by Association of Exotic Mammal Veterinarians: aemv.org

Many people have heard of heartworm disease in dogs, but not everyone is aware that pet cats and ferrets are also at risk of developing this potentially fatal disease.  Heartworm disease is caused by a parasitic worm (Dirofilaria immitis) that is transmitted via mosquito bites.  In brief, the mosquito bites an infected dog and ingests immature heartworms, called microfilaria. When the infected mosquito bites another dog, cat, or ferret the microfilaria are injected into the animal’s bloodstream.  The worms develop into larvae and migrate through the tissue into the blood stream, making their way to the heart where they mature and may reach lengths of up to 10 inches.

Ferrets have very small hearts and even a single adult worm can result in illness.  The worms not only interfere with the function of the heart, but small fragments may break off and travel through the blood stream to the lungs where they can cause serious lung disease.

All ferrets in “endemic” heartworm areas are potentially at risk. An endemic area is an area where the climate supports enough mosquitoes to keep the disease cycle going. Even ferrets kept indoors 100% of the time might encounter a mosquito inside the house.

Heartworm disease in ferrets is relatively uncommon, and can potentially be treated.  However, as heartworm disease can be serious or even fatal, owners should consider heartworm prevention medication, which is safe, effective and inexpensive.