What causes dog heartworm?

It is a parasite that is transmitted through a mosquito. The mosquito will have the larval or the microfilaria stage. As the mosquito bites your pet, it delivers that microfilaria into your pet, and then from there, that microfilaria develops and grows into the adult heartworm.

Dog heartworm is caused by a parasite that lives in their blood and migrates to their heart.

Dog heartworms are spread by mosquitoes. Here in this area, we've seen mosquitoes 12 months out of the year. We don't have a cold enough winter to eradicate those mosquitoes. A mosquito that is infected with heartworms bites your dog and spreads those little microfilariae or those baby heartworms into your dog's bloodstream, where they then go and set up shop in the lung and heart area. They reproduce and multiply and cause problems with your dog.

Heartworms in dogs are caused by foot-long worms that primarily live in the heart, lungs, and major blood vessels. These worms can cause heart failure, lung disease, or other serious health issues in dogs.

Canine heartworm disease is caused by heartworms, which are parasites that live in the bloodstream.