Lecture 3A - Parasites and Viruses Flashcards

1
Q

What forms can parasites adopt?

A

ectoparasits e.g. fleas, head lice

endoparasites - worms

singe cell - protozoa e.g. plasmodium species

viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are endoparasites?

A

large multicellular parasites like worms

can invade and multiply inside the body and take up residence in tissue spaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are protozoa?

A

single celled organisms, which can spend part of their life cycle reproducing inside cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do viruses and prions need to reproduce?

A

the assistance of the intracellular metabolic machinery of the host organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cysticercosis?

A

1000 hospitilsations/year
Taenia solium tapeworm

makes it’s home in human tissue such as brain and muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where are larval cysts of taenia solium found?

A

in uncooked pork

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Chagas disease?

A

300,00 infections

leads to long term digestive, cardiac and neurological complications if not treated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What causes chagas disease?

A

trypanosoma cruzi (T.cruzi)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Trichomoniasis?

A

STD (3.7 million infected)

only 30% have symptoms of itching and burning with urination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What causes trichomoniasis?

A

protozoan - trichomonas vaginalis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Toxocara?

A

caused by larvae of roundworm found in guts of dogs and cats

can cause eye disease/blindness especially in children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What causes toxocara?

A

Toxocara canis or T. cati

50 million have antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Toxoplasma gondii?

A

protozoan

from cat faeces

causes swollen lymph nodes, muscle aches and eye complications - can become chronic if not treated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are ectoparasites?

A

live on the surface of a host but need some product from(nutrient or genetic material) in order to survive (often a blood meal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What can ectoparasites do when taking a blood meal?

A

inject viruses, protozoans and bacteria along with some form of anti-coagulant into the human subject

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do endoparasites live?

A

inside the body

17
Q

Examples of ectoparasites?

A

head lice

ticks (vectors for chagas disease, lyme disease)

mites

fleas

18
Q

Headlice?

A

pediculus humanus capitis

wingless insects very common in school children aged 4-11

19
Q

How is head lice transferred?

A

by head to head contact

20
Q

How do head lice attach to the host?

A

the female cements pinhead sized eggs to hairs near to the root where the scalp keeps them warm

21
Q

How long does it take head lice to hatch?

A

around 9 days (white nit stage), but they initially remain attached to the hair, later they begin feeding

22
Q

How do head lice feed?

A

by biting the scalp and drawing blood

in another 9-10 days they are fully mature and the females are able to lay more eggs

23
Q

How can head lice be treated?

A

by combing (0.2-0.2mm comb) or lotions

24
Q

Body lice?

A

pediculosis corpis

25
Pubic lice?
phthirus pubis
26
Where do body/pubic lice live?
they live and feed on specific skin regions
27
What are mites?
arachnids
28
Sarcoptes scabei?
mite that causes scabies - female burrows into the skin and lays eggs
29
Dermatophagoides pteronyssinus?
dust mite lives off dead skin and causes dermatitis and asthma
30
Ticks?
also arachnids live on the skin and feed off blood
31
What do ticks act as?
vectors for many serious illnesses in humans and animals
32
Fleas?
wingless insects with an extraordinary ability to jump eggs may hatch in carpets for more than a week before the flea hatches and jumps onto the skin of the host for a blood meal
33
What can lice transmit?
typhus can be transmitted in clothing or reside there between baths
34
What can ticks transmit?
chagas disease and lyme disease
35
Size of fleas?
1.5 to 3mm long, but can jump vertically 18cm and horizontally 33cm