Heartworm Disease - Vet Around Town

Heartworm Disease: Kind of a Big Deal!

July 12, 2017 Jenna Scibilia, VMD

Over two years ago when I moved to Texas from Massachusetts, I knew that many things would be different. I readily acclimated to the tacos, BBQ, and lake life, but what continues to amaze me is the number of ways that Texas tries to hurt us! Between the snakes, scorpions, stifling hot summers, and I-35, it's a wonder that any of us are still standing!

With our warm climate, Texas is a hotbed (literally) for many infectious diseases. Now one of the saddest things I've seen since being a veterinarian in Central Texas is the huge number of dogs infected with heartworms. It's so important that every pet owner in the country (and especially in the Southern states) is aware of heartworm disease and its seriousness. This is a preventable disease!

Despite the fact that we have easily obtainable, relatively affordable, and effective medications to prevent the development of heartworms in dogs and cats, heartworm disease continues to be on the rise in this country. Below is the predicted incidence of heartworm disease for 2017, from the Companion Animal Parasite Council. Come on Texas, we can do better than that!

How do pets get infected with heartworms?

Heartworms use mosquitos as their little minions. Simply put, the mosquito will feed on an infected animal and pick up baby heartworms (microfilaria), which will then mature into a larval stage that can then be spread to another animal while the mosquito is feeding. Click here to see a video of a microfilaria that we saw this month in a drop of one dog's blood. Ew!

As you know, mosquitos are here in Austin year-round. Have you ever been bitten by a mosquito while inside a house? I'm pretty sure we all have! Because mosquitos are sneaky, they won't hesitate to come inside uninvited and can infect your indoor cat! This is why we recommend continuous monthly heartworm prevention in all dogs and cats.

As stated by the American Heartworm Society, "it is possible for an animal to become infected by missing or delayed administration of just one dose of preventive, particularly in highly endemic areas." I'm looking at you, Texas! Set as many alarms, alerts, and reminders as needed to give that prevention on time every month!

What does heartworm treatment entail?

For cats, there is currently no safe treatment for heartworm disease. Even one worm can cause severe damage to the heart and lungs; this is why prevention is key.

For dogs, the safest and most effective protocol has been published by the American Heartworm Society. It consists of premedication with antibiotics to weaken the worms, an approved monthly preventative to kill the immature larval stages, and then a series of three injections of a medication that kills the adult worms. Dogs must be strictly crate rested throughout treatment and for one month after the final injection of adulticide. If allowed too much activity, worms that are dying off can become clogged in the vessels within the lungs, potentially leading to respiratory distress, heart failure, and even sudden death. The treatment is long (three months minimum), expensive (typically $500 - 1500), and risky (like I said, sudden death is possible). Now doesn't it seem easier to stick with prevention rather than risk infection?

Earlier this year I followed this protocol for my first foster dog with South Texas Aussie Rescue. Can you believe that this beautiful, happy, cuddly dog had a heart full of worms? Here I am, applying an ice pack to his injection site after treatment, while he soaked up some snuggles. Ouch!

How do I keep my pet safe from heartworms?

It's easy: give a monthly heartworm preventative. On time. Every month.

You will need to have your pet tested for heartworm disease every year. There is always a small chance that your pet may become infected despite appropriate preventative administration. In this case, we will want to know as soon as possible so that we can minimize the damage done by the worms.

I should note the importance of obtaining your preventatives from a trusted source. If you get them from your veterinarian, the manufacturer will guarantee the product and will often pay for your pet's treatment if infection occurs despite proper administration of their product. Our online pharmacy carries this guarantee. If you get the preventatives from an outside source, the manufacturer will not guarantee the product. See the FDA's recent warning against purchasing pet medications from unreliable sites.

For much, much, much more information about heartworm disease, please check out the website of the American Heartworm Society. Do not hestitate to contact me or comment below with any questions regarding heartworms, prevention, or treatment.

Is your pet due for a heartworm test? Do you need preventatives? Do not leave your pet unprotected! Contact us to schedule an appointment!