Vector mediated Apicomplexa

Question 1

Hepatozoon species use what for definitive host and what for vectors?

Answer 1

blood feeding insects for both

Question 2

What cell type does Hepatozoon species infect?

Answer 2

Leukocytes

Question 3

How do animals become infected with Hepatozoon?

Answer 3

Ingesting the intermediate host

Question 4

What is the species that causes American canine hepatozoonosis?

Answer 4

Hepatozoon americanum

Question 5

What transmits Hepatozoon americanum?

Answer 5

Gulf coast tick

Question 6

When dogs are the _____ for Hepatozoon americanum, they can become sick

Answer 6

intermediate host

Question 7

What is the life cycle of Hepatozoon americanum in the tick?

Answer 7

Takes up gamonts via leukocyte ingestion

Sporulated oocysts develop in the tick

Question 8

Describe the life cycle of Hepatozoon americanum in the dog

Answer 8

Infected via ingestion of the tick containing oocysts
Sporozoite infects macrophage; may reside in onion skin cysts
Merogony takes place in the cyst between muscle layers
Gametogony happens in monocytes

Question 9

What are the clinical signs in a dog infected with Hepatozoon americanum?

Answer 9

Fever that is intermittent due to merozoite release –> local inflammation and systemic reaction
Myalgia, myasthenia, and are reluctant to move

Question 10

How would you diagnose Hepatozoon americanum?

Answer 10

Muscle biopsy looking for cysts

Question 11

T/F The best treatment for this is metronidazole

Answer 11

FALSE; this is something they will likely just have to learn to live with

Question 12

What are the three important Piroplasms we need to know?

Answer 12

Babesia spp.
Theileria spp.
Cyatauxzoon spp.

Question 13

What is a unique feature of Piroplasms?

Answer 13

Only asexual phase is seen in vertebrates

Sporozoites are injected with the tick bite

Question 14

What is the definitive host of Babesia? How is it transmitted?What are the IH we are concerned with?

Answer 14

Ioxid tick
Tick bite
Dogs, cattle, and horses

Question 15

What is the life cycle of Babesia?

Answer 15

Gametogony occurs within tick, innoculates host with sporozoites with bite.
Directly infects RBCs of host
Develop into prioplasms and replicate into merozoites
merozoites become gamonts, which are then ingested by the tick when feeding, and lifecycle restarts

Question 16

Where is the one place Babesia motile zygotes can go to cause infections of eggs laid by the tick?

Answer 16

Ovaries

Question 17

T/F Mixed infections usually occur with Babsiosis and immunity is usually species specific

Answer 17

TRUE

Question 18

What are clinical signs that would be seen with Babesiosis?

Answer 18

Signs that are associated with the destruction of RBCs

Question 19

What are the two species that are associated with canine babesiosis?

Answer 19

Babesia canis vogeli

Babesia gibsoni

Question 20

What is Babesia gibsoni associated with?

Answer 20

Dog fighting

Question 21

How would you diagnose babesiosis in dogs? What is the treatment?

Answer 21

Do a blood smear to detect parasites in the RBCs
Supportive care, but generally recover from acute stage
Can treat with Imidocarb diproprionate

Question 22

What species cause bovine babesiosis?

Answer 22

Babesia bigemina

Babesia bovis

Question 23

T/F Babesiosis is a concern for veterinarians in the US

Answer 23

FALSE; has been eradictated due to cattle dipping. Have killed off the tick that spreads it

Question 24

T/F Babesiosis infection has been eradicated from the world

Answer 24

FALSE; it is still present in Mexico

Question 25

What causes equine babesiosis?

Answer 25

Babesia caballi | Theileria equi

Question 26

What is special about Theileria equi?

Answer 26

No transovarial transmission in ticks | Schizonts go to lymphocytes first, then go to RBCs

Question 27

Where is equine babesiosis endemic?

Answer 27

TRopical and subtropical areas

Question 28

T/F equine babesiosis used to be endemic in Texas, but it has been eradicated

Answer 28

FALSE; used to be endemic in FLORIDA. GOTCHA BITCH

Question 29

How would you diagnose equine babesiosis?

Answer 29

Blood smear that demonstrates parasites in the RBCs

Question 30

_____ is a disease of domestic cats in the US that results in rapid onset with a high fatality

Answer 30

Cytauxzoon felis

Question 31

What is the lifecycle of Cytauxzoon felis?

Answer 31

Sporozoites are innoculated via tick bite Schizogony occurs in macrophages throughout the body Merozoites develop in RBCs

Question 32

What are considered to be resevoir hosts for Cytauxzoon felis?

Answer 32

Bobcats

Question 33

Cytauxzoonosis in domestic cats is seen with what history?

Answer 33

outdoor exposure during tick season

Question 34

What are some lesions seen with Cytauxzoonosis in cats?

Answer 34

Splenomegaly, hepatomegaly, and enlarged LNs

Question 35

How would you diagnose Cytauxzoonosis?

Answer 35

Blood smear to demonstrate parasites in the RBC | Usually only see one organism per RBC

Question 36

T/F There has been no treatment shown to be effective against Cytauxsoonosis?

Answer 36

TRUE