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The hot summer months and humidity bring with it mosquitoes which can transmit many diseases to pets and humans. Heartworm disease is prevalent in dogs and to a lesser extent cats and ferrets. Mosquitoes feed on the blood of warm-blooded animals. Mammals infected with heartworms have circulating larvae in the bloodstream. When a mosquito ingests blood from a heartworm infected animal, the larvae mature and develop in the host. The larvae eventually migrate into the heart and pulmonary vessels where they mature and cause clinical signs of heartworm disease.

The clinical signs of heartworm disease in dogs often to do not become evident until late in the course of the disease. These signs include coughing, exercise intolerance, lethargy, collapse, and even sudden death.

Heartworm disease diagnosis in cats can be challenging. The disease in cats tends to cause signs that mimic asthma. Coughing is the predominant sign, but vomiting and acute sudden unexplained death has been reported. There is no treatment for heartworm disease in cats because cats go into anaphylactic shock when the worms die. The object of heartworm treatment is to kill the heartworms which could induce anaphylaxis. The drugs that are used to treat heartworm disease are also toxic in cats.

Heartworm disease is preventable in all the affected species. The heartworm prevention comes in many forms including : chewable monthly tablets, monthly topical applications that have flea prevention included, and now a 6 month shot for dogs.

Heartworm treatment is expensive. Heartworm prevention is inexpensive and safe. Heartworm disease can cause permanent damage to the pet’s heart. Pets that are not on heartworm prevention, especially in Florida where the mosquito is the state bird, are likely to result in the pet becoming infected with heartworms. I tell clients it’s the proverbial, “ You can pay me now or you can pay me later!”

There is no reason for an animal to develop heartworm disease. Yearly heartworm blood tests and monthly heartworm prevention will ensure our pets will not contract this potentially deadly disease.

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