26. Arthropods (lice, part 1) Flashcards

1
Q

where can lice be found?

A

on people’s heads, and human bodies, including the pubic areas

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

how do human lice survive?

A

by feeding on human blood

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

what do both males and females (immature and adult) require to complete their development?

A

blood meals

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

which is the only louse known to spread disease?

A

body louse

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

how are lice infections spread most commonly?

A

by close person to person contact

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

do cats, dogs and other pets play a role in transmission of human lice?

A

no

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

how do lice move?

A

by crawling

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

can lice fly or jump?

A

no

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

do lice have wings?

A

no

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

what do lice have on their legs? what are they for?

A

claws that grip and hold onto their shafts

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

how many legs do lice have?

A

6 legs

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

how many segments do the antennae have?

A

5 segments

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

what is the shape of their abdomens?

A

longer than they are wide

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

are the lice found in different parts of the body the same?

A

no, they are different from each other

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

what are the three types of lice found on humans?

A
  • Pediculus humanus capitis (head louse)
  • Pediculus humanus corporis (body louse, clothes louse)
  • Pthirus pubis (“crab” louse, pubic louse)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the head louse?

A

Pediculus humanus capitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the body louse, clothes louse?

A

Pediculus humanus corporis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the “crab” louse or pubic louse?

A

Pthirus pubis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

among who, is head lice most common?

A

among preschool and elementary school-aged children and their household members and caretakers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

are head lice known to transmit disease?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is a common malignancy associated with head lice?

A

secondary bacterial infections of the skin resulting from scratching (any lice infestation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

is getting head lice related to cleanliness?

23
Q

what is the most common way to get head lice?

A

head to head contact with an already-infected person

24
Q

what is head lice’s means of camouflage?

A

they can change their color to match the hair of the infected person

25
how are lice treated?
with lice-killing shampoos and rinses (insecticides), and nit combs should be used to comb nits and lice from the hair shaft
26
what are nits?
lice eggs, laid by the adult female at the base of the hair shaft nearest the scalp
27
how long to nits take to hatch?
1 week
28
what does the nit hatch into?
nymphs
29
what does the lice nymph resemble?
they look like adult head louse, but is the size of a pinhead
30
after how many molts are nymphs mature?
3 molts
31
how many days after hatching are lice nymphs are eventually adults?
about 7 days
32
how many legs do adult lice have? how many claws?
6 legs, each having a claw
33
what color is adult lice?
tan to greyish white
34
who is larger in lice, females or males?
females are usually larger than males
35
how many nits do female lice lay per day?
up to 8
36
how long can lice live on a person's body?
up to 30 days
37
where do body lice live that is different from other lice?
body lice prefer to live in the seams and linings of unwashed clothing, blanket and sheets and only move to the skin to feed
38
how long without blood meals can body lice go before they die?
1 to 2 days
39
where are the nits of body lice found?
Although body lice usually deposit their nits on unwashed clothing fibers, the nits are sometimes found on body hair as well
40
are body lice known to spread disease?
yes
41
what can body lice spread in terms of diseases?
epidemic typhus trench fever louse-borne relapsing fever
42
is louse-borne epidemic typhus wide spread?
no
43
do outbreaks of louse-borne epidemic typhus still occur? if yes, when?
yes, in times of war, civil unrest, natural or man-made disasters, and in prisons where people live together in unsanitary conditions
44
where does Louse-borne typhus still exist?
in places where climate, chronic poverty, and social customs or war and social upheaval prevent regular changes and laundering of clothing
45
how us body lice infestation diagnosed?
by finding eggs and crawling lice in the seems of clothing or feeding on skin
46
how is a body louse infestation treated?
by improving the personal hygiene of the infected person, including assuring a regular (at least weekly) change of clean clothes
47
how do you treat the environment of an infected person?
Clothing, bedding, and towels used by the infested person should be laundered using hot water (at least 55°C) and machine dried using the hot cycle
48
where can pubic lice be found?
- usually attached to pubic hair - can also be found in the eyebrows, eyelashes, beard, moustache, chest, armpits, etc - any course hair
49
what is the common name for pubic lice?
crabs
50
why do pubic lice prefer the pubic regions?
they are adapted to grasp hairs that are rather widely spaced from each other
51
how is pthiriasis usually spread?
through sexual contact
52
what would kill pubic lice?
lice-killing lotion
53
what do you do after killing the pubic lice?
you have to comb them out with a fine toothed comb because most nits will still be attached to the hair