As winter fades and temperatures begin to rise, parasites become more than a nuisance—they become a serious health risk for dogs and cats. Spring marks the beginning of peak season for fleas, ticks, and mosquitoes, all of which can transmit dangerous diseases to pets.
March is the ideal time to review your pet’s parasite protection plan. At Applebrook Animal Hospital, we emphasize year-round parasite prevention as one of the most important steps you can take to protect your pet’s long-term health.
Why Parasite Prevention Matters in Early Spring
Many pet owners assume parasites are only a concern during the hottest months of the year. In reality, fleas, ticks, and heartworm-carrying mosquitoes become active as soon as temperatures rise above freezing. According to the Companion Animal Parasite Council, parasite risk increases significantly in the spring as temperatures rise and pets spend more time outdoors.
In our region, that means parasite exposure often begins as early as March.
Parasites Are More Than an Itch
Parasites can cause:
Skin infections and hair loss
Severe itching and discomfort
Anemia (especially in puppies and kittens)
Transmission of serious diseases
Life-threatening complications if left untreated
Some parasites can even spread illness to humans, making prevention important for the entire household.
Fleas: A Year-Round Threat for Dogs and Cats
Fleas are one of the most common external parasites affecting pets—and one of the hardest to eliminate once established.
Why Fleas Are So Persistent
Only about 5% of a flea infestation lives on your pet. The remaining fleas exist in the environment as eggs, larvae, and pupae. This makes infestations difficult to control without consistent prevention.
Common signs of fleas include:
Scratching or biting at the skin
Hair loss, especially over the tail base
Red, irritated skin
Visible flea dirt (black specks)
Cats are particularly sensitive to flea bites, and even a small exposure can trigger severe allergic reactions.
Ticks: Small Parasites with Serious Consequences
Ticks are active in wooded, grassy, and even suburban environments. They attach to pets while walking, hiking, or even spending time in the backyard.
Diseases Transmitted by Ticks
Ticks can transmit serious illnesses, including:
Lyme disease
Ehrlichiosis
Anaplasmosis
Rocky Mountain spotted fever
Many tick-borne diseases cause vague symptoms at first, such as lethargy, lameness, fever, or appetite changes, which may delay diagnosis.
Preventing tick bites is far safer—and far easier—than treating tick-borne disease after exposure.
Heartworm Disease: A Preventable but Dangerous Condition
Heartworm disease is caused by parasites transmitted through mosquito bites. Once infected, worms grow inside the heart and lungs, leading to permanent damage.
Why Heartworm Prevention Is Critical
Heartworm disease is much easier to prevent than treat
Treatment is costly and carries health risks
Cats are especially vulnerable, even with a single worm
There is no approved treatment for heartworms in cats
Because mosquitoes can appear early in spring, restarting prevention in March—or continuing it year-round—is essential.
Why Monthly Preventatives Work Best
Modern veterinary parasite preventatives are safe, effective, and easy to administer. Most products protect against multiple parasites at once, including:
Fleas
Ticks
Heartworms
Intestinal parasites
Consistent monthly prevention:
Breaks parasite life cycles
Protects your pet before exposure occurs
Reduces environmental contamination
Prevents future medical complications
Skipping doses—even during colder months—creates gaps in protection that parasites exploit.
Why Over-the-Counter Products Aren’t Enough
Many over-the-counter flea and tick products are ineffective or improperly applied, leading to continued infestations or adverse reactions.
Veterinary-recommended preventatives are:
Tested for safety and efficacy
Tailored to your pet’s weight, age, and species
Proven to offer reliable protection
Using the wrong product—especially in cats—can be dangerous. Always consult your veterinarian before starting any parasite prevention.
Parasite Prevention for Dogs vs. Cats
Although prevention is important for both, dogs and cats have different risks and requirements.
Dogs
Dogs are at higher risk for:
Tick exposure during walks and hikes
Heartworm disease
Intestinal parasites
Dogs benefit from broad-spectrum monthly prevention that covers external and internal parasites.
Cats
Cats—even indoor cats—are at risk for:
Fleas brought in on people or other pets
Heartworm disease from indoor mosquitoes
Severe allergic reactions to flea bites
Cats require species-specific products; dog preventatives should never be used on cats.
Spring Wellness Exams: The Best Time to Review Protection
March is an excellent time to schedule a spring wellness exam, allowing your veterinarian to:
Test for heartworm disease
Screen for intestinal parasites
Review current preventatives
Adjust protection as your pet ages or health changes
Wellness exams are a preventive measure that often detect hidden issues early—before they become more serious or costly.
Protecting Your Pet (and Family) This Spring
Parasite prevention is one of the simplest and most effective ways to protect your pet’s health. When started early and given consistently, monthly preventatives dramatically reduce the risk of disease, discomfort, and long-term complications. Some parasites even have Zoonotic potential which means people can catch them. Find out more about this from the CDC!
Spring should be a season of outdoor enjoyment—not itching, illness, or preventable medical problems.
Schedule a Preventive Care Visit Today
If you’re unsure whether your pet is fully protected, the team at Applebrook Animal Hospital is here to help. We can recommend the best parasite prevention plan based on your pet’s lifestyle, age, and health needs.
March is the perfect time to get ahead of parasite season and ensure your dog or cat is protected as spring approaches. Contact us today to schedule a wellness visit or refill your pet’s preventive medications.