Ectoparasites V: Fleas and Lice Flashcards
Are fleas insects or arachndis?
Insects
What are fleas the best at in the animal kingdom?
Jumping
What are characteristics of fleas?
Bilaterally flat, chitinized, wingless
Combs on some species
Blood feeders with host preferences
What is the flea life cycle?
Complex metamorphosis
Eggs are laid on host but fall off into the environment
Hatching in environment takes 2-5 days
1 stage larvae feed on organic matter to become 2nd stage larvae
3rd stage larvae become pupa in a silk cocoon with debris on outside
Adults emerge after 1-2 weeks in environment; delayed emergence up to 4 months
Adult has several blood meals per day and lays 25-40 eggs/day
How can you diagnose “pulicosis”?
History: evidence of fleas or pruritus
Exam: evidence of fleas, eggs, larvae; evidence of flea feces
May cause hypersensitivity reaction
What is the species of the cat flea?
Ctenocephalides felis
What is the species of the dog flea?
Ctenocephalides canis
What is the species of the human flea?
Pulex irritans
What is the species of the sticktight flea?
Echidnophaga gallinacea
What is the species of the oriental rat flea?
Xenopsylla cheopis
What is the host of Ctenocephalides felis?
Wide range of hosts, but prefers cats
What is the worldwide distribution of Ctenocephalides felis?
Most common ectoparasite of dogs and cats in North America
Uncommon in arid areas
What kind of disease can Ctenocephalides felis cause?
Direct and indirect
How does Ctenocephalides felis infestation occur?
Adults emerge from pupae with mechanical CO2, temperature cues
Begin feeding immediately
Females begin egg-laying in a day
Larvae desiccate easily
How much blood can a Ctenocephalides felis ingest per day?
13.6 μL
What are the hosts of Ctenocephalides canis?
Narrow host range compared to C. felis
Mainly canids
What are the hosts of Pulex irritans?
Mainly humans, swine, and dogs
What is the distribution of Pulex irritans?
Worldwide, but patchy areas
What are the unique characteristics of Pulex irritans?
Lack combs
Ocular bristle
What are the hosts of Echidnophaga gallinacea?
Poultry (and other birds)*
Dogs, cats, and other species
What is the distribution of Echidnophaga gallinacea?
Mainly in tropical areas
What are the unique characteristics of Echidnophaga gallinacea?
Small size
Lack combs
Angled head
Describe the direct disease process of Echidnophaga gallinacea?
Infest bare areas— ulcers— anemia, secondary infections
What are the hosts of Xenopsylla cheopis?
Rats*
Humans
Dogs
What is the distribution of Xenopsylla cheopis?
Tropic and subtropics
What are the unique characteristics of Xenopsylla cheopis?
Lack combs
Ocular bristly
What are flea-associated direct diseases?
Flea allergy dermatitis
Anemia
What are flea-associated indirect diseases?
Cestodes
Nematodes
Bacteria
Viruses- myxoma viruses
What is flea bite hypersensitivity?
Allergic reaction to antigens in flea saliva
What is the most common cause of pruritus in dogs and cats?
Flea bite hypersensitivity