[BowWowMeow]

Hoping someone might know the answer here...

How long does it take for heartworm to show up? Rafi tested negative for heartworm in early December. As far as I know he has never been on preventative (extremely doubtful judging from the condition he was in when found). I am wondering if I should have him tested tomorrow when I take him to the vet. Do you think that's necessary or if he were infected in August, September, or October (when he was on his own) would it show up on a test in early December?

Thanks!

 

[JenM66]

Are you planning on starting him on heartworm meds? Yes, he should be tested prior to starting since he has not been on anything consistently. At work, we check annually before renewing prescriptions. Dogs who have consistently been on meds we may do a 2 year check. It's a quick test for piece of mind. Has he been coughing at all?

 

[DancingCavy]

I believe it takes about 6 months for heartworms to show up on a blood test. Not 100% sure. Best bet is to ask your vet.

 

[BowWowMeow]

He's not showing any signs of heartworm and he has not been exposed to any mosquitoes since October.

My vet tests every 3 years if you are on preventative (not year round since we don't have mosquitoes year round here).

I do remember being told at some point that it is wise to retest rescues after 6 months. I guess I'll just do it to be safe.

 

[JenM66]

Since we live in NJ and the state bird is the mosquito

we recommend being on prevenatives year round. There don't seem to be seasons here anymore, as we had 70 degree days in December and today it is 52. I think it's a good idea, just to be safe, a simple little blood draw - will they do the 4DX to check for tick borne illnesses also?

 

[MLinn730]

It takes 6 months for the larva(?) that is transmitted from the mosquito to turn into an adult heartworm. That is why vets don't test puppies under six months of age, it is impossible for them to have adult heartworms. If the dog is started on HW prevention before the larva turn into adults, it will kill them with no harm to the dog.

New studies are also saying that HW prevention can be another method of treating HW infection, but I personally would like to see more research before using that method to treat my dogs.

Back to the question though...Lets say your rescue was bitten by a HW positive mosquito in September, the test would be negative in December. If you started him on HW prevention in December, there is no need to retest him. If not though, and he was infected in say Sept., then you would need to retest to make sure that he is still ok to start on HW prevention. The risk is that if he does have adult HWs and you start prevention it could cause your dog to become very very sick.

 

[BowWowMeow]

That's what I thought. And no I didn't put him on preventative because I only give it June through November. We don't have mosquitoes here year round and I am very conservative about poisoning my dogs.

The vet does do the tick test with the heartworm test.

 

[Maedchen]

I would definitely test him now!
Otherwise you'll always wonder...

 

[NoVA_Dawg]

Originally Posted By: WorkingK9s If you started him on HW prevention in December, there is no need to retest him. If not though, and he was infected in say Sept., then you would need to retest to make sure that he is still ok to start on HW prevention. The risk is that if he does have adult HWs and you start prevention it could cause your dog to become very very sick.

That is not entirely true. When we adopted Gracie it was January and she had tested negative that November when she was tested by the Humane Society. She had been on heartworm prevention (Interceptor) from the date of her negative test, yet at her annual exam the following November she came back positive. X-rays showed enlargement of the heart and some strain on the lungs. We had to go through 3 injections. I would defiantly have him tested…heartworm treatment is no fun, but it is better to know as early as possible and be able to limit activity in a young active dog so they don’t damage their heart and lungs permanently. At the time I did not know that it took 6 months to show up on a test. If I did, I would have had her re-tested earlier.

Edited to add: I forgot to mention she showed NO signs of heartworm...the vet and I were shocked when the results came back positive.

 

[BowWowMeow]

Thanks, everyone. I've read several other cases where a dog tested negative and then positive a few months later so I'm going to have him tested tomorrow just to be sure.

 

[middleofnowhere]

(6 mos is the right figure.)