In a word, yes.
Heartworm testing is very important to the health of your dog. If your dog is heartworm positive and you put it on certain types of heartworm preventative, it could have detrimental effects, including death.
I know many of you will say that the pet has been on monthly heartworm prevention, year round as we advise. However, reality tells us that many of you out there (myself included) occasionally miss a month. Let’s face it, we are not all perfect and life happens. When these (rare) occasions occur, it is possible that your pet could be bitten by an infected mosquito and has the potential to become heartworm positive. Just to carry it a step farther, what if the next date comes up, and you can’t remember if you gave it, and you don’t want to overdose Fido, so you decide to wait until next month….
As a Veterinarian, I am pretty sure this happens with some regularity, as I have had many clients over the years that have purchased a 6 month supply 12 months ago, and still they have 4 doses left. And yes I swear this really happens! (More often, the clients have gotten a 12 month supply and have 2-3 doses left, but you see my point)
Another reason for yearly testing is for the small percentage of prevention failure with any heartworm preventative. In one particular case that I remember, the client had 2 dogs and she gave heartgard religiously to them, saw them eat it every month, so knew they were protected. She then came in for a yearly heartworm test, and one of the two was positive. How can this be, she asked? Well, she investigated a little more, and it turned out that the one that became heartworm positive was spitting it out, and the other was getting a second tasty treat!
Heartworm disease is on the increase in our area, especially after the wet rainy summer and fall we had in 2011, and the mild winter in 2012. At Garrettsville Animal Hospital we have already diagnosed more heartworm positive dogs than in the previous five years. Although there is no perfect test for cats, and we generally do not test cats for heartworm, we do recommend they be on heartworm prevention, even if they are strictly indoors. Mosquitos do not discriminate between indoors and out.
How is a heartworm test performed?
There are 2 ways to test for heartworm. The most common, and most accurate is an antigen test, which tests for adult heartworm. The second method, which is much less sensitive, is a microfilaria test, which essentially tests for the offspring of adult heartworms.
To test for heartworm using the antigen test, we need a small blood sample, usually 3-4 drops. The test generally takes 8-10 minutes to run, and then you will have the results.
Please make sure your pet is protected. Heartworm disease is deadly and so easily prevented.