Vector borne disease Flashcards
What tick transmits Anaplasma phagocytophilum?
Ixodes scapularies and Ixodes pacificus
Anaplasma phagocytophilum causes what disease?
Canine granulocytic anaplasmosis - infects granulocytes (primarily neutrophils)
What tick transmits Anaplasma platys?
Rhipicephalus sanguineus
Anaplasma platys causes what disease?
Canine cyclic thrombocytopenia - infects platelets
How is Hepatozoon transmitted?
Ingestion of Rhipicephalus sanguineus (H. canis) or Amblyomma maculate (H. americanum) ticks
What are the clinical signs of Hepatozoon americanum infection?
Lethargy, fever, locomotory abnormalities, hyperesthesia, PLN
What organism transmits Leishmania?
Infected female sandflies
Leishmania is endemic in what breed in North America?
Foxhounds
What organism transmits Trypanosoma cruzi?
Feces contaminated bite from or ingestion of triatomine bug vectors (kissing bugs)
Infection with Trypanosoma results in what?
Acute or chronic myocarditis
What ticks transmit Borrelia burgdorferi?
Ixodes scapularis (black legged tick) and Ixodes pacificus (Western Black legged tick)
What tick is this?
Ixodes scapularis
Describe the life cycle of Ixodes ticks
Larva or nymphs feed on infected rodents and become infected; adults feed on deer or dogs and transmit the infection
What outer surface protein does the Borrelia express in the tick midgut?
Osp A
When the tick ingests a blood meal, the Borrelia move to the tick salivary glands and begin to express what outer surface protein?
Osp C
How long must a tick be attached to transmit Borrelia?
~48 hours
When do dogs develop clinical signs of Lyme disease (fever, lameness) after a tick bite?
2-5 months - chronic disease
What is the synovial fluid cytology of a dog with Lyme disease?
Can be normal or have marked numbers of non-degenerate neutrophils (>5000)
What Borrelia antigen does the 4Dx test for?
C6 protein
What characteristics define the order Rickettsiales?
Obligate intracellular bacteria, form morulae within host cells
What cell type is infected by Ehrlichia canis?
Monocytes
What cell type is infected by Rickettsia rickettsii?
Endothelial cells
What tick transmits Ehrlichia canis?
Rhipicephalus sanguineus (brown dog tick)
What tick transmits Ehrlichia ewingii?
Amblyomma americanum (Lone star tick)
What three ticks are capable of transmitting Rickettsia rickettsii?
Amblyomma americanum (Lone star tick), Dermacenter (American Dog tick), and Rhipicephalus sanguineus
What is the cell tropism for Ehrlichia ewingii?
Neutrophils
In the acute phase of canine monocytic erhlichiosis, where are the organisms replicating? How long does this phase last?
- 1-4 weeks
- Replicate in the reticuloendothelial tissues (spleen, LNs)
What are the clinical signs of the acute phase of canine monocytic erhlichiosis?
- Vasculitis, platelet dysfunction and thrombocytopenia lead to bleeding
- Lethargy, inappetence
- Fever
- Lameness (polyarthritis)
What is the outcome of the acute phase of canine monocytic erhlichiosis?
Recover in 2-4 weeks or become a carrier
In the subclinical phase of canine monocytic erhlichiosis, where is the organism sequestered?
In the spleen
What are the clinical signs/pathologic abnormalities in chronic canine monocytic erhlichiosis?
- Pancytopenia (or thrombocytopenia, anemia with marked granular lymphocytosis), bone marrow hypoplasia, marked monoclonal gammopathy
- Fever, weight loss
- Bleeding
- Edema
- Death due to hemorrhage or secondary infections
What clinicopathologic abnormality is seen in all three phases of canine monocytic erhlichiosis?
Thrombocytopenia