Ticks and Tick-borne Disease

Question 1

What are the features of ticks and how do they differ from insects?

Answer 1

Ticks are arachnids, NOT insects. Cephalothorax and abdomen, or completely fused body. 8 legs. NO antennae, and NO wings.

Question 2

What are some features of soft ticks (Argasidae)?

Answer 2

Mouth parts cannot be seen from dorsal view. NO scutum. Take multiple, small blood meals. Lay multiple batches of eggs.

Question 3

What are some features of hard ticks (Ixodidae)?

Answer 3

Mouth parts are visible from dorsal view. Have scutum, but females only have partial scutum. Feed for approx. 1 week, lay ONE large batch of eggs (>20000). Sexual dimorphism.

Question 4

Palp

Answer 4

Appendage found on the mouth (capitulum) of invertebrates. DOES NOT go into the skin when tick feeds.

Question 5

Hypostome

Answer 5

Serrated edges on the mouthparts (capitulum), which help anchor the tick into the skin.

Question 6

How many legs do tick larval stages have?

Answer 6

6

Question 7

How many legs do tick nymphs have?

Answer 7

8

Question 8

How many nymphal stages do soft and hard ticks have?

Answer 8

Soft ticks: 2 or more

Hard ticks: Only 1

Question 9

Argas

Answer 9

Soft tick sp.
Feeds on birds and bats.
Morphology: Flat body and suture line!

Question 10

Ornithodoros

Answer 10

Soft tick sp.
Feeds on mammals.
Round body, NO suture line. Long, well-developed mouth parts.

Question 11

Otobius megnini

Answer 11

Soft tick sp.
Feeds on cattle and horses.
Nymphal tegument is spiny. Short mouth parts (NO adult feeding).

Question 12

Ixodes

Answer 12

Black-legged tick.
White-tailed deer and livestock, plus other animals.
Eastern USA
Anal groove in FRONT of anus.

Question 13

Amblyomma americanum

Answer 13

Lone Star Tick
SE USA
Wide host range.
Anal groove behind anus

Question 14

Amblyomma maculatum

Answer 14

Gulf Coast Tick
SE USA
Cattle
Anal groove behind anus

Question 15

Dermacentor variabilis

Answer 15

American Dog Tick
NOT out west.
Canine 
Capitulum base does NOT laterally protrude.
7 caudal festoons.

Question 16

Dermacentor andersoni

Answer 16

Rocky Mountain Dog Tick
Everywhere that D. variabilis is NOT located.
Deer, cattle, and sheep.
Morphology same as D. variabilis.

Question 17

Rhipicephalus sanguineus

Answer 17

Brown Dog Tick
Does NOT tolerate cold weather.
Base capitulum protrudes laterally. Festoons present and anal groove.

Question 18

Rhipicephalus (Boophilus) annulatus

Answer 18

Cattle Tick
Eradicated from USA.
Cattle
Same capitulum as R. sanguineus, NO festoons. 
REPORTABLE DISEASES!!!

Question 19

Rhipicephalus (Boophilus) microplus

Answer 19

Southern Cattle Fever Tick
Eradicated from USA
Wider host range than R. annulatus.
Same as other Boophilus. 
REPORTABLE!!

Question 20

Haemophysalis

Answer 20

Rabbit Tick
WIdely distributed.
Rabbits
Second segment of palp wider than capitulum base.

Question 21

Tick poisoning/toxicosis

Answer 21

Argas soft ticks.
Dermacentor and Amblyomma
Acute ascending flaccid paralysis caused by toxin in tick saliva.

Question 22

Powassan encephalitis transmitted by:

Answer 22

Ixodes spp.

Question 23

Nairobi Sheep Disease transmitted by:

Answer 23

Various hard tick spp. REPORTABLE!!!

Causes hemorrhagic gastroenteritis.

Question 24

African Swine Fever transmitted by:

Answer 24

Ornithodoros soft tick.

REPORTABLE!!! Systemic hemorrhagic disease.

Question 25

Lyme Disease transmitted by:

Answer 25

Ixodes scapularis --> Eastern US Ixodes pacificus --> Western US Causative agent: Borrelia burgdorferi

Question 26

Tularemia transmitted by:

Answer 26

Dermacentor and Amblyomma americanum. Agent: Francisella tularensis Mid-west disease.

Question 27

Heartwater transmitted by:

Answer 27

Amblyomma Reportable!!!! Agent: Ehrlichia ruminantium

Question 28

Canine granulocytic ehrlichiosis transmitted by:

Answer 28

Amblyomma | Agent: Ehrlichia ewingii

Question 29

Tropical Canine Pancytopenia transmitted by:

Answer 29

Rhipicephalus sanguineus | Ehrlichia canis

Question 30

Canine cyclic thrombocytopenia transmitted by:

Answer 30

Rhipicephalus sanguineus | Anaplasma platys

Question 31

Granulocytic anaplasmosis

Answer 31

Ixodes spp. | Anaplasma phagocytophilum

Question 32

Bovine Anaplasmosis

Answer 32

Dermacentor --> Western US

Question 33

Rocky Mountain Spotted Fever

Answer 33

Dermacentor | Rickettsia rickettsi

Question 34

Hepatozoonosis

Answer 34

Amblyomma maculatum (severe)/Rhipicephalus sanguineus (mild). Ingestion of tick vector Onion skin cysts. Death 1-2 yrs PI, if untreated.

Question 35

Theileriosis

Answer 35

``` Cytauxzoon felis (Amblyomma) Theileria equi (REPORTABLE) ```

Question 36

Babesiosis

Answer 36

B. canis/B. gibsoni --> R. sanguineus B. caballi --> Dermacenter, Hyalomma, Rhipicephalus. REPORTABLE!!! B. bigemina/B. bovis --> Rhipicephalus spp. REPORTABLE!!!!

Question 37

Features of Mites

Answer 37

Arachnids | Several nymphal instars.

Question 38

Sarcoptes scabiei

Answer 38

``` Scabies mite --> Sarcoptic mange ONE species w/ host adapted variants WIDE host range (cats are rare) Alopecia, prurities, self-tramua, secondary infections. BURROWS DEEP INTO SKIN ```

Question 39

Sarcoptic mange

Answer 39

Dog --> Itch Mite. Lat elbows, hocks, pinna Cattle --> Barn Itch. Abdomen, neck, med hind legs Sheep/Goats --> Head Scab. Face, ears, ventrum (REPORTABLE) Horses --> Neck, shoulders, face (REPORTABLE) Pigs --> Ears, back

Question 40

Notoedres cati

Answer 40

Notoedric Mange Wild and domestic felids Head and neck, similar to sarcoptic mange.

Question 41

Psoroptes spp

Answer 41

P. cuniculi --> Common ear mite. Spp in large animals are REPORTABLE!!! Back, neck, tail head, and shoulders.

Question 42

Chorioptes spp

Answer 42

Foot and tail mange of large animals. MOST COMMON | Mild to no clinical signs.

Question 43

Otodectes cynotis

Answer 43

Ear mites. Zoonotic Trauma is usually bilateral

Question 44

Demodex

Answer 44

NOT zoonotic!! Species specific in hair follicles. Immunosuppression may cause overgrowth. Squamous and papulonodular disease.

Question 45

Cheyletiella

Answer 45

"Walking dandruff" | Dogs/cats

Question 46

Pneumonyssoides

Answer 46

Canine nasal mite | Rhinitis/hyperemic mucosa.

Question 47

Fleas

Answer 47

Blood feeders w/ host preference. Bilaterally flattened, chitinized, wingless. Cause direct and indirect disease.

Question 48

Lice

Answer 48

Suborders: Mallophaga - Chewing/Biting Lice Anoplura - Sucking Lice HOST SPECIFIC!!!!!