Heartworm, a life-threatening parasitic infection, sickens dogs, cats, and ferrets in all 50 states. Like many diseases, heartworm is much easier to prevent than treat. National Heartworm Awareness Month, held every April, offers a timely reminder of the devastating health effects of heartworm disease.
How Do Pets Get the Disease?
Heartworm disease is transmitted when a mosquito bites an infected animal and then bites your pet. Heartworm larvae are circulated through your pet's body via the bloodstream and eventually become immature or mature worms.
After traveling through your dog's body for months, the larvae begin to grow into long, white worms that look like cooked spaghetti. Those that reach the blood vessels of the heart and lungs cause the most damage.
Male heartworms measure 4 to 6 inches in length, while females may be as long as 10 to 12 inches, according to the U.S. Food & Drug Administration (FDA). The FDA notes that dogs can be infected with one to 250 worms. Each worm can live 5 to 7 years.
Cats are more likely to be infected with immature worms, although some cats do have a few mature worms. Even immature worms can affect your cat's health, causing serious breathing difficulties.
In ferrets, one or two heartworms settle in the pulmonary artery in the heart. As the worms grow, the heart becomes dangerously enlarged.
What Are the Symptoms of Heartworm Disease?
Symptoms don't usually occur during the early stages of infection. As the worms grow, your dog may start to cough, seem abnormally tired after mild to moderate exercise, eat less, lose weight and have trouble breathing. Eventually, the infection can cause a swollen abdomen, abnormal lung sounds, collapse or death.
Cats infected with heartworms may develop heartworm associated respiratory disease (HARD). When immature worms reach the small arteries in the lungs, an inflammatory response occurs that damages the air sacs, arteries, and small airways, according to the Cornell University of Veterinary Medicine.
An infected cat may have difficulty breathing or breathe rapidly. Other signs and symptoms include a disinterest in food, weight loss, vomiting, diarrhea, coughing, gagging, collapse or death.
Symptoms in ferrets also include loss of appetite and weight loss, in addition to coughing, shortness of breath, vomiting, swelling in the abdomen or chest, heart murmur and fatigue. If heart damage is severe, ferrets may suddenly collapse and die.
How Is Heartworm Disease Treated?
Treatment varies depending on the animal. Dogs receive medications that kill mature and immature heartworms and reduce inflammation. The treatment can take a toll on your pet's body, particularly if your dog's health is already fragile due to the infection. In some cases, surgery may be needed to remove the worms. Even if heartworm surgery is successful, the damage to your dog's heart, lungs, and organs will be permanent.
Medications that kill heartworms aren't safe for use in cats. Instead, your pet may receive drugs that will reduce inflammation, antibiotics, cardiovascular medication or oxygen therapy if breathing becomes difficult. In severe cases, surgery may also be recommended to remove the worms.
Many of the medications and treatment strategies used to treat heartworm infections in cats can also be used for ferrets. Unfortunately, medications that kill heartworms will also kill your ferret.
How Can Heartworm Disease Be Prevented?
Oral, topical, and injectable heartworm medications reduce your pet's heartworm risk. Your veterinarian can help you decide which type of medication is best for your pet. Oral and topical medications must be given or applied every month, while injectable medication protects your pet for six months.
It's best to give your pet heartworm medication year-round, even if you live in a cold climate, as mosquito season may not always follow the same pattern every year. Providing constant protection ensures that your furry friend will never have to face this debilitating disease.
Does your pet need a prescription for heartworm medication? Contact our office to schedule a convenient appointment.