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Parasitologist On Double Defense to Prevent Heartworm in Dogs


Veterinary parasitologist Dr. Michael Dryden explains how heartworm in dogs occurs HERE Steve Dale’s Pet World national radio show.

Dr. Michael Dryden

Heartworm is delivered to dogs by various species of mosquitoes who bite, and deliver a microfilaria, which is the early stage of heartworm. The “baby heartworm” makes it’s way through a dog’s blood stream to the pulmonary system of the pet and lands there to grow. Over time, they grow into about spaghetti length adult heartworm. One unprotected dog can have a load of a few heartworm, dozens of heartworm or even hundreds. No wonder this can sicken or kill dogs, and definitely impacts quality of life.

Dryden explains, there’s now documentation that some heartworm (the worms themselves) appears to be resistant to the monthly preventives (no matter what monthly product you use). The products are otherwise about perfect, unless you happen come across resistant heartworm. Also, sometimes people forget to give the heartworm preventive – when that happens, obviously the product can’t do what it’s supposed to.

Who wants to see this in their dog?

The Centers for Disease Control suggests that to protect people from mosquito transmitted diseases, like malaria, using a multi-modal approach, a double protection or double defense.

Dryden, who is a professor at Kansas State University College of Veterinary Medicine, notes that this same approach is now being suggested by some in veterinary medicine, using Vectra 3D in conjunction with a traditional heartworm preventive. Vectra 3D repels the mosquitoes and also protects against fleas and ticks (which is necessary anyway). Use the double defense method and your pup WILL be protected against heartworm.


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