Nematodes- Filarioidea

Question 1

Where is the adults of dirofilaria immitis located

Answer 1

Right ventricle, pulmonary arteries

Question 2

Where are the microfilariae found

Answer 2

Circulating in blood

Question 3

What is the vector/IH for Dirofilaria immitis

Answer 3

Mosquitos

Question 4

What is an occult infections

Answer 4

Dog harbors male and/or female adults
Hidden
Mff not detectable
Low numbers

Question 5

What is nocturnal periodicity

Answer 5

Mff present in evening hours

Question 6

what is diurnal periodicy

Answer 6

Mff present during daylight

Question 7

What is complete periodicity

Answer 7

Mff disappear from peripheral blood at sometime during 24hr period

Question 8

What is incomplete periodicity

Answer 8

Mff never disappear completely from peripheral blood during 24 hour period

Question 9

what are heart worm periodicity

Answer 9

nocturnal and incomplete

Question 10

What are hyperendemic areas

Answer 10

40-60% prevalence

nonprotected, outdoor dogs

Question 11

When does Heartworm become detectable consistently

Answer 11

6-6.5 months old

Question 12

What does the heart worm test detect

Answer 12

Antigen

Detection of circulating microfilariae

Question 13

How many species of mosquitoes are common vectors for heart worm

Answer 13

14

Question 14

What could have happened with positive antigen, but negative microfilaria test

Answer 14

1. Maturing infection, no microfilariae in circulation
2. Use of preventative without removing adults
3. Use of microfilaricide without removal of adults
4. only females present
5. Dog is a true immune mediated occult
6. Failure to use microfilaria concentration test

Question 15

What could happen when antigen test is negative, but microfilariae is positive

Answer 15

1. Microfilariae are those of another species
2. Microfilariae were acquired transplacentally
3. adult worms were removed or have died but microfilariae persist

Question 16

What are some clinical signs of Dirofilaria immitis

Answer 16

Vascular resistance
Decreased cardiac output
Coughing and hemoptysis
Vena cava syndrome: infect atrium and vena cava

Question 17

Differences between feline vs. canine heart worm

Answer 17

Feline: less susceptible, fewer worms, few worms can cause disease, usually amicrofilaremic, diagnosis requires multiple tests.

Dogs: Highly susceptible, many worms, worms long lived, usually microfilaremic, heart and lungs, easily diagnosed

Question 18

What’s the scientific name for heartworm

Answer 18

Dirofilaria Immitis