Why year-round heartworm and tick prevention is so important
Heartworms, mosquitoes, and ticks are parasites, small critters that live on or inside another animal and feed off it. Parasites can make pets sick or uncomfortable. Untreated heartworm can block blood flow and become life-threatening. Ticks can carry diseases that affect your dog’s immune system and joints. That’s why it’s important for you to keep up your dog’s preventive care year-round and make sure all four seasons are safe for your pet.
While mosquitoes and ticks may be less active when it is cold outside, year-round parasite prevention is still necessary to protect your dog. Here’s why:
- Heartworm preventives work backward in time. They kill heartworm larvae (babies) picked up in the previous weeks. If you skip a month, any larvae your dog was exposed to during that gap may be allowed to mature into adult worms.
- Ticks are tougher than we think. Some species can be active on mild, cooler days, which means risk doesn’t disappear outside of the “traditional” summer season.
- Missed doses create gaps. It’s surprisingly easy to lose track of monthly treatments, especially during busy times of year or when routines change. Those gaps can leave dogs unprotected when mosquitoes or ticks are still active.
- Travel increases risk. Dogs who vacation with you or move to warmer areas may be exposed to mosquitoes and ticks that stay active all year, increasing their chance of infection.
- Climate patterns are changing. Shifting tick and mosquito ranges, influenced by climate change, are increasing the risk of insect‑carried disease in areas that used to see fewer cases.
- Many heartworm preventives protect against other parasites, too. By using them year‑round, you’re helping protect your dog—and your household—from a broader range of parasite risks.
Year‑round protection and routine screening go hand in hand
Leading experts agree:
- The Companion Animal Parasite Council recommends protecting pets from parasites year-round and advises routine screening to catch infections early, along with annual screening tests for diseases spread by ticks and mosquitoes.
- The American Heartworm Society recommends annual heartworm blood testing for all adult dogs, even those on monthly preventives. Regular testing helps make sure your pet is protected and helps catch any breakthrough infections.
These screenings are usually done during routine wellness visits, which makes it easier to build both prevention and screening into your dog’s regular care plan.
How do I choose the right pet parasite prevention for my dog?
There are many parasite prevention options, so you and your vet can discuss what works best for your dog.
- Oral medications: These monthly pills or chewables protect dogs against heartworms, ticks, fleas, mites, and some worms. Many dogs love getting their “treat” every month, but these products may not be good for picky eaters or dogs with food allergies.
- Topical medications: Monthly topical products protect against ticks and heartworms, as well as fleas, mites, and some intestinal parasites. Some also keep mosquitoes away. These are good for dogs who don’t like taking pills, but they may not work as well if they get washed off too soon. Some topical products for dogs are very toxic to cats, so be sure to check with your vet if you have a dog-and-cat household.
- Collars: Tick collars can protect against ticks and fleas for several months, but your dog must wear the collar all the time for it to work. They also don't protect against as many other parasites as other products do.
- Injectables: Some heartworm medications are given as a shot and last 6 to 12 months. This can be helpful if you have trouble remembering to give your dog their monthly preventive dose.
Using parasite prevention all year helps protect your dog from serious diseases spread by mosquitoes and ticks. It also helps keep your dog healthy. Ask your vet which products are best for your dog, and make sure your dog is tested every year for heartworms and tick-related diseases.
What are common pet parasite prevention misconceptions?
If your vet has recommended parasite prevention and routine testing for your dog, it’s perfectly normal to have questions. Below are some common concerns that pet parents may have, along with helpful answers from professionals to guide you.
“My dog mostly stays indoors.”
Mosquitoes and ticks can easily find their way inside, so even dogs that stay indoors can be exposed and get sick.
“We don’t hike or live near the woods.”
Mosquitoes and ticks aren’t only found in the countryside. They can also live in cities and neighborhoods. Things like warmer weather, standing water, and growing cities help them survive in these areas.
“I remove all ticks from my dog immediately after our walks.”
Some ticks are very tiny, and they can be easy to miss, especially if your dog has a thick coat.
“We don’t live in an area that has mosquitoes or ticks.”
While areas with a warm, moist climate have more mosquitoes, these pesky parasites are found across the U.S. Tick-borne diseases have been reported in every state. The CAPC provides local forecasts to help pet parents understand the current risk in their area.
“Pet parasite prevention is too expensive.”
Providing year-round parasite prevention benefits your pet more upfront than treating your dog for heartworm disease or a tick-borne illness down the line.
Final thoughts: Make year‑round protection part of your dog’s routine
Staying on schedule with prevention and regular testing is one of the most effective ways to protect your dog’s health. Year‑round heartworm and tick protection closes the gaps that changing seasons, travel, and busy routines can create, while annual blood tests give your vet a chance to catch diseases early, often before you see any signs at home.
Frequently asked questions
Frequently asked questions about this topic
Prices can vary from medication type to procedure. Ultimately, paying for year-round preventive care—such as chewables or flea and tick collars—typically costs less than veterinary treatment of heartworm and Lyme disease.
Your veterinarian will typically recommend testing before starting or restarting heartworm prevention because if your dog is already infected, the medication can cause a dangerous reaction. Always check with your vet before starting or restarting heartworm prevention. While heartworm prevention medications are used as part of the treatment of the disease, a vet must closely watch the process to keep your dog safe.
Yes. All dogs, including those who were previously successfully treated for heartworm disease, are at risk of infection.
Yes. If your dog tests positive and they aren’t showing signs, your vet will decide if they need treatment or further testing.
No. You can’t get Lyme disease directly from your dog. But if your dog had an infected tick, you may have been exposed to one too.
