Can Heartworm in Cats Be Contagious?

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Written By
Tom Ryan
Tom Ryan
Oct 23, 2012
2 minute read

Heartworm is a contagious parasite that can spread between cats, but only with the aid of mosquitoes that transmit the bug from host to host. While you can't get heartworm from your kitty, other cats or your dog can, and vice versa, so prevention is key.

How Heartworm Spreads

Heartworm lives inside the body, and it doesn't move from host to host like a flea or a louse. Instead, a mosquito has to bite the infected host, then fly to another animal and bite it, transmitting the parasite from one host to another. Of course, the mosquito does this unknowingly -- he's just looking to suck some blood. In the end, though, it is the mosquito's actions that spread heartworm, making outdoor cats especially susceptible to contracting the parasite.

Signs of Heartworm

If you suspect that your cat has heartworm, take her to a vet who can assess the seriousness of her condition. Infected cats most often show respiratory problems, like difficulty breathing and severe coughing, but can also lose their appetite and consequently lose weight. An infected cat may be lethargic, listless and prone to vomiting, as well.

Fighting Heartworm

While there are no medical courses of action that specifically treat feline heartworm, many cats are able to battle the parasite on their own. As for the rest, your vet may be able to treat the symptoms of heartworm, if not the parasite itself. For example, your vet may give Fluffy medication to improve her lung function, which may have been affected by the parasite.

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Heartworm Prevention

Since both indoor and outdoor cats are at risk for this contagious and incurable parasite, administer a preventative medication. After assessing your cat's health and risk, your vet can recommend a preventative heartworm medication. These medications are typically taken once a month, and effectively eliminate the risk of contracting the parasite.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

Tom Ryan

Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public…

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