Heartworm FAQS and Diagnosis

Heartworms are parasites that live in and around the hearts of dogs and cats. They can kill pets if not treated. Fortunately, there are simple heartworm prevention treatments available from your veterinarian. At Glastonbury Animal Hospital, we have been providing pet owners in Glastonbury, CT with heartworm prevention measures for many years. Following are the answers to several questions our veterinarian frequently receives regarding heartworms.


How Do Pets Get Heartworms?

Juvenile heartworms, called microfilaria, are transported from infected animals to healthy ones by mosquitoes. A mosquito bites a sick animal and sucks up some microfilaria. Microfilaria grow inside of the mosquito. The mosquito then flies to your pet and bites, releasing microfilaria into your pet’s bloodstream. The microfilaria travel to the heart, settle down and grow.

How Big Do Heartworms Get?

Heartworms can grow up to 14 inches long and an eighth of an inch wide. If left unchecked, heartworms will block your pet’s blood vessels, leading to severe illness and death.

How Long Do Heartworms Live?

Heartworms live up to five years. They grow slowly, so the first symptoms of heartworm disease are very mild. Often, by the time symptoms are apparent, the adults are large and can be difficult to kill.

What Are the Signs of Heartworms?

The first symptom is a low, persistent cough. Since this is also a sign of heart disease, any pet with such a cough needs a health exam to determine the cause. As heartworm disease progresses, the pet will be more tired than usual, have breathing problems, and may collapse after any exercise. Eventually, the limbs and abdomen swell, the pet loses appetite and, with that, weight. They will be listless. They then soon die.

How are Heartworms Diagnosed?

Our veterinarian will perform a blood test to check for heartworm juveniles and adults. It is recommended that these blood tests be performed as part of your pet’s usual wellness exams. If a pet shows signs of heartworms, then chest X-rays are done to look for the heartworms.

How are Heartworms Prevented?

Chewable heartworm prevention tablets can be given to your pet every month. Some kinds of tablets also help prevent fleas and ticks. This medication only kills microfilaria. Since it cannot kill adults, it is strongly recommended to get regular blood tests during your pet’s wellness exams.

Can I Stop Giving Medication When the Mosquito Season Ends?

It is recommended to give heartworm prevention medication year-round because microfilaria can live for long after cold weather sets in.

Schedule a Health Exam with Our Veterinarian for Heartworm Prevention in Glastonbury

Call Glastonbury Animal Hospital today at (860) 633-8394 for more information or to schedule an appointment with our veterinarian.



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