Lice and Fleas

Question 1

What are the three types of human lice?

Answer 1

Pediculus humanus capitis (head louse)
Pediculus humanus corporus (body louse)
Pthirus pubis (pubic/crab louse)

Question 2

Which lice type is known to spread disease?

Answer 2

only the body louse

Question 3

How are lice spread?

Answer 3

through person-person contact, NOT through animals

Question 4

How do lice move?

Answer 4

crawling. cannot hop or fly

they are wingless but have claws

Question 5

What are some defining physical characteristics of lice?

Answer 5

wingless
have 6 legs
antennae have no more than 5 segments
abdomens are longer than wide

Question 6

How can head lice potentially cause disease?

Answer 6

secondary bacterial infections caused by scratching

Question 7

What do adult head lice do to avoid detection?

Answer 7

they can change colour to be the same as the host’s hair

Question 8

How can you get rid of head lice?

Answer 8

use insecticide shampoo for the adults, and use a nit comb to pull out the nits from the hair

Question 9

How long does it take for the nits to hatch?

Answer 9

one week

Question 10

Where do body lice live?

Answer 10

in the seems and linings of unwashed clothing, blankets and sheets.
only move to the skin to feed because people do not usually have a lot of body hair

Question 11

When will body lice die?

Answer 11

after 1-2 weeks of not having a blood meal

Question 12

Which diseases can body lice spread?

Answer 12

epidemic typhus, trench fever, and louse-borne relapsing fever

Question 13

How can linens be rid of body lice?

Answer 13

washing in very hot water

Question 14

Where on the body are pubic lice found?

Answer 14

attached to coarse hair, including pubic hair, eyebrows, eyelashes, beard, moustache, chest, armpits, etc
their bodies are wider and their legs further dispersed to grasps these hairs

Question 15

How can you be rid of pubic lice?

Answer 15

using insecticide shampoo and a nit comb for the eggs

Question 16

When will pubic lice die?

Answer 16

after 24-48 hours of not having a blood meal

Question 17

What are the distinctive features of fleas?

Answer 17

6 legs
wingless
have long hind legs that allow them to jump
a disproportionate small head
bodies are laterally compressed
no attaching appendages

Question 18

What kind of pathogens can fleas transmit?

Answer 18

bacteria (bubonic plague), protozoa, and helminthes (Dipylidium caninum)

Question 19

What are the four main species of fleas that infest humans?

Answer 19

cat flea: Ctenocephalides felis
dog flea: Ctenocephalides canis
human flea: Pulex irritans
rat flea: Xenopsylla cheopis

Question 20

How can the cat and dog flea be differentiated?

Answer 20

the cat flea has mouth combs that are approximately all the same length
the front dog comb is half the length of the second comb

Question 21

Which diseases can Ctenocephalides species cause?

Answer 21

rickettsial diseases including Rickettsia typhi
also spotted fever, typhus, and scrub typhus
intermediate hosts for some tapeworms

Question 22

How can the human flea species be distinguished from the rest?

Answer 22

it does not have any combs

Question 23

What does the human flea do?

Answer 23

salivary proteins can cause allergic reactions

Question 24

What diseases does the rat flea transmit?

Answer 24

bubonic plague (Yersinia pestis) and endemic typhus (aka murine typhus)

Question 25

Does the rat flea have ctenidia (combs)?

Answer 25

no

Question 26

How can flea infections be treated?

Answer 26

itching can be treated with antihistamine or hydrocortisone creams
using dehumidifiers (eggs need humidity to hatch) + air conditioning (adults need a certain temp) + vacuuming