Heartworms (Dirofilaria immitis) are serious and potentially fataldisease-causing parasites of both dogs and cats. Adult worms present within the heart can cause problems in dogs and cats often have worms that invade their lungs. But how do they get there??? These parasites are transmitted by mosquitos!

The lifecycle of heartworms begins with the adult female releasing young called microfilariae into the bloodstream of a dog (or cat). Mosquitos feeding on this animal become infected with the microfilariae and the parasites mature into infective larva inside the mosquito. This process takes 10-14 days but after that, when the mosquito bites another dog (or cat) the infective larvae enter through the bite wound. Approximately 6 months later, the larvae have matured into adult worms, reproducing and starting the cycle over again.

Heartworms – Dirofilaria immitis

Fortunately, they are relatively easy to prevent, given the appropriate prophylactic treatment. Awareness of the problem is the first step! Make sure your pets are on a scheduled heartworm preventative but always have your veterinarian do a heartworm test before beginning any preventative protocol.