Heart worm disease, the parasite that travels in a dog’s blood and ultimately takes residence in the heart, is spread from dog to dog or canid to canid by mosquitos. Once relatively rare here in the Northeast, it is becoming quite the problem of late.
There is an upward trend here in the Northeast in cases of heart worm disease. While some of this is undoubtedly attributed to the movement of dogs from the South into the North via rescue groups, we must keep in mind that whatever the cause, it is very likely that the disease is present in our local canids (such as coyotes) which put our own dogs here at greater risk.
In days past, we used to recommend seasonal prevention for the disease. Give the heart worm meds from May through the first frost- October or November- no problem! However in recent years, I have moved away from this recommendation and into one of giving the medication year round. My thinking was swayed after a couple of these seasonal dogs contracted the disease, no doubt in the fall when everyone thought we were done with mosquitos.
While you may be safe when the snow is thick no the ground, I wish to point out that I did have a mosquito in my car in December a few years ago. Not to mention the times in January or February which allowed me to go jogging in a tank top. I have noticed that our winters here are getting a little milder and that spring seems to bloom a little quicker. Global warming or seasonal shift? I’ll let the climate experts decide.
I am no expert on mosquito life cycles, but to me the risk is not worth it. The added benefit of giving the medication year round is in better compliance- meaning, it is easier to get into the groove of once a month and staying there rather than remembering in time in the spring. I have seen, far too often, folks who remember to give their dog the first spring dose well into June or July, when the mosquitos have been out for quite some time.
Why should we care? Well, this particular nasty sets up shop in the heart and causes the heart itself to become deformed and have to work far too hard. In smaller dogs, the risk is so much greater. The treatment itself is expensive, painful, and involves almost 6 months of strict rest- no play time, no running, nothing but leash walks to go to the bathroom! That doesn’t sound like much fun for any dog.