fleas and lice

Question 1

most important louse

Answer 1

pediculus humanus- body louse

Question 2

distinguishing features of lice

Answer 2

wingless, teeth, mouthparts
body and hair: long body
pubic: dorsally ventrally flattened and claws

Question 3

life cycle lice

Answer 3

1. white operculated egg on hair
2. 3 instar nymph
3. adult
   all stages blood feed

Question 4

control of lice

Answer 4

insecticides with permethrin
comb hair
iron or hot wash clothing

Question 5

body lice transmit…
parasite
how are they transmitted

Answer 5

1. louse-borne epidemic typhus
   - rickettsis prowazekii
   - faeces of louse
2. trench fever
   - bartonella quintana
   - faeces of louse
3. relapsing fever
   - borrelia recurrentis
   - louse crushed enters mucosa

Question 6

fleas order

Answer 6

siphonaotera

Question 7

4 types of flea

Answer 7

Xenopsylla - tropical rat flea
Pulex-human flea
ctenocephalides- cat and dog fleas (combed)
Tunga penetrans- jigger flea

Question 8

how to tell differenc between xenopsylla and pulex

Answer 8

xenopsylla has meral rod ‘hipline’

Question 9

distinguishing features of fleas

Answer 9

hindlegs for jumping
mouthparts for piercing skin
wingless
small

Question 10

life cycle of fleas

Answer 10

eggs laid from host, larvae feeds on debris, cocoon containing pupa, adult

Question 11

control of fleas

Answer 11

insecticide treatment of domestic animals, carpets, domestic rat runs, rodent control, treat human infestations

Question 12

fleas transmit…
pathogen
how trasnmitted

Answer 12

1. plague
   yersinia pestis
   brown sewer rat and black domestic rat
2. tapeworm infections
   flea larvae eat animal faeces containing eggs
3. endemic typhus (murine typhus)
   rickettsia typhi
   flea faeces and bites
4. jigger fleas
   female burrows into skin and swells up to pea size- painful nuisance