Category Archives: heartworm

Heartworm Disease

Spring is in the air! The weather is getting warmer and we are starting to head towards those summer months. With the warmer weather comes the flowers blooming, pools being opened, longer days outside, summer vacations, and also those annoying bugs come back from hiding away for the winter. Mosquitos are one of those bugs. Possibly even the most annoying of the insects to come out in the warmer months. April is National Heartworm Prevention Month, so this blog is to inform you of all of the basics of Heartworm in dogs and cats. Many people still only think that heartworm is a concern in the southern U.S. which sadly is incorrect. Heartworm is found in all 50 states and that is why EVERYONE that owns furry friends should be knowledgeable about the basics of heartworm disease.

Heartworm disease is a serious and even fatal disease that can affect dogs and cats. This disease is caused by worms that infect the blood and live in the heart, lungs and blood vessels. This infection can cause heart failure, lung disease and cause other organs in the body to be compromised.

Heartworm disease is transmitted by mosquito bites. Mosquitos get infected by biting animals that have been infected with heartworm and currently have the baby worms or microfilaria living in their blood stream. When that infected mosquito bites another non infected animal the baby worms enter that animal by the bite wound.

The life cycle of heartworms simplified: Mosquito bites infected animal. Baby worms that are now in the mosquito develop into infective larvae stage over 10-14 days. Infected mosquito bites non-infected animal. Larvae are transmitted to non-infected animal through mosquito bite wound. The larvae then live in the tissues for around 2 months while developing. The adult worm is now living in bloodstream and heart for the next 4-5 months while it reaches full maturity. Mature worms now live in heart and bloodstream and can start producing larvae that can now infect another mosquito. Mosquito bites the now infected animal and the life cycle repeats.

Heartworms can live for 5-7 years in dog and 2-3 years in cats. Once an animal is infected with heartworm it can take months for symptoms to appear.

heartworm disease
Canine symptoms you may see could be the following:


    • mild persistent cough


    • reluctance to exercise


    • fatigue after mild activity


    • decreased appetite


    • weight loss


    • swollen abdomen(extra fluid)-severe cases


    • caval syndrome-blockage of blood flow-severe cases



heartworm disease
Feline symptoms may include:


    • coughing


    • asthma-like attacks


    • periodic vomiting


    • loss of appetite


    • weight loss


    • difficulty walking/fainting


    • fluid accumulation in abdomen



Diagnosis is made by a blood test looking for heartworm proteins. Cats are harder to diagnose and usually require a special blood test and even ultrasound/x-rays.

While it is true that the southern states are more known for heartworm infections solely because the temperature is warmer longer periods of the year. Warm weather = mosquitos. Heartworm disease has been diagnosed in every state of the US. The incidence for heartworm has grown dramatically in the last 5-10 years.

Current recommendations is year round heartworm prevention for all dogs and cats in all states. There are many options for preventives. The ones that we use at AHDC are-Heartgard (dog), Interceptor (dog), and Revolution (cats/dogs). These preventives also protect against certain intestinal parasites. Revolution also protects against fleas, and some ticks in dogs.

Testing should be done for heartworm disease every year, or before restarting prevention if a dose was missed. Even if your pet is on a preventative year round, testing should still be done to be sure of product effectiveness of prevention. Testing can be done at the vet office with a small amount of blood and results are available in as little as ten minutes! Some of the companies that sell preventatives will pay for all or a portion of treatment cost if proven that animal is on year-long prevention with no missed doses and has yearly testing documented in their medical records. Some of the medications can be harmful to animals that have active heartworm infections, which is why testing is required if doses are missed.

Treatment for heartworm is very expensive and required to prevent death from large worm burdens. Sadly there is no treatment approved in cats-the only way is prevention! Treatment can range in cost from $1200-$2000, and includes bloodwork, x-rays, multiple injections, oral medications, and many, many vet visits. When comparing cost of treatment vs cost of prevention there should be no question! Prevention is usually less than $300 for a whole year of protection. Prevention is the way to go!

As you can see it’s a little difficult to condense all the information of heartworm disease into a short blog, but all the information is extremely important and we want everyone to be fully educated! If interested in more information on preventions we have available, please contact our office to help your pet be the healthiest they can be!

Mosquito Transmitted Diseases

If you’ve been keeping up with the news, you’ve probably been hearing a lot about Zika virus, a disease that is transmitted by mosquitoes and can make us ill. But did you know that mosquitoes carry diseases that can cause illness in our pets? Most pet owners are aware of diseases like rabies, feline leukemia, and canine kennel cough. These diseases are transmitted to our pets by contact with other cats, dogs or sometimes wildlife. Heartworm disease is an infection that can be transmitted to our dogs and cats by the bite of an infected mosquito. That means that our pets do not need to be around other animals to become infected with heartworm disease.

Luckily for pet owners, heartworm disease can be very easy to prevent. There is a variety of monthly medications that can be prescribed to your dog and cat, including flavored chewable tablets and topical medications.

Heartworm disease has been on the rise in Pennsylvania over the past few years. According to the American Heartworm Society, vet clinics in PA were reporting an average of 1-5 heartworm cases per year in 2010. Some clinics in northern PA were seeing even less than that. Then in 2013, at the next report, all surveyed clinics were reporting at least 1-5 cases per year, and many clinics reported 6-25 cases per year. This does not include the millions of pets who are never tested.

Heartworm disease affects dogs and cats in different ways. The heartworm larvae is injected into the bloodstream by the mosquito. In dogs, the larvae grow into adult worms in the heart and lung vessels, causing severe damage that may be permanent. There can be as many as 50 adult worms in the heart and lungs in an infected dog. Symptoms in dogs can range from a mild cough to full blown heart failure. Sometimes there are no symptoms at all! In cats, the worm burden tends to be much less but they are more sensitive to the larvae. The larvae can trigger a severe inflammatory reaction in the lungs similar to asthma. This inflammation can cause fatal respiratory disease.

Once infected, heartworm disease can be painful and expensive to treat. There is an injection for dogs that is given multiple times over the course of 1 month to kill the adult heartworms. There is no specific treatment for cats, only supportive care.

It is recommended to test for heartworm disease yearly, even if your dog is on year round prevention. This helps to ensure that the prevention is working. The test also checks for other diseases like Lyme disease. Reliable testing is not available for cats and they can be given heartworm preventive without testing. It is recommended to test your dog before starting the preventive. The preventives only kill the larvae that have been transmitted to your dog within the past 30 days. For example, if your dog was bitten by an infected mosquito on May 15th and you started your preventive on July 1st, your dog is NOT protected from heartworm disease. You should test again in 6-12 months to check for a mature infection. This is another advantage to giving heartworm prevention year round; the risk of missing an infection is much less. And with winters getting warmer, how do we know when the last mosquito left Pennsylvania? September? December? Or did they ever leave at all?

For more information about canine and feline heartworm disease, talk to your vet or visit the American Heartworm Society’s website at www.heartwormsociety.org.

Heartworm Information

If you’ve been keeping up with the news, you’ve probably been hearing a lot about Zika virus, a disease that is transmitted by mosquitoes and can make us ill. But did you know that mosquitoes carry diseases that can cause illness in our pets? Most pet owners are aware of diseases like rabies, feline leukemia, and canine kennel cough. These diseases are transmitted to our pets by contact with other cats, dogs or sometimes wildlife. Heartworm disease is an infection that can be transmitted to our dogs and cats by the bite of an infected mosquito. That means that our pets do not need to be around other animals to become infected with heartworm disease.

Luckily for pet owners, heartworm disease can be very easy to prevent. There is a variety of monthly medications that can be prescribed to your dog and cat, including flavored chewable tablets and topical medications.

Heartworm disease has been on the rise in Pennsylvania over the past few years. According to the American Heartworm Society, vet clinics in PA were reporting an average of 1-5 heartworm cases per year in 2010. Some clinics in northern PA were seeing even less than that. Then in 2013, at the next report, all surveyed clinics were reporting at least 1-5 cases per year, and many clinics reported 6-25 cases per year. This does not include the millions of pets who are never tested.

Heartworm disease affects dogs and cats in different ways. The heartworm larvae is injected into the bloodstream by the mosquito. In dogs, the larvae grow into adult worms in the heart and lung vessels, causing severe damage that may be permanent. There can be as many as 50 adult worms in the heart and lungs in an infected dog. Symptoms in dogs can range from a mild cough to full blown heart failure. Sometimes there are no symptoms at all! In cats, the worm burden tends to be much less but they are more sensitive to the larvae. The larvae can trigger a severe inflammatory reaction in the lungs similar to asthma. This inflammation can cause fatal respiratory disease.

Once infected, heartworm disease can be painful and expensive to treat. There is an injection for dogs that is given multiple times over the course of 1 month to kill the adult heartworms. There is no specific treatment for cats, only supportive care.

It is recommended to test for heartworm disease yearly, even if your dog is on year round prevention. This helps to ensure that the prevention is working. The test also checks for other diseases like Lyme disease. Reliable testing is not available for cats and they can be given heartworm preventive without testing. It is recommended to test your dog before starting the preventive. The preventives only kill the larvae that have been transmitted to your dog within the past 30 days. For example, if your dog was bitten by an infected mosquito on May 15th and you started your preventive on July 1st, your dog is NOT protected from heartworm disease. You should test again in 6-12 months to check for a mature infection. This is another advantage to giving heartworm prevention year round; the risk of missing an infection is much less. And with winters getting warmer, how do we know when the last mosquito left Pennsylvania? September? December? Or did they ever leave at all?

For more information about canine and feline heartworm disease, talk to your vet or visit the American Heartworm Society’s website at www.heartwormsociety.org.

What Is Heartworm Disease?

Heartworm disease is a serious and potentially fatal condition caused by parasitic worms living in the arteries of the lungs and occasionally in the right side of the heart of dogs, cats and other species of mammals, including wolves, foxes, ferrets, sea lions and (in rare instances) humans. Heartworms are classified as nematodes (roundworms) and are filarids, one of many species of roundworms. Dogs and cats of any age or breed are susceptible to infection.