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Heartworms Transmission & Prevention

Published by in Heartworms in Pets ·
Tags: canineHeartworm
Canine Heartwor
What is Heartworm disease?
Heartworm disease is caused by a parasite known as Dirofilaria immitis and primarily occurs in canines, but can occur in other animals, like felines. As the namesake alludes to, this parasitic invasion lives most commonly in the right side of the heart, and also the adjacent blood vessels. Their presence in the chambers and blood vessels damages heart function, reduces lung capacity, and in severe cases can be life threatening.
How is heartworm transmitted?
Heartworm is transferred from infected mosquitoes. When a mosquito draws blood from an infected animal, it then subsequently consumes microscopic, immature forms of the parasite. From there, when a mosquito bites a new victim, it then transfers the microscopic forms of the parasite into the animal. In a matter of months the microscopic, immature life forms of the parasite will develop into adults.
The parasitic larvae will take approximately six to seven months to migrate to the animal's heart. From there, once they have reach maturity, they will begin reproducing inside the circulatory system. The parasitic invasion will often occupy the right side of the heart and also the arteries that supply the lungs. This is why, in advance cases, an infected animal will exhibit a chronic cough, and reduced exercise tolerance.  Once symptoms are occurring, this is an indication that the disease is advanced, and becomes challenging to treat. Animals can be infected for quite some time before displaying symptoms. Since heartworm disease can go unnoticed for long periods of time, and can cause severe distress for our pets when untreated, it is best to utilize prevention medications to avoid the parasitic infection. Furthermore, heartworm is a prevalent concern, and according to the American Heartworm Society, heartworm is increasing throughout the world. In areas that have larger populations of wild or stray animals the risk is even higher. Knowing this, prevention is crucial to keeping your pet healthy and safe.
There is treatment available should your pet become infected with heartworm, but there can be associative health risks and it can be costly.
Heartworm protection is available in topical and oral forms, and have been shown to be highly effective.

How can I protect my pet from heartworm disease?
Heartworm protection is available from your veterinarian. Typically, prior to starting heartworm prevention a blood test is highly recommended to ensure your pet is not infected. This is because the immature forms of heartworm are susceptible to the preventative medication and will likely die abruptly in the bloodstream which can cause anaphylaxis. This anaphylactic reaction can be fatal. Furthermore, the preventative medication cannot kill adult heartworms, so if there are adult heartworms in your pet, they will remain untreated and continue to damage the cardiovascular and respiratory system of your furry loved one. Book an appointment with our veterinarian in newmarket at Brooker Ridge Animal Hospital to discuss the options to protect your dog from heartworms.

Canine Heartworm

Published by in Heartworms in Pets ·
Tags: HeartwormParasite
Dog Heartworm:
Heartworm (Dirofilaria immitis) is a large worm - the adult worm can be up to 14 inches long lives in the right side of the heart and pulmonary arteries of an infected dog. Dogs acquire heartworm infection through bites from infected mosquito with heartworm larva.
Canine Heartworm

In the pulmonary arteries of an infected dog, the worm generates an inflammatory response. Presence of a lot of worms reduces the capacity of the heart and this heart must work extra hard to compensate the deficit.

Microfilariae (First Stage Larvae). female worms after mating with adult male in the infected heart they begin laying directly baby worms (larva) that called microfilariae. Microfilariae are released into the circulatory system waiting to be slurped up by a mosquito taking a blood meal and carried to a new host which is usually a domestic dog, coyote, or fox (although a wide variety of other animals can also be infected such as cats and ferrets, in rare instances humans). Microfilariae may live up to two years within the host dog, they die of old age after this period, if a mosquito has not picked them up. Microfilariae may also be transmitted across the placental barrier to puppies from infected mother.

Heartworm preventive Medication such as Ivermectin, selamectin, and milbemycin based will kill microfilariae (fisrt stage larvae), but they have little effect (L5, young adult heartworms) or no effect against Dirofilaria immitis (adult heartworms).

Inside the infected Mosquito:
The microfilariae will take few weeks to develop to L2s and finally to L3s, the stage capable of infecting a new dog usually through the dog nose which is vulnerable to mosquito bites.

Inside the infected Dog:
When a dog is bitten by an infected mosquito, the L3 is not deposited directly into the bloodstream will develop to L4 in 1-2 weeks that lives in the skin until develops to the L5 stage (young adult) that migrates to the heart and pulmonary arteries, where it will mate approximately five to seven months after first entering the infected host. This is why there is no point in testing puppies less than five months of age for adult heartworm antigen.

Heartworm disease Signs:
A mild persistent cough, decreased appetite, exercise intolerance, fatigue after moderate activity, and weight loss. If you notice one or more of these symptoms contact your veterinarian or call our veterinary clinic in Newmarket Aurora area at 905-898-1010 even your pet is dewormed. Deworming usually does not include medicine that can be effective against Heartworm. Read more on Heartworm in Dogs and Cats

Brooker Ridge Animal Hospital - 107-525 Brooker Ridge, Newmarket, ON - T: 905-898-1010
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