When spring rolls around, many pet families begin to worry about fleas, ticks, intestinal parasites and heartworms. While I’m happy their pet’s health is on their mind, parasite prevention should be on the minds of pet families year-round. The parasites mentioned above and the diseases they carry can infect your dog or cat anytime of the year.
The Companion Animal Parasite Council (CAPC) recommends year-round parasite protection. In their 2025 Pet Parasite Forecast, CAPC reports that tick-borne diseases Lyme and anaplasmosis continue to expand into the American South and West, while the upper Midwest and Northeast continue to be high-risk areas. Ehrlichiosis, which is also spread by ticks, is still prevalent in the Southeast, though it’s expanding northward to the upper Midwest and New England regions.
The forecast also predicts that mosquitoes are increasingly spreading heartworm diseases throughout the Southeastern United States, with highest risks found along the Atlantic Coast and northward along the Mississippi River. Because of this northern spreading, there’s increased of heartworm from Kansas to Maryland, with several western states growing in risk as well, including New Mexico, Colorado, Wyoming, Montana, North Dakota, and Northern California.
Parasite prevention has improved dramatically since I became a veterinarian. We used to have powders, sprays and dips—all messy and bad smelling—that treated parasite infestations when they occurred, rather than preventing them. Parasite prevention today is light years better and is the topic of today’s blogpost.
A Road Map for Parasite Prevention
The first step in parasite prevention is consulting your veterinarian. As outlined above, parasites are not distributed evenly across geographic areas. Your veterinarian has the knowledge to advise you on what parasites need to be prevented in your pet. This is based not only on geography, but also on your pet’s lifestyle. Dogs that hike in the woods may need different preventatives than those that never leave their Manhattan apartment. Finally, your preference for administering oral medications or putting on a top-spot should be taken into consideration.
Choosing a Preventative
Instead of the powders, sprays and dips used in the past, we now have three major types of preventive medications: top-spot, oral medications and collars. Here’s where it gets complicated. There are lots of oral and top-spot parasite preventative options. Each one has a different drug, or combination of drugs, and each one has a different spectrum of anti-parasite activity. Most of my clients choose one product effective against the four main types of pet parasites: heartworms, fleas, tick and intestinal parasites.
Collars are generally the simplest. They work against ticks, and some may repel mosquitoes or have activity against baby fleas, also known as larvae.
Don’t Forget to Follow the Directions
One key point about parasite prevention is follow the directions!
Use cat medications on cats and dog medications on dogs. No swapping or pets can get really sick.
Each pet needs to take the medication as prescribed. Don’t use half a dose from your 60-pound Labrador for your 30-pound mini-doodle.
Give medications on schedule. Lapses leave your pet open to parasite infestations.
Discuss all potential side effects and health risks with your veterinarian. Not every medication is appropriate for your pet as some carry warning regarding pets with neurologic conditions. Others are not safe for small pets or very young pets.
For more information on pet parasite prevention, listen to a recent Ask the Vet Podcast where I interview a member of CAPC. Listen on Apple Podcasts, Spotify, or Amazon.