Introduction to Parasitology

Question 1

What is a parasite?

Answer 1

• a parasite is an organism that lives in another organism (host) and gets its food at the expense of this host
• simple organisms
• more complex than bacteria

Question 2

What is the outcome is of parasitical infections?

Answer 2

• tremendous burden of disease in both the tropics and subtropics as well as in more temperate climates

Question 3

Which parasites causes the most deaths globally?

Answer 3

• malaria

Question 4

What are the thee classes of parasites?

Answer 4

• protozoa
• helminths (worms)
• arthropods

Question 5

What is a protozoa?

Answer 5

• microscopic, one-celled organisms
• can be free-living or parasitical in nature
• able to multiply in humans

Question 6

How are protozoa transmitted?

Answer 6

• fecal-oral route (protozoa that live in a human’s intestine)
• arthropod vector (protozoa that live in the blood or tissue of humans)

Question 7

What is malaria?

Answer 7

• a protozoan infection
• mosquito-borne disease caused by a parasite
• patient often experience fever, chills, and flu-like illness
• left untreated, severe complications and die

Question 8

What organism causes malaria?

Answer 8

• plasmodium falciparum

Question 9

What is the mosquito vector?

Answer 9

• anopheles mosquito

Question 10

How to detect malaria?

Answer 10

• giemsa stained blood film shows infected red cells (parasitaemia)
• thick and thin blood films

Question 11

What is malaria’s life cycle?

Answer 11

• sporozoites injected under skin by mosquito
• travel through blood and enter liver
• mature in liver and re-enter circulation as merozoites
• invade red cells, multiply and lyse cells- reinvade more red cells
• sexual forms taken up by mosquito

Question 12

How do you control malaria?

Answer 12

• insecticide treated mosquito nets
• prophylaxis
• malaria vaccine research