Parasitology 2 - Fleas, Lice, Flies

Question 1

Which group do these organisms belong to?

Answer 1

The insects which are under the arthropods

Question 2

Give some characteristics of insects

Answer 2

• 3 pairs of legs
• Head, thorax, abdomen
• Incomplete or complete metamorphosis

Question 3

What do fleas look like?

Answer 3

Dark brown, wingless, 3 pairs of legs that are enlarge for adaption of leaping, laterally compressed bodies

Question 4

What is the lifecycle of fleas? How long is their complete life cycle?

Answer 4

-Eggs drop off where host rests
-Larvae inhibit floor crevices, carpets, bedding
-Emergence from cocoon can take up to 6 months
-Unfed, newly emerged adults may survive for weeks
Complete life cycle: 3-4 weeks to 2 years. (complete metamorphosis)

Question 5

Which fleas infest dogs and cats?

Answer 5

ctenocephalides felis (most common on dogs) and ctenocephalides canis

Question 6

What are the clinical significance of fleas?

Answer 6

-Flea allergy dermatitis (FAD)
pruritus, alopecia, crusty lesions and sometimes secondary bacterial infections
-Can cause anaemia
-Intermediate hosts for some zoonotic pathogens

Question 7

What are some characteristics of lice?

Answer 7

-Wingless, dorso ventrally flattened, walk dont jump, two types: chewing lice, sucking lice

Question 8

What is the life cycle of lice? How long?

Answer 8

-Adult cement eggs into hair shafts
-Nymph hatches from eggs, takes 3 moults until adults stage
Life cycle is 4-6 weeks (incomplete metamorphosis)