Dogs get heartworm disease through the bite of an infected mosquito. The process involves several steps:
- Adult female heartworms living in an infected dog produce microscopic baby worms called microfilariae that circulate in the dog's bloodstream.
- When a mosquito bites this infected dog, it ingests these microfilariae.
- Inside the mosquito, the microfilariae develop into infective larvae over 10 to 14 days.
- When the infected mosquito bites another dog, it deposits these infective larvae onto the dog's skin, and they enter the dog's body through the mosquito bite wound.
- The larvae then migrate into the dog's bloodstream and eventually reach the heart and lungs, where they mature into adult heartworms over about 6 to 7 months.
- Adult heartworms live in the heart and pulmonary arteries, where they can cause serious damage and reproduce, continuing the cycle
Heartworm disease is not contagious directly between dogs; it requires the mosquito as an intermediate host for transmission
