Parasites of The Cardiovascular system Flashcards

1
Q

What is microfilaria?

A

Non-digestive roundworm (heartworm)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How long is the average male and femal microfilaria respectively?

A
  • Males are 15cm
  • Females are 25cm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How long do microfilariae live for in dogs and how long are the dogs patent for?

A
  • They can live for up to 7.5 years
  • dogs can be patent for 5 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is Wolbachia endosymbiont?

A
  • intracellular bacterium found in many filarial worms
  • can have a mutalistic or symbiotic relationship
  • Harboured by all stages of Dirofilaria immitis
  • Required for fertility, survival & development of D. immitis
  • Role in pathogenesis unclear
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the primary host of dirofilariae?

A

Domestic Dog

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the pre-patent period of dirofilariae?

A

6 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

At what point in the dirofilariae lifecycle are they infectious to other dogs?

A

L3 stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name three mosquitos that are important intermediate hosts of dirofilariae?

A
  • Aedimorphus vexans
  • Culex pipens pipiens
  • stegomyria albopicta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does dirofilariae pathology depend on?

A
  • Number of worms
  • infection duration
  • host immune response
  • Host activity (more active host= more strain on heart= more suffering)
  • Dog size (smaller dog= smaller vessels= increased illness)
  • dead worms cause a more severe reaction than live worms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do adult dirofilariae worms do once released into pulmonary arteries?

A
  • trauma and release of antigens
  • irritation of arteries and stimulation of immune system
  • endothelial damage, tunica intima, proliferation, perivascular cuffing
  • vessel narrowing/ occlusion, reduced vascular compliance
  • pulmonary hypertension
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the long term sequelae of dirofilariae in pulmonary arteries?

A
  • pulmonary hypertension and inflammatory mediators
  • increase in pulmonary vessel permeability
  • periarterial oedema, lung inflammation
  • irreversible interstitial fibrosis and scarring
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does worm death cause?

in terms of blockage

A

pulmonary thromboembolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is vena caval syndrome?

A

Worms found in the right side of the heart and vena cava
* causes tricuspid valve problems and blood flow obstruction
* right-sided heart failure

Flow of red blood cells through worms -> haemolysis and haemoglobinaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What may a lighter difilaria infection look like in a dog?

A
  • Asymptomatic
  • Causes sustained exercise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What may a heavier difilaria infection look like in a dog?

A
  • Loss of condition and exercise intolerance
  • Chronic cough, shortness of breath
  • Oedema and ascites
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the clinical signs of vena caval syndrome in dogs?

A
  • Haemoglobinuria
  • Jaundice
  • Collapse
  • May be fatal
16
Q

Why is there a strong inflammatory response in cat heartworm?

A

Most immature worms in pulmonary arteries die
* migration of worms to the CNS and other body cavities can occur

17
Q

What are the clinical signs of heartworm associated respiratory disease in cats?

A
  • Occurs 3 months post-infection
  • dyspnoea, coughing, wheezing
  • no adult worms are present
18
Q

What are the clinical signs chronic feline heartworm disease?

A
  • over 7 months post-infection
  • respiratory signs, vomiting, neurological signs, pulmonary hypertension and heart failure, sudden death
  • adult worms in pulmonary artery and heart
19
Q

How may you diagnose feline heartworm disease?

A
  • Geographical location
  • Clinical signs
  • Thoracic radiography
  • Echocardiography
  • routine lab testing ( anaemia, eosinophillia, proteinuria)
20
Q

What are some more specific tests you can use for diagnosing worms in cats?

A
  • Antigen testing- detect proteins from the reproductive tract of adult females
  • Microfilariae in blood testing
  • Antibody tests
21
Q

What drugs can you use to prevent/ control dirofilariae?

A
  • Chemoprophylaxis uses anthelmintics
  • Larvicidal and interrupts reproductions (only kills of larvae and not adults)
  • You can treat monthly from 2-3 months of age
  • but does require testing before treating an older dog
22
Q

How can you use vector control to prevent dirofilariae?

A

Should use routine use of mosquito repellents and insecticides on pets (any product with a 4+ week persistence)

23
Q

In what countries is there potential chemoprophylaxis resistance?

A
  • Well accepted in the US
  • No strong evidence of resistance in Europe
  • Continued surveillance is needed
24
Q

What is the only effective treatment of adult worms in dogs?

A

arsenical compound melarsomine dihydrochloride
* must confine dogs for one month afterwards

25
Q

How can you cure vena caval syndrome?

A

Requires a surgery to remove the worms

26
Q

What do dirofilariae infections look like in humans?

A
  • Generally asymptomatic
  • can cause pulmonary coin lesions
  • may cause coughs, chest pain, fever, pleural effusion
  • ocasionally fatal
27
Q

Name four other parasites of the CV system

A
  • Strongylus vulgaris
  • Ascaris
  • Toxocara
  • Sarcocystis
28
Q

What can cause schistosomiasis?

A

Causes by blood fluke- shistosomes

29
Q

What are the infection reservoirs of schistosoma japonicum?

A
  • water buffalo, cattle, rodents, dogs, sheep, pigs
30
Q

When are ruminants mostly exposed to schistosomes?

A

through contact with infested waterbodies

31
Q

How do the Cercariae penetrate?

A

They directly penetrate the skin

32
Q

What are the clinical signs of ruminant schistosomiasis?

A
  • Weight loss, diarrhoea, anaemia, hypoalbuminaemia, hyperglobulinaemia, and severe eosinophillia
  • severley affected animals deteriorate rapidly and die
  • less heavily infected animals develop chronic disease with poor growth
33
Q

What occurs when RBC’s flow through worms?

A

Haemolysis and haemoglobinaemia