Learn more about heartworm and how you can protect your pets from this potentially fatal disease below.
Heartworm Testing and Prevention
At the Animal Hospital of Tiffin, we want to make sure our clients are thoroughly informed about this potentially deadly disease. Below are some common FAQs that might help answer any questions or concerns about heartworm disease. Please feel free to call us at 419-455-0470 for any other concerns you might have about your pet.
What is heartworm disease?
Heartworm disease is caused by foot-long worms (Dirofilaria immitis). It’s a serious and potentially fatal disease in pets in the United States and many other parts of the world.
Heartworm lives in the:
- Blood vessels
- Severe lung disease
- Heart failure
- Damage to other organs
Heartworm disease affects:
Because wild species such as foxes and coyotes live in proximity to many urban areas, they are considered important carriers of the disease.
How is heartworm disease transmitted?
It all comes down to the mosquito!
Let us explain:
Adult female heartworms living in an infected animal produce microscopic baby worms called microfilaria that circulate in the bloodstream. When a mosquito bites and takes a blood meal from an infected animal, it picks up these baby worms, which develop and mature into “infective stage” larvae over a period of 10 to 14 days. Then, when the infected mosquito bites another dog, cat, or susceptible wild animal, the infective larvae are deposited onto the surface of the animal’s skin and enter the new host through the mosquito’s bite wound. Once inside a new host, it takes approximately 6 months for the larvae to mature into adult heartworms. Once mature, heartworms can live for 5 to 7 years in dogs and up to 2 or 3 years in cats. Because of the longevity of these worms, each mosquito season can lead to an increasing number of worms in an infected pet.
What are the stages/signs of heartworm disease?
Stage 1: Typically symptom-free. In this stage, the heartworms are present and settle into the heart. However, in stage one the disease has not yet progressed to the point where the heartworms will have produced a new generation of microfilariae, and the dog’s body will not yet have produced antigens in an amount sufficient for detection.
Stage 2: Moderate symptoms including intolerance for exercise and a more lingering cough. The heartworms have been present long enough in the body for antibody production and probable microfilariae production. During this phase, heartworm disease may be detected with blood tests.
Stage 3: Very noticeable and have a big impact on your dog’s health. Dogs continue to cough and experience fatigue after exercise, may be reluctant to exercise at all, and can have trouble breathing. During this stage, dogs may also cough up blood. By stage three, the disease is quite evident on x-rays. The worms in the heart and large vessels will be obvious on x-rays.
Stage 4: Very visible heartworm disease symptoms. These symptoms are accompanied by long-term implications for the dog’s health. These dogs are very ill. The symptoms are similar to Stage 3 but more severe. Dogs will be reluctant to exercise, tired after exercising, and will exhibit a cough. They will probably experience trouble breathing as well. Testing may reveal the impact of the disease in the form of abnormal sounds within the dog’s heart and lungs and an enlarged liver. Even with treatment, this stage of the disease carries a high risk of long-term debilitation and possible death.
Why do we recommend testing if my dog is already on prevention?
Annual testing is necessary, even when dogs are on heartworm prevention year-round. In some cases, there could be resistance.
Annual testing ensures:
- The prevention program is working. If you don’t test, you don’t know to treat.
- Heartworm medications are highly effective at prevention, but not 100% effective.
- If one dose is missed, it leaves them unprotected.
If the dog has been OFF prevention for 2 months or longer, then re-testing (3 tests) will need to be performed:
1st test: At that time
2nd test: Again in 6 months
3rd test: Again on the one-year anniversary date of the initial test
After all 3 tests are completed then test annually.
*Important* Giving heartworm preventatives to a heartworm-positive dog can cause adverse reactions and could be fatal. This is why we require an up-to-date heartworm test in order to purchase prevention.
How do we test for heartworm disease?
Blood Parasite Screen 4Dx Plus Idexx Snap Test also known as ‘the heartworm test’, efficiently this test for heartworm disease and tick-transmitted pathogens. Test annually to help prevent the spread of:
- Heartworm (spread by mosquitoes)
- Ehrlichiosis (spread by ticks)
- Lyme disease (spread by ticks)
- Anaplasmosis (spread by ticks)
For more info on ticks, click here.
Why do we recommend year-round heartworm prevention?
Because the life cycle of the heartworm is so long, it takes several months for a larva to become an adult heartworm. If your dog is infected late in the fall and is taken off of heartworm prevention over the winter, there is a high likelihood of developing the disease. Prevention can be purchased oftentimes for less than $16 per month whereas treating a case of heartworm disease can cost $1500-$3000.
With monthly preventions, each product prevents some intestinal parasites.
What types of prevention are available?
Injection is a Vet-Administered injection under the skin.
If you have a hard time remembering to give the monthly prevention, we have great news! We offer ProHeart 6.
ProHeart 6 (moxidectin) – Is the Only Vet-Administered injection to prevent heartworm disease in dogs 6 months of age and older for 6 FULL months.
ProHeart 6 also treats common hookworm infections your dog may have at the time of injection.
Topical is a prescription solution that is administered on the skin monthly.
For dogs apply on the back of the neck/shoulder blades.
For cats apply at the back of the head where they are less likely to reach with licking.
Advantage Multi (imidacloprid/moxidectin) –. Treats and controls heartworm disease, roundworms, hookworms, and whipworms. This product also kills and prevents fleas and sarcoptic mange.
Revolution (selamectin) – Treats and protects dogs against fleas, American dog tick, ear mites, heartworm disease, and sarcoptic mites.
Treat and protects cats against fleas, ear mites, heartworm disease, roundworms, and hookworms.
Oral is a prescription medication given by mouth each month.
Heartgard Plus (ivermectin/pyrantel) – A beef-flavored chewable that is given monthly. Also treats and controls roundworms and hookworms.
Interceptor Plus (milbemycin oxime/praziquantel) – A chicken-flavored chewable that is given monthly. Also treats and controls roundworms, hookworms, whipworms, and tapeworms.
Simparica Trio (sarolaner/moxidectin/pyrantel) – A liver-flavored chewable tablet that is given monthly. Also treats and controls roundworms, hookworms, fleas, and five types of ticks.
We can talk to you about your preferences and your pet’s lifestyle to choose the best product for you. Look for rebates and sales on our Online Pharmacy.