Heartworms in cats
Heartworms in cats: is a potentially fatal disease that any cat can get in a geographic area where mosquitoes breed. Heartworm may show no serious outward signs in a cat, or the signs can seem like many other feline illnesses—but it can be devastating.
It’s unclear why vets do not usually educate people about this risk to cats, who need every bit of protection they can get from it, even cats who stay mostly indoors. Please go to the American Heartworm Society for more information.
- Please note that heartworm is a vastly under treated illness in cats.
- In whatever areas dogs are being protected from heartworm, cats should also be on a preventive medication, especially if you live in an area where mosquitoes breed.
- Heartworm tests for cats are not reliable, so you need to evaluate your cat’s need for protection with your vet based on the prevalence of mosquitoes where you live.
- Illness is less likely in the Northeast than in the southeastern states, where it is best to consistently keep your cat on heartworm medication.
The Disease Itself.
- Dogs are the hosts for heartworm disease, and can have immature heartworm larvae circulating in their blood.
- The illness is spread to other animals when a mosquito draws blood from an infected dog and the insect takes in the microscopic larvae with that blood meal.
- Over 2 to 3 weeks the larvae develop inside the mosquito; when they reach the infectious stage and the mosquito feeds again on another dog or on a cat, the insect transmits the infectious larvae into the bloodstream of the new host.
- It takes months for the worms to develop, traveling through the animal’s body until they reach the right side of the heart and the arteries of the lungs. In cats, the main location where heartworms grow is in the lungs, despite the name of the parasite.
Cats have natural resistance to heartworms, but they can still become infected.There is a higher risk of infection in areas where there are more mosquitoes carrying heartworm larvae.
With no exposure to infected mosquitoes, cats cannot get heartworm. Preventive medication is available to protect cats who are at risk for heartworms in cats. Ask your veterinarian about the risk of heartworm in your area, and then decide if preventive care is needed.
Heartworms symptoms in cats
Because heartworms in cats can take years to develop, and blood tests on cats are inconclusive about whether the worms are in their bodies, testing becomes pointless.
Years ago, it was thought to be dangerous to give preventive medication against heartworm to animals already infected. However, that is no longer a worry. Since there is no way to know through outward signs or from a blood test whether a cat has been infected, it is recommended to protect all cats with preventive medication.
Diagnosis of the heartworms in cats
Heartworms in cats should be considered as a possible diagnosis for cats who have signs of :
- heart disease
- Fluid in the lungs
- Sudden Death
- vomiting or asthma
- Difficult or labored breathing
- Anorexia/Weight Loss
- live in a high-risk area where mosquitoes are present.
Blood tests that look for antigens to the parasite and antibodies the cat produces against the parasite are useful in making a diagnosis. Heartworms in cats can be observed on an ultra- sound of the heart.
Prevention and Medications for Heartworms in cats.
Feline practitioners are alarmed because unlike dogs, 65 percent of whom are given medication, fewer than 5 percent of all cats are on heartworm prevention.
Since there is no way to be certain that a cat has not been infected, and there is no effective treatment, the only way to keep a cat safe is to have her on preventive care.
Think of it as polio in people—preventive medication was the only option. There are three equally effective medications available that need to be used every month, year round.
- Heartgard for Cats (ivermectin) is a chewable tablet
- while topical solutions to put on the skin monthly are Revolution (selemectin) and Interceptor (milbemycin oxine).
Sudden death can occur in cats infected with heartworms due to embolization.This is because clots (emboli) caused by the worms can lodge in the heart, brain or lungs and block blood flow.
There are potential complications regardless of the treatment used. The toxicity and side effects of treatments that kill adult heart- worms (adulticides) in cats are considered more of a risk than living with the parasites for cats who have mild clinical signs.
Depending on their location in the heart, worms can sometimes be removed with special forceps or brushes. Adult worms usually only live for about two years in cats, so if the clinical signs they are creating can be controlled medically, adulticides are not used. Conservative medical treatment consists of using cortisone to control the inflammation caused by the worms in the airways.
Increased Risk of Heartworms in cats When Traveling.
Because so many people choose to travel with their dogs and cats, the incidence of heartworm is spreading, and the illness can now be found across most of the United States.
Many dogs and cats have immature heartworm larvae in their blood, unbeknown st to anyone. All it takes is for a mosquito to bite them, and then for them to contaminate local pets, who can then in turn pass on the heartworm to pets in other areas as soon as a mosquito there transmits the disease.
Texas has a much greater number of heartworm cases than any other state in the country. In a study conducted by the American Heartworm Society, Texas had nearly twice as many cases as the next most infected state, Florida, followed by Louisiana, North Carolina, Georgia, Mississippi, Tennessee, South Carolina, Alabama, Indiana, Arkansas, Missouri, Illinois and Michigan.
But when you take into consideration how many people on the East Coast spend winters in Florida with their pets and then bring them back up north, you can see how easily the disease can spread across state lines. The only responsible way to keep your cat and others from becoming infected is to keep her on heartworm medication year round.
West Nile Virus
- The only way West Nile virus can be transmitted is when mosquitoes feed on birds that are carrying the virus and then pass the disease to humans and other animals by biting them.
- The virus cannot be transmitted directly between animals, or from animals to people. Wild birds and horses are the only animals identified as carriers of the virus; the risk to pets is very low.
- The best way to prevent West Nile is to reduce the chance of your cat being bitten by mosquitoes.
Reducing Your Cat’s Exposure To Mosquitoes
- Keep pets indoors during early morning and evening hours, when mosquitoes are most actively flying around, if you live in an area where mosquitoes are prevalent.
- Consult with your vet before applying any repellent to your cat because it is considered unwise. There are pyrethrin-based flea sprays with directions for use in cats, but many vets do not advocate using them.
- Do not use mosquito products intended for people. Many insect repellents designed for human use contain a chemical that can cause serious illness in cats.
- Do not use any product containing DEET, which research has shown to cause serious adverse effects in pets.
- Avoid citrus oil extracts (citronella) and essential oils; some cats are sensitive to these products.
- If pesticides are sprayed in your area, keep your cat(s) indoors with the windows shut tight during spraying and for several hours afterward.
Read more about cat and kitten behavior:
- Cat vocalizations
- My Kitten is crazy – Crazy kitten behavior
- Using Comfort Zone Feliway
- Cat Marking Territory
- Cat Spraying
- Cat Body Language
- Understand your cat body language and cat behavior
- Cat Separation Anxiety
- Cat Scratching
- Aggression in cats towards others
- Aggressive cat behavior toward other cats and solutions
- Common Cat Behavior Problems and Solutions