Heartworm Disease Testing and Prevention in Monona and Madison
Heartworm disease is a serious, potentially fatal illness spread by mosquitoes, and Wisconsin’s lakes and wetlands give mosquitoes plenty of places to breed each summer. At Four Lakes Veterinary Clinic, we test dogs for heartworm every year, recommend the right prevention for both dogs and cats, and guide families through treatment if their pet tests positive.
What Is Heartworm Disease?
Heartworms are long, thin parasites that live in the heart, lungs, and nearby blood vessels of infected animals. When a mosquito bites an infected animal, it picks up tiny immature worms and passes them to the next pet it bites. Over about six months, those larvae grow into adult worms that can reach up to a foot long. Left untreated, heartworms damage the heart and lungs and can lead to heart failure. Dogs are a natural host, while cats are atypical hosts, but even a few worms can cause serious respiratory disease in cats.
Signs of Heartworm Disease
Early heartworm infection usually causes no visible signs, which is why yearly testing matters. As the disease progresses, dogs may show:
- A mild, persistent cough
- Tiring easily during walks or play
- Decreased appetite and weight loss
- A swollen belly from fluid buildup
- Difficulty breathing or collapse in advanced cases
In cats, signs can include coughing, asthma-like breathing, vomiting, or sudden collapse. If your pet has any of these symptoms, schedule a sick pet visit right away.
How We Test for Heartworm
We recommend a heartworm test for every dog once a year, usually during their wellness exam. A small blood sample processed through our in-house laboratory testing can screen for heartworm along with tick-borne diseases like Lyme disease. Testing before starting or restarting prevention is important, because giving preventatives to an infected dog can cause complications. Diagnosing heartworm in cats is more involved and may require additional blood tests, x-rays, or an ultrasound.
Heartworm Treatment
Treatment for dogs follows guidelines from the American Heartworm Society and typically includes medications to weaken the worms, a series of injections to eliminate adult heartworms, and several weeks of strict rest to reduce the risk of complications. Your veterinarian will stage the disease first with bloodwork and imaging. There is no approved medication to kill adult heartworms in cats, so feline care focuses on managing symptoms and supporting the lungs, which makes prevention especially important.
Simple, Affordable Heartworm Prevention
Preventing heartworm is far safer and less expensive than treating it. We recommend year-round prevention for dogs and cats, including indoor cats, because mosquitoes easily find their way inside. Options include monthly chewables, topical products, and longer-lasting injections. You can pick up preventatives at our pharmacy, order them through our online store, and check our current promotions for instant rebates on products like Heartgard PLUS and combination flea, tick, and heartworm medications. Keeping up with annual visits and vaccines through our Free Vaccines for Life program makes it easy to stay on schedule. Explore other common illnesses on our conditions page.
Heartworm Disease FAQs
How do pets get heartworm disease?
Pets get heartworm disease from the bite of an infected mosquito. Heartworm is not spread directly from one pet to another.
Does my dog need a heartworm test every year?
Yes. Annual testing confirms your dog’s prevention is working and catches infections early, even for dogs that take preventatives year-round, since a missed or late dose can leave a gap in protection.
Do indoor cats need heartworm prevention?
Yes. Mosquitoes get indoors easily, and studies show indoor cats are diagnosed with heartworm too. Because there is no approved treatment for heartworm in cats, prevention is the best protection.
Is heartworm prevention needed year-round in Wisconsin?
We recommend year-round prevention. Wisconsin weather can change quickly, and many monthly heartworm products also protect against intestinal parasites that are active all year.
What happens if my dog tests positive for heartworm?
Your veterinarian will run additional tests to stage the disease and build a treatment plan that follows American Heartworm Society guidelines, including medications, injections, and a period of strict exercise restriction.
Can heartworm disease be fatal?
Yes. Untreated heartworm disease can cause lasting damage to the heart and lungs and may be fatal. Early detection and consistent prevention greatly reduce that risk.
What heartworm prevention options do you offer?
We offer monthly chewables, topical treatments, combination flea, tick, and heartworm products, and longer-lasting injectable options. Your veterinarian will recommend the best fit for your pet.
Keep Your Pet Protected From Heartworms
It is easy to test, protect, and stay on track with heartworm prevention. Call Four Lakes Veterinary Clinic at (608) 819-6750 to schedule your pet’s heartworm test in Monona and Madison.