Heartworm disease is a serious and potentially fatal disease in pets that is on the rise in Vermont. It is caused by heartworms that live in the heart, lungs and associated blood vessels of affected pets. This can lead to severe lung disease, heart failure and damage to other organs in the body. Heartworm disease affects dogs, cats and ferrets. Heartworms are transmitted when an infected mosquito bites the pet.
The dog is a natural host for heartworms so they can live inside the dog and mature into adults, mate and produce offspring. If untreated, their numbers increase, and cause lasting damage to the heart, lungs and arteries, which can affect the dog’s health and quality of life even after the parasites are gone. For this reason, prevention is by far the best option, and treatment should be administered as early in the course of the disease as possible.
Heartworm disease in cats is very different from heartworm disease in dogs since cats are atypical hosts for heartworms: most worms in cats do not survive to the adult stage. Cats with adult heartworms typically have just one to three worms, which causes heartworm disease to go undiagnosed in cats. Immature worms cause a condition known as heartworm associated respiratory disease, which causes coughing, difficulty breathing, and potential death. Since the medication used to treat heartworm infections in dogs cannot be used in cats, prevention is the only means of protecting cats from heartworm disease.
In the early stages of the disease, many pets show few symptoms or no symptoms at all. The longer the infection persists, the more likely symptoms will develop in dogs. Some cats will never show symptoms. Active dogs, dogs heavily infected with heartworms, or those with other health problems often show pronounced clinical signs.
The classic signs of heartworm disease include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss. As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen.
Heartworm disease has been diagnosed in all 50 states, and risk factors are impossible to predict. Infected mosquitoes can come inside so outdoor and indoor pets are at risk: the American Heartworm Society recommends that you get your pet tested every 12 months for heartworm and give your pet heartworm preventive year-round. Treatment for heartworm disease is only possible in dogs, as cats cannot tolerate the medication used, and is both costly and has serious risks associated with it. Heartworm prevention is a prescription product and is available for dogs and cats. Ask your veterinary office for more information today.
Erin Forbes, DVM is a member of the Vermont Veterinary Medical Association (VVMA), founded in 1898, as a professional organization of 370 veterinarians dedicated to compassionate animal care and quality medicine.