FILARIAL

Question 1

what order do filarial nematodes belong to?

Answer 1

spirurida

Question 2

where do filarial nematodes usual inhabit in the host?

Answer 2

tendons, vessels, skin, heart

Question 3

what are the characteristic traits of filarial

Answer 3

fine, long (20cm+)
L1 laid into bloodstream
indirect

Question 4

what is the name of the canine heart worm?

Answer 4

dirofilaria immitis

Question 5

what is the basic lifecycle of dirofilaria?

Answer 5

L1 (microfilariae) laid into blood
mozzie ing L1
moults to iL3 in mozzie
iL3 into host when mozzie bites
iL3 --> L4 --> abdomen 
L5 (2mths later) --> penetrates the pulm vein
9mths before more microfilariae

Question 6

why are dirofilarial infection difficult to determine?

Answer 6

9mths + breeding cycle means rare to find microfilariae in blood (so cant detect patent infection)

Question 7

what is the pathogenesis of d. immitis?

Answer 7

exercise intol
cough
dypnoea
R-sided CHF
caval syndrome in CKCS

Question 8

what test is used to detect patent d. immitis infection?

Answer 8

knott test and acid phosphatase stain can ID microfilariae in smear

Question 9

name the 2nd filarial nematode from the ‘old world’

Answer 9

d. repens

Question 10

how do you prevent filarial infections?

Answer 10

MLs mthly
limit mozzie transmission - repellant
adult infection required organoarsenical but risk of thromboembolism
can use doxycycline + IVM

Question 11

where is d. immitis found

Answer 11

RV, PA and cd vc