Introduction to Parasites

Question 1

Define: Parasite

Answer 1

An organism that:
> Lives in/on a host
> Derives benefit
> Causes host injury

Question 2

Define: Symbiosis

Answer 2

> Living together
Long term
Between two diff species

Question 3

Define: Mutualism

Answer 3

Where both species benefit

Question 4

Define: Commensalism

Answer 4

Where parasite benefits to no host injury.

Question 5

Define: Definitive Host

Answer 5

Harbours adult parasite or reproducing parasite.

Question 6

Define: Intermediate Host

Answer 6

Harbours larval or asexual parasite.

Question 7

Define: Paratenic Host

Answer 7

Harbours non-developing parasite.

Question 8

What can Parasites be classed into?

Answer 8

Protozoa or Helminths

Question 9

What is the name for macro-parasites?

Answer 9

Helminths

Question 10

What is the name for micro-parasites?

Answer 10

Protozoa

Question 11

Protozoa can be divided into what 4 categories?

Answer 11

> Flagellates
Amoeboids
Sporozoa
Trypanosomes

Question 12

Helminths can be divided into what 2 categories?

Answer 12

> Platyhelminths (flatworms)

> Nematodes (round worm) - Intestinal/Tissue

Question 13

Platyhelminths (flatworms) can be divided into what 2 sub-categories?

Answer 13

> Cestodes (Tapeworm)

> Trematodes (Flukes)

Question 14

What type of Protozoa is Guardia Lamblia?

Answer 14

Flagellate

Question 15

What type of Protozoa is Toxoplasma?

Answer 15

Sporozoa

Question 16

What type of Protozoa is Leishmania?

Answer 16

Trypanosome

Question 17

What is a direct life cycle?

Answer 17

Only affects one species

Question 18

What is an indirect life cycle?

Answer 18

More than one species, with a intermediate host.

Question 19

What is a complex indirect life cycle?

Answer 19

More than one species, intermediate host and paratenic host.

Question 20

What is Ascariasis?

Answer 20

A helminth- intestinal nematode. Caused by Ascaris Lumbricoides.

Question 21

How much of the world pop is infected with Ascariasis?

Answer 21

1/7th world pop.

Question 22

What is the prevalence of Ascariasis?

Answer 22

3-8 year olds.

Question 23

What is the life cycle of Ascariasis?

Answer 23

Direct

Question 24

What lung condition can Ascariasis cause?

Answer 24

Loeffler’s Syndrome

Question 25

What are the symptoms of Loeffler's syndrome (caused by Ascariasis)?

Answer 25

``` > Dry Cough > Wheeze > Haemoptysis > Dyspnoea > Eosinophilic pneumonitis ```

Question 26

What are Albendazole and Benzimidazole used to treat?

Answer 26

Ascariasis

Question 27

How do Albendazole and Benzimidazole work?

Answer 27

Prevent worm glucose absorption - starve it.

Question 28

What is Schistosomiasis?

Answer 28

A fluke (type of helminth)

Question 29

What disease results from Schistosomiasis infection?

Answer 29

Bilharzia.

Question 30

What does Bilharzia disease cause?

Answer 30

Bladder cancer and liver disease.

Question 31

What is the life cycle of Schistosomiasis?

Answer 31

Indirect

Question 32

What is the intermediate host of schistosomiasis?

Answer 32

Snails.

Question 33

What is the rash caused by Schistosomiasis?

Answer 33

Swimmer's Itch

Question 34

What is another word for Acute Schistosomiasis?

Answer 34

Katayama Fever

Question 35

What is the Schistosomiasis form that causes urinary problem?

Answer 35

S.Haemotobium

Question 36

What symptoms does S.Haemotobium cause? | Hint : Urinary

Answer 36

> Bladder Squamous cell carcinoma. > Haematuria > Bladder fibrosis/dysfunction

Question 37

What effect does Schistosomiasis have on hepatic/intestinal?

Answer 37

> Portal hypertension | > Liver Cirrhosis

Question 38

What is Praziquantel used to treat?

Answer 38

Schistosomiasis

Question 39

How does Praziquantel work?

Answer 39

Increase ion permeability --> tetanic contraction --> detachment --> death.

Question 40

What type of parasite causes Hyatid Disease?

Answer 40

Helminth --> Platyhelminth --> Cestode (Tapeworm)

Question 41

What is the parasite that causes Hyatid Disease?

Answer 41

Echinococcus Sp.

Question 42

What Echnicoccus causes cystic hyatid disease?

Answer 42

E. granulosus

Question 43

What Echinococcus causes alveolar hyatid disease?

Answer 43

E. multicilocularis

Question 44

What percentage of Hyatid cysts are in the lungs?

Answer 44

20%

Question 45

What percentage of Hyatid cysts are in the liver?

Answer 45

70%

Question 46

What are symptoms of Hyatid disease?

Answer 46

May be asymptomatic

Question 47

What can Hyatid disease also cause?

Answer 47

Secondary bacterial infection

Question 48

What does cyst rupture cause?

Answer 48

Hypersensitivity

Question 49

What is Malaria caused by?

Answer 49

> P. Malariae > P. Falciparum > P. Oval > P. Vivax

Question 50

What type of parasite is Malaria?

Answer 50

Protozoa - Sporozoan

Question 51

What does Malaria do to RBC?

Answer 51

Cause them to rupture every 48-72 hrs.

Question 52

What symptoms does burst RBC cause?

Answer 52

Fevers and Rigors. | Anaemia, bleeding & DIC.

Question 53

What symptoms do Cerebral Malaria cause?

Answer 53

Confusion, Headache and coma.

Question 54

Why does Malaria cause renal failure?

Answer 54

Hb into urine - RBC burst.

Question 55

What causes Cryptosporidiosis?

Answer 55

Cryptosporidium parvum and hominis

Question 56

What type of parasite is Cryptosporidium parvum/hominis?

Answer 56

Protozoa --> Sporozoa

Question 57

What are the symptoms of Cryptosporidiosis? | Hint: Think GI

Answer 57

Watery diarrhoea w/ mucus (no blood). | - Bloating, cramps, nausea, vomiting

Question 58

How long does Cryptosporidiosis incubate for?

Answer 58

2-10 days (usually 7)

Question 59

How is Cryptosporidiosis spread?

Answer 59

> Human-human | > Animal-human

Question 60

In whom is Cryptosporidiosis severe?

Answer 60

> Very old/young | > Immunocompromised

Question 61

What does symptomatic treatment of Cryptosporidiosis involve?

Answer 61

> Rehydration | > Nitazoxanide

Question 62

What does immunocompromised treatment of Cryptosporidiosis involve?

Answer 62

> Nitazoxanide > Paromomycin - kill parasite. > Octreotide (reduce cramps and frequency)