Medical Parasitology

Question 1

What are Protozoa

Answer 1

Single-celled organisms with a nucleus which are non-photosynthetic

Question 2

What’s a ‘direct’ life cycle?

Answer 2

One where a parasites life cycle requires only one host

Question 3

What’s an ‘indirect’ life cycle?

Answer 3

One where a parasite requires two or more hosts to complete its life cycle

Question 4

‘Direct transmission’?

Answer 4

Direct physical means of transmission, eg contaminated faecal material

Question 5

Transmission via an intermediate host or vector?

Answer 5

Mechanical with one or more life cycle stages taking place. The sexual stage takes place in the ‘definitive host’

Question 6

Zoonosis

Answer 6

Any disease transmitted from humans to animals, who form ‘reservoir hosts’ eg African sleeping sickness

Question 7

Anthroponosis

Answer 7

A disease spread from humans to humans eg smallpox, malaria

Question 8

Trophozoite

Answer 8

Feeding growing and dividing stage of a protozoan

Question 9

Cyst

Answer 9

1. A walled off cavity containing multiple organisms often important in transmission eg trichinella, toxoplasmosis
2. A microscopic resistant form shed into the environment for transmission eg Entamoeba

Question 10

What Protozoa are particularly dangerous to the immunocompromised?

Answer 10

Toxoplamsa gondii

Cryptosporidium

Question 11

What fungi are particularly dangerous to the immunocompromised?

Answer 11

PCP Pneumocystis Jirovecii

Microsporidiosis : encephalitozoon intestinalis

Question 12

Definition:
pathogen
Commensal
Symbionts

Answer 12

Causes harm
Harmless
Beneficial

Question 13

What’s Burkett’s lymphoma

Answer 13

Epstein-Barr virus with malaria falciparum co-infection causing lymphoma