Each year I have the heartbreaking task of informing dog owners that their beloved pet has a crushing condition. What is even worse, it is a condition that could have been prevented. April is Heartworm Disease Awareness month. Heartworm disease (HWD) can be fatal and is devastating for both the pet and the owners. Heartworms are quite literally worms that live in the heart, and are transmitted by mosquitos, which are of course ubiquitous in most of the country. In more temperate areas like here in FL, the mosquitos are present year-round, so protection must be a priority during all months. Despite the many effective products we have available, the incidence of infection continues to increase (see incidence maps at https://www.heartwormsociety.org/veterinary-resources/practice-tools/incidence-maps ), with the highest concentration of cases along the Southern Atlantic and Mississippi River areas.

Dogs are the natural host for heartworms. This means that the worm larvae  can be injected into the dog’s bloodstream by the mosquito and complete a full life cycle, which include reproduction so another mosquito can ingest worm larvae when they feed and then infect another dog. That is a bit simplistic, so if you are interested in more details, please see https://www.heartwormsociety.org/images/pdf/AHS2014HWLifeCycleCLIENTBW.pdf

The cost of treatment for HWD is high, several hundred dollars. A year’s worth of preventative is a small fraction of the cost of treatment. Treatment for HWD is not only expensive, but is also very difficult on the dog. The treatment takes months to complete, and during that time the pet must be under strict exercise restriction to minimize the risk of side effects including death. That is much easier said than done for an energetic pup. And even after treatment, there may still be lasting damage to the heart.

While dogs are the pets we most commonly associate with HWD, we also need to protect our cats and ferrets. Cats and ferrets are not natural hosts, so a complete life cycle will not occur, but can still suffer severe illness, including death. Often, HWD in cats presents as heartworm associated respiratory distress syndrome, which is frequently confused with asthma. The first symptom commonly seen though, is unfortunately sudden death from an anaphylactic reaction. At present, there is no approved treatment for cats or ferrets fighting HWD. Unfortunately, just because your pet might be a  strictly indoor pet, it is still at risk of HWD since there is no way to ensure that a mosquito never enters your home.

Again, the best way to protect your pet is with consistent use of a product to prevent HWD. There are many options out there, so it is understandable that it might seem overwhelming to choose. Not all options are appropriate for every pet, and there is quite a bit of misinformation available on the web. Talk to your vet about which product can best fit you and your pet’s needs. If it’s been a while since your pet has had a heartworm test or hasn’t been on prevention, please schedule a test and let’s get her protected!

In honor of Heartworm Disease Awareness Month, Young’s Animal Hospital is having a raffle for a cat goodie basket and a dog goodie basket. All dog and cat clients who visit us will be entered to win!

Angela Bockelman, DVM, PhD