Parasitology: Fleas and Lice Flashcards
What order do fleas belong to?
Siphonaptera
What parasite is associated with Order Siphonaptera
fleas
What order do lice belong to?
Phthiraptera
What parasite is associated with Order Phthiraptera
lice
What order do flies generally belong to?
Diptera
What parasite is associated with Order Diptera
flies
What order do “true bugs” belong to?
Hemiptera
What parasite is associated with Order Hemiptera
true bugs, such as bed bugs or kissing bugs
What order to tick and mites belong to?
Acari, of the Class Arachnida
In general, what is the body structure of an insect?
3 parts: the head, thorax, and abdomen
In general, how many legs do the adults and, if present, larval stages of insects have?
adults: 6
Larvae: 6
In general, what are the life stages of an insect?
egg -> larvae (may go through instars) -> adult
In general, what is the body structure of ticks and mites?
2 parts: an idiosoma and a gnathosoma
In general, how many legs do the life stages of ticks and mites have?
adults: 8
Nymphs: 8
Larvae: 6
In general, what are the life stages of ticks and mites?
egg -> larva -> nymph -> adult
T/F: Both insects and Acarines contain important disease vectors
True
T/F: The salivary glands of insects and Acarines often harbor pathogens
true
Oxygen diffusion typically occurs through ____ in insects and acarines
spiracles
T/F: spiracles are sometimes used in identification
true
In insects, where do the legs attach?
at the thorax
What is complete development/metamorphosis?
development in which the larva bears no resemblance to the adult
What is incomplete development/metamorphosis?
larva looks like a small adult
Describe the lifecycle of the flea.
egg -> larva -> pupa -> adult
T/F: Fleas are laterally expanded.
False
Fleas are laterally compressed
Geographic distribution of fleas
worldwide
What is the scientific name of the cat flea?
Ctenocephalides felis
do Fleas undergo complete or incomplete metamorphosis?
complete
Do fleas have wings?
nope, they’re just hella good jumpers
T/F: Fleas are macroscopic and yellow
False
Fleas are macroscopic and generally brown
T/F: Ctenocephalides felis is the most common flea of the dog and cat
true
Do immature flea stages prefer cool temperatures and low humidity?
no, they prefer warm temperatures and high humidity
What are C. felis considered once on the host?
permanent ectoparasites
Do eggs laid on the host fall off or stay on? How soon do they usually hatch?
fall off
within a few days
What do flea larvae look like?
slender, white, 2-5 mm in length, may have a dark appearance from blood in intestine
How long are fleas in their larval stage?
about 1 week
Are flea larvae generally mobile?
they have very limited movement
What do flea larvae eat?
organic debris, but require flea feces
T/F: the pupal stage of the flea is not killed by pesticides.
true
T/F: the time spent in the pupal stage is dependent on the environment
true; if the environment is warm and humid, an adult can emerge in roughly 5 days. However, adults can stay in pupa for several months
What is the total length of life in a flea under PERFECT conditions? What stages does the flea spend most of its life?
roughly 2 weeks; egg-> pupa
Can fleas stages survive sustained cold weather?
no, they’re killed within 10 days at 37 degrees F
Where do fleas stay to survive the winter environments?
homes and on reservoir hosts
How is a C. felis infestation diagnosed?
Through observation.
- can see some flea dirt
- clinical signs including pruritis
T/F: it is easy to convince a client that fleas are present
bahahahaha
False. Fucking false.
What are some clinically important aspects of flea infestation?
- it is a common cause of vet visits
- you often see hypersensitivity reactions to flea saliva antigens (range of pruritis and hair loss)
Where are fleas typically distributed on the host?
tailhead, thighs, abdomen, neck
What other infections can fleas be a vector for?
- Dipylidium caninum (tapeworm)
- Bartonella henselae and other Bartonella spp. (cat scratch fever)
- fleas can also cause anemia in young animals
Integrated flea control for fleas on animals includes….
- flea control
- adulticides
- products affecting eggs and larvae administered to animals
Environmental flea control includes….
- Vacuuming!!!
- laundering pet bedding, etc
- traps, sprays, foggers, etc.
- desiccant compounds
Can you expect to have a high level of flea control outdoors?
nope
What are good hosts for C. felis?
- dogs, cats, ferrets,
- not humans, because we don’t sustain their life cycles
- calf and goat infestation likely originated from barn cats
T/F: Other flea species are species-specific.
true
what is the flea species of poultry?
Echidnophaga gallinacea
What is the flea species of humans?
Pulex spp.
These can also be found on dogs and cats
What are the characteristics of lice?
The following are true across hosts:
- small
- wingless
- dorsventrally flattened
- often white or gray, some are brown
- incomplete metamorphosis
What are the two types of lice?
- Anoplura
- Mallophaga
Which type of lice is considered the sucking lice
Anoplura
What type of lice is Anoplura considered?
the sucking lice
Which type of lice is considered biting or chewing lice?
Mallophaga
What type of lice is Mallphaga considered?
Biting or chewing lice
T/F: Lice are very host specific
true
What is the geographical distribution of lice?
worldwide on hosts
Where are lice eggs attached on hosts?
feathers or hairs
What is the minimum life cycle of a louse
3 weeks
How are lice transmitted to other hosts?
Direct contact or fomites
T/F: Lice can survive off of the host for long periods of time
false
T/F: Lice will be worse in winter for outdoor animals.
True
Stressed animals are more or less susceptible to lice infestation?
more susceptible
How do you diagnose a lice infestation?
observation of lice and eggs at predilection sites
clinical signs include: pruritis, hair loss, and poor hair coat
What are some signs of severe lice infestation?
- anemia
- debilitation
Did the lice cause an animal’s disease or did the animal’s disease allow for the lice infestation?
animal’s disease allowed for the lice infestation
Where are lice clinically important?
- common in food animals, poultry, and wild birds
How do you treat lice?
physical removal (self and social grooming, shearing)
- treat to kill adults, then treat in two weeks to kill what came from the egg
- clean potential fomites as much as possible
Should you only treat an infected animal or should you treat all animals when infestation is present?
TREAT ALL ANIMALS
What is the head and body louse of the humans?
Pediculus
What is the pubic louse of humans?
Phthirus
