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Here it is - my inaugural blog. The lovely Lisa, our clinic’s media guru, has gently and persistently urged me to start blogging. Truthfully, she has urged us all. I am going to take the plunge with a fairly mild but relevant topic: bug bites.

Spring has definitely sprung now in beautiful

Northumberland County, and with it, an active insect population buzzing, flitting and crawling about. We spend a lot of time now discussing ticks, however, there are other bugs that perennially make our (and our pets) outdoor fun, well, less fun.

Firmly in the category of ‘not fun’: Black flies. I will admit, I didn’t fully appreciate black flies until I moved to Northumberland County. They are so tiny - like innocuous fruit flies I first thought. Furthermore, black flies don’t buzz or whine in your ear like a mosquito. And perhaps most nefariously, you never feel their bites until about 8 hours later for some reason. But man! I hate black fly bites! For a tiny critter, they leave a welt sometimes the size of a loonie! There is that little blister in the centre… and they always get you right behind the ears… Last weekend I lathered a ton of insect repellent... BEHIND my ears… but one of the critters bit me inside the ear instead. Dang.

Black flies bite dogs too. I think they bite anything with blood, actually. I suspect they bite cats, but cannot say for certain I have seen a black fly bite on a cat (I think they would definitely pick the ears). Black flies really seem to like to bite dogs on their soft little underbellies, especially between their hind legs. There is less fur covering this area, and the skin is a little thinner, likely giving the nasty critters easier access to their meal. The black fly bites on doggy tummies often look like bulls-eyes. They can just be a very discreet red circle on the first day, but then they often fade a little and look like a red ring with a dot in the middle by day two. This causes a lot of alarm for some of us, because we have been taught that in PEOPLE (not dogs) that a “bulls-eye rash” is a sign of Lyme infection.

I will admit to you, I have never found pictures of black fly bites in any veterinary textbook. I remember no class on Black-Fly bites in vet school. Likewise, I have attended numerous dermatology lectures over the years, and never once has anyone discussed black fly bites - but I think they should! As these bites can look very alarming.

If there are a lot of bites - it can look quite terrible - like a whole bunch of bruises. In my experience, they do look worse on small dogs with pale, thin, skin (eg. yorkies). I must sheepishly admit, as a freshly minted veterinarian, I mistook a dog with a tummy covered in black fly bites for a more serious clotting disorder. As such, I understand why people look at them with great alarm.

This week, I saw a little dog tummy with a few good black fly bites & snapped a picture. The bites were already likely 3-5 days old, and had faded a bit. And this, is what inspired my first blog. Maybe the next person who doctor-google’s “bulls-eye rash dog belly” will stumble upon this post and take a big sigh of relief. Who knows, maybe it will be an enthusiastic young veterinary colleague about to run a coagulation profile. Enjoy the great Ontario spring weather!

Dr. Karen McKenzie

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