal ulceration. Can be cutaneous or muco-cutaneous

Question 17

Cause of Leishmaniasis infections

Answer 17

Sandflies- black fever

Question 18

Nematodes

Answer 18

Round worms

Question 19

Cestodes

Answer 19

Tape worm

Question 20

Trematodes

Answer 20

Flat worms

Question 21

Nematodes Species and Features

Answer 21

Enterobius (pin worm)- found in children

Ascaris lumbricodes- Loeffler’s syndrome- respiratory illness caused by accumulation of eosinophils

Question 22

Cestodes Species and Features

Answer 22

Taenia saginata- beef
Taenia solium - pork and causes Cysticercosis through ingestion of eggs
Echinococcus- carried by animals and form hyatid cysts in liver

Question 23

Trematodes Species and Features

Answer 23

Schistosomiasis 
S. haematobium (bladder)
S. mansoni (intestinal)
S. japomicum (intestinal)
penetrate body of snail --> Carcaria emerge from snails --> penetrate human skin---Lungs to liver- lay eggs in bladder and mesentry = Katayma fever

Question 24

Katyama Fever

Answer 24

Schistosomiasis (Flat worm)

Question 25

Carcaria emerge from snails

Answer 25

Schistosomiasis (Flat worm)

Question 26

S. haematobium (bladder)
S. mansoni (intestinal)
S. japomicum (intestinal)

Answer 26

Schistosomiasis (Flat worm)

Question 27

Elevated eosinophilia and elevated levels of IgE

Answer 27

Helminth infection (worm)

Question 28

Diagnosis of parasite infection

Answer 28

Microscopy
Blood films
Serology