Heartworm Disease in Dogs & Cats | Apopka, FL
Heartworm disease is a serious, life-threatening parasitic infection spread by mosquitoes — and in Florida, the risk is present every single month of the year. At Pet Xpert Animal Clinic in Apopka, FL, we test for heartworm disease using our in-house laboratory and provide comprehensive guidance on treatment and prevention. If you’re concerned about your pet or need to start a prevention protocol, call (407) 886-7387 today.
Understanding Heartworm Disease in Florida Pets
Heartworm disease is caused by a parasitic roundworm (Dirofilaria immitis) that lives in the heart and pulmonary arteries of infected dogs and, less commonly, cats. Transmission occurs exclusively through mosquito bites — an infected mosquito deposits larvae under the skin, and the larvae migrate over several months to the heart. Adult heartworms can reach 6–12 inches in length and, in heavy infections, can number in the dozens in a single dog.
In dogs, heartworm disease progresses through four stages. Early stages may show no symptoms, while advanced cases cause coughing, exercise intolerance, fatigue, weight loss, and ultimately heart failure. Diagnosis requires a blood antigen test along with assessment via chest X-rays and EKG to evaluate cardiac involvement. Treatment involves an injection protocol to kill adult worms along with strict exercise restriction — a serious and stressful process for pets and owners alike. Prevention is always far preferable to treatment.
In cats, heartworm disease is different and no approved treatment exists. Prevention is the only reliable protection. Learn more about year-round heartworm prevention options available at our clinic.
Heartworm Disease FAQs
How does a pet get heartworm disease?
Heartworm is transmitted solely through the bite of an infected mosquito. The mosquito picks up immature heartworm larvae (microfilariae) while feeding on an infected animal, and transmits them to the next animal it bites. Heartworm cannot be passed directly from pet to pet — mosquitoes are the only vector.
What are the symptoms of heartworm disease in dogs?
Early-stage infections often cause no visible symptoms. As the disease progresses, signs include a soft, persistent cough, reluctance to exercise, fatigue after mild activity, decreased appetite, and weight loss. Advanced heartworm disease can cause difficulty breathing, a swollen abdomen (from fluid accumulation), and heart failure.
How is heartworm disease diagnosed?
Diagnosis begins with a blood antigen test that detects proteins from adult female heartworms. A positive test is typically confirmed with additional testing. Chest X-rays evaluate heart and lung changes, and an EKG assesses cardiac function. The results help Dr. Alex determine the severity of infection and the safest treatment approach.
Can heartworm disease be treated in dogs?
Yes, but treatment is involved, expensive, and carries risks. Treatment involves a series of deep muscle injections to kill adult heartworms, combined with strict exercise restriction for several weeks to prevent complications from dying worms. The best approach is prevention — monthly preventatives are safe, affordable, and highly effective. Annual testing verifies prevention is working.
Is heartworm disease dangerous for cats?
Yes — and unlike dogs, there is no approved treatment for heartworm in cats. The disease can cause severe respiratory distress, sudden collapse, and death. Prevention with a cat-specific heartworm preventative is the only reliable protection. We strongly recommend year-round prevention for all cats in Florida.
How do I know if my pet’s heartworm prevention is working?
Annual heartworm testing is the only way to verify that prevention has been effective. No preventative is 100% effective if doses are missed or vomited, and new resistance patterns are being monitored in some regions. Testing annually — even for pets on continuous prevention — is the standard of care recommended by the American Heartworm Society.
How much does heartworm treatment cost compared to prevention?
Prevention costs a small fraction of treatment. Monthly heartworm preventatives for dogs range from roughly $6–$15 per month depending on the product and the dog’s size. Heartworm treatment can cost hundreds to over a thousand dollars and involves weeks of activity restriction and monitoring. Prevention is the clear, cost-effective choice for every pet owner in Florida.