Video: "Heartworm Disease" (3:00)—Dr. Scribano talks about how pets get heartworms, their effects, and how we can help prevent them.
Featured Quote - "The oral once a month prevention methods are good, but they're only good if you give it every single month and most of us are human, not superhuman."
Heartworms are parasites that can grow to be one foot long and live inside the heart, arteries, and lungs. While heartworms find dogs to be the more hospitable host, they can also live inside cats, mainly during the younger stages of the heartworm life cycle. Most heartworms in cats do not survive into adulthood, and infected cats typically have fewer than six worms. However, even one or two immature worms can make a cat very sick.
The culprit in heartworm spread and infection is the mosquito. Heartworm larvae in an infected cat circulate through the bloodstream. A mosquito bites an infected animal and ingests its blood, along with the heartworm larvae. The mosquito then bites a healthy cat, and the larvae make their way into the cat's bloodstream through the wound.
Symptoms of cat heartworm disease are much like symptoms of other illnesses, or cats may show no symptoms at all before they collapse and die from heartworm infection. If symptoms do appear, coughing and rapid breathing are common. Cats may also suffer loss of appetite, weight loss, and vomiting.
Heartworms can cause severe organ damage that leads to heart failure and lung disease. In cats, heartworm disease more often involves the lungs. Smaller, immature worms can enter the lungs and cause Heartworm Associated Respiratory Disease, which is severe lung damage.
Both outdoor and indoor cats are susceptible to heartworm disease, since mosquitoes proliferate outside and can enter the home. About 33% of all infected cats are indoor cats. Unfortunately, there is no approved medication that kills adult heartworms in cats. Current medications to remove heartworms are not suitable for felines, and heartworm preventatives only target worms that are still in the larval stages.
Further, immature heartworms can cause death if cat heartworm prevention is not administered under the care of a veterinarian. This is because young worms in the bloodstream can suddenly die from the medication and trigger heart failure, respiratory failure, and other complications. So never start your cat on heartworm prevention without a complete feline exam by your veterinarian.
Early detection and full protection are the only ways to keep cats free of heartworm disease. Heartworm prevention should be provided for your cat, along with regular heartworm tests by your pet’s doctor, to ensure any current or future infections are kept at bay. Talk to your veterinarian about the best testing and prevention schedule for your cat.