Vet Stumed About Bunny Worms

Question
I have a young female Lop Eared Bunny.  We got her about 7 mos ago and she was a baby.  She was checked by the vet when we first got her and again about 2 mos ago when I took her to have her nails clipped.  She has always been a house rabbit.  About a week ago, she was out running around and playing with us and she dropped a few pellets. My daughter called me over when she picked one of them up and saw a small thin whitish worms on it.  It was very tiny and almost looked like a pinworm.  I took the droppings along with the worm to the vet the next morning and they sent it out to a lab that returned a negative result.  This puzzled the doctor and I because we both saw this worm.  So today I took in another sample with another very visible worm and another doctor that has experience with rabbits looked at it as well as the droppings under a microscope.  She also did the test fecal floatation test.  She said she saw very visible worms, but no eggs.  She also said it doesn't look like an intestinal worm to her, and that she would have expected to have a positive result from the floatation test.  We are both stumped, and she seems to think that it could be "lung worms".....I feel horrible for our bunny.  This sounds serious to me and I am also concerned because I have small children. Our Vet doesn't seem to concerned about tranmission to any of us, but until we are sure, I have her "quarantined" in my laundry room. She has been kind of wheezing off and on and in the last 2 weeks she has been rubbing her neck on everythig she can, like her throat is scratchy.  Anyway, the doctor is doing some checking with a specialist, but in the meantime, I figured I'd ask if you had any information about this sort of thing.  I love our bunny so much!  She is a member of our family, and I have never really felt this way about a pet before.  I want to make sure she is okay and that no one else is at risk.  Thank you!  Kelly  

Answer
Dear Kelly,

I've never heard of a domestic rabbit being infected with lungworms, but there are various species of this type of nematode parasite that can take up residence in many different species, so it's not impossible.  The lungworm diagnosis would be consistent with finding worms in the feces, but no eggs, since the larvae are swallowed by the host only after they hatch and crawl up into the throat.  (YUCK!)

Normal treatment for these parasites is Panacur (fenbendazole), which is safe for rabbits.  This should also be effective against many other species of nematodes, so please ask your vet about starting the bunny on Panacur to get her back to normal ASAP.

I agree with the vet that there is very, very little chance of you or your family contracting these parasites. They usually are quite host-specific, and they should  not be able to infect a human with a normal immune system.

I hope your vet is able to get to the bottom of this mystery soon, but I hope also in the meantime that the bunny will get some Panacur and be on the road to recovery.  If the vet wants a positive I.D., then samples of the worms should be sent to a good parasitology lab at a university.

I'm sure your bunny will be fine.  I just hope she gets treated ASAP.

Hope this helps.

Dana