How do cats get heartworm? The same way dogs do: through the bite of an infected mosquito. Studies show cats are infected with juvenile worms at a rate similar to that of dogs.1 However, the resulting disease is drastically different.
It’s a cat thing: the disease
Heartworms in cats are typically smaller than they are in dogs. Heartworm‐positive dogs can be infected with multiple worms at once, whereas cats are typically only infected with one or two.
While heartworms can live and grow quite happily in a dog for up to seven years, they can usually only live for two to four years in a cat. This is because heartworms in cats trigger an intense immune reaction that does not take place in dogs. It is this amped‐up immune response that causes trouble for cats.
Heartworm symptoms in cats are usually associated with the airways and include coughing, rapid chest movements and difficulty breathing. In fact, a cat with heartworms can easily resemble a cat with asthma. However, it is not uncommon for cats to experience sudden death without ever showing signs at all.
Heartworm Associated Respiratory Disease
Heartworm Associated Respiratory Disease is a condition that cats most often experience with heartworms, which causes them to cough, wheeze, and generally have difficulty breathing. It can cause vomiting and weight loss and is easily confused with feline asthma.
Testing and treatment
A veterinarian can test your cat for heartworms, but they might be expensive tests and hard on your cat. Even with testing, worms in cats can be difficult to diagnose and, unfortunately, there is no approved treatment for heartworms in cats.
Heartworm prevention for cats
Because there’s no treatment for cats that test positive, veterinarians recommend preventing heartworm disease in the first place. Where there are mosquitoes, there can be heartworm disease. You cannot ensure a mosquito‐free environment any time of year, especially in warm, humid areas of the country.
Thankfully, there are safe and effective ways to prevent heartworm disease.
Bayer’s Advantage Multi® for Cats (imidacloprid + moxidection) is a topical prescription product that prevents heartworm disease. It also treats and controls ear mites, hookworms and roundworms and kills fleas — all in one convenient monthly treatment. Ask your veterinarian how to get a prescription for your cat.
CAUTION: Federal (U.S.A.) law restricts Advantage Multi® for Cats (imidacloprid + moxidectin) to use by or on the order of a licensed veterinarian. WARNINGS: Do not use on sick or debilitated cats or ferrets. Do not use on cats less than 9 weeks of age or less than 2 lbs body weight. HUMAN WARNINGS: Children should not come in contact with the application site for 30 minutes after application.
See the Advantage Multi® for Cats Product Label.
1. Feline heartworm. Current advice on parasite control: heartworm – feline heartworm. Companion Animal Parasite Council website. Available at: http://www.capcvet.org/capc‐ recommendations/feline‐heartworm. Accessed June 5, 2015.
Related article: Understand the flea life cycle